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Summary of Content
Vauxhall/Opel Omega Service and Repair Manual Mark Coombs and Spencer Drayton Models covered (3510 - 352) Vauxhall Omega Saloon and Estate models with petrol engines, including special/limited editions 1998 cc, 2498 cc & 2969 cc petrol engines Does not cover diesel engine or bi-fuel (LPG) models ABCDE FGHIJ KLMNO PQRST 123 © Haynes Publishing 1999 A book in the Haynes Service and Repair Manual Series All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage or retrieval system, without permission in writing from the copyright holder. Printed by J H Haynes & Co. Ltd, Sparkford, Nr Yeovil, Somerset BA22 7JJ Haynes Publishing Sparkford, Nr Yeovil, Somerset BA22 7JJ, England Haynes North America, Inc 861 Lawrence Drive, Newbury Park, California 91320, USA ISBN 1 850960 510 9 Editions Haynes S.A. Tour Aurore - La Défense 2, 18 Place des Reflets, 92975 PARIS LA DEFENSE Cedex France British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library. Haynes Publishing Nordiska AB Box 1504, 751 45 UPPSALA, Sverige 3510 Vauxhall/Opel Omega Contents LIVING WITH YOUR VAUXHALL OMEGA Introduction Page 0•4 Safety First! Page 0•5 Introduction Page 0•6 If your car won’t start Page 0•6 Jump starting Page 0•7 Wheel changing Page 0•8 Identifying leaks Page 0•9 Towing Page 0•9 Roadside Repairs Weekly Checks Introduction Page 0•10 Underbonnet check points Page 0•10 Engine oil level Page 0•11 Coolant level Page 0•11 Brake (and clutch) fluid level Page 0•12 Power steering fluid level Page 0•12 Battery Page 0•13 Electrical systems Page 0•13 Tyre condition and pressure Page 0•14 Tyre tread wear patterns Page 0•14 Washer fluid level Page 0•15 Wiper blades Page 0•15 Lubricants and fluids Page 0•16 Tyre pressures Page 0•17 MAINTENANCE Routine Maintenance and Servicing Servicing specifications Page 1•2 Maintenance schedule Page 1•3 Maintenance procedures Page 1•6 3510 Vauxhall/Opel Omega Contents REPAIRS & OVERHAUL Engine and Associated Systems 2.0 litre SOHC engine in-car repair procedures Page 2A•1 2.0 litre DOHC engine in-car repair procedures Page 2B•1 2.5 and 3.0 litre engine in-car repair procedures Page 2C•1 General engine overhaul procedures Page 2D•1 Cooling, heating and ventilation systems Page Fuel and exhaust systems Page 4A•1 Emission control systems Page 4B•1 Starting and charging systems Page 5A•1 Ignition system Page 5B•1 3•1 Transmission Clutch Page Manual transmission Page 7A•1 6•1 Automatic transmission Page 7B•1 Final drive, driveshafts and propeller shaft Page 8•1 Braking system Page 9•1 Suspension and steering Page 10•1 Brakes and Suspension Body equipment Bodywork and fittings Page 11•1 Body electrical system Page 12•1 Wiring Diagrams Page 12•23 REFERENCE Dimensions and weights Page REF•1 Conversion Factors Page REF•2 Buying Spare Parts and Vehicle Identification Page REF•3 General Repair Procedures Page REF•4 Jacking and vehicle support Page REF•5 Radio/cassette unit anti-theft system precaution Page REF•5 Tools and working facilities Page REF•6 MOT Test Checks Page REF•8 Fault Finding Page REF•12 Glossary of Technical Terms Page REF•20 Index Page REF•24 3510 Vauxhall/Opel Omega 0•4 Introduction The Vauxhall Omega was introduced into the UK in April of 1994 as a replacement for the Vauxhall Carlton and Senator. At its launch, the Omega was available in both Saloon and Estate body styles with a choice of either 2.0 litre (1998 cc) or a 2.5 litre (2498 cc) petrol engine both available with either a 5-speed manual transmission unit or a 4speed automatic transmission unit. Shortly afterwards a 3.0 (2968 cc) litre petrol engine was also introduced. A 2.5 litre Diesel engine (not covered in this manual) was also available. The petrol engines are all well-proven units which are used in many other Vauxhall vehicles; the engine is mounted at the front of vehicle with the transmission mounted on its rear. Two versions of the four-cylinder 2.0 litre engine were used; low specification vehicles were fitted with a single overhead camshaft (SOHC) 8-valve engine were as all other vehicles were fitted with the double overhead camshaft (DOHC) 16-valve engine often referred to as the ECOTEC engine. The 2.5 and 3.0 litre engines are both V6, double overhead camshaft (DOHC) units which are also often referred as ECOTEC engines. All models have fully-independent front and rear suspension and are equipped with front and rear disc brakes. A wide range of standard and optional equipment is available within the range to suit most tastes, including central locking, electric windows and an electric sunroof. An air conditioning system was available as an option on certain models. Provided that regular servicing is carried out in accordance with the manufacturer’s recommendations, the vehicle should prove reliable and very economical. The engine compartment is well-designed, and most of the items requiring frequent attention are easily accessible. Vauxhall Omega 2.0 16V Select Vauxhall Omega Estate CD The Vauxhall Omega Team Haynes manuals are produced by dedicated and enthusiastic people working in close co-operation. The team responsible for the creation of this book included: Authors Sub-editor Editor & Page Make-up Workshop manager Photo Scans Cover illustration & Line Art Wiring diagrams Marc Coombs Spencer Drayton Ian Barnes Steve Churchill Paul Buckland Steve Tanswell John Martin Roger Healing Matthew Marke We hope the book will help you to get the maximum enjoyment from your car. By carrying out routine maintenance as described you will ensure your car’s reliability and preserve its resale value. Your Vauxhall Omega manual The aim of this manual is to help you get the best value from your vehicle. It can do so in several ways. It can help you decide what work must be done (even should you choose to get it done by a garage). It will also provide information on routine maintenance and servicing, and give a logical course of action and diagnosis when random faults occur. However, it is hoped that you will use the manual by tackling the work yourself. On simpler jobs it may even be quicker than booking the car into a garage and going there twice, to leave and collect it. Perhaps most important, a lot of money can be saved by avoiding the costs a garage must charge to cover its labour and overheads. The manual has drawings and descriptions to show the function of the various components so that their layout can be understood. Tasks are described and photographed in a clear step-by-step sequence. References to the ‘left’ and ‘right’ are in the sense of a person in the driver’s seat, facing forwards. Acknowledgements Thanks are due to Champion Spark Plug, who supplied the illustrations showing spark plug conditions. Certain illustrations are the copyright of Vauxhall Motors Limited, and are used with their permission. Thanks are also due to Draper Tools Limited, who provided some of the workshop tools, and to all those people at Sparkford who helped in the production of this manual. We take great pride in the accuracy of information given in this manual, but vehicle manufacturers make alterations and design changes during the production run of a particular vehicle of which they do not inform us. No liability can be accepted by the authors or publishers for loss, damage or injury caused by any errors in, or omissions from, the information given. 3510 Vauxhall/Opel Omega Safety first! Working on your car can be dangerous. This page shows just some of the potential risks and hazards, with the aim of creating a safety-conscious attitude. General hazards Scalding • Don’t remove the radiator or expansion tank cap while the engine is hot. • Engine oil, automatic transmission fluid or power steering fluid may also be dangerously hot if the engine has recently been running. Burning • Beware of burns from the exhaust system and from any part of the engine. Brake discs and drums can also be extremely hot immediately after use. Crushing • When working under or near a raised vehicle, always supplement the jack with axle stands, or use drive-on ramps. Never venture under a car which is only supported by a jack. • Take care if loosening or tightening hightorque nuts when the vehicle is on stands. Initial loosening and final tightening should be done with the wheels on the ground. • Mains voltage is also dangerous. Make sure that any mains-operated equipment is correctly earthed. Mains power points should be protected by a residual current device (RCD) circuit breaker. Fume or gas intoxication • Exhaust fumes are poisonous; they often contain carbon monoxide, which is rapidly fatal if inhaled. Never run the engine in a confined space such as a garage with the doors shut. • Fuel vapour is also poisonous, as are the vapours from some cleaning solvents and paint thinners. Poisonous or irritant substances • Avoid skin contact with battery acid and with any fuel, fluid or lubricant, especially antifreeze, brake hydraulic fluid and Diesel fuel. Don’t syphon them by mouth. If such a substance is swallowed or gets into the eyes, seek medical advice. • Prolonged contact with used engine oil can cause skin cancer. Wear gloves or use a barrier cream if necessary. Change out of oilsoaked clothes and do not keep oily rags in your pocket. • Air conditioning refrigerant forms a poisonous gas if exposed to a naked flame (including a cigarette). It can also cause skin burns on contact. Fire Asbestos • Fuel is highly flammable; fuel vapour is explosive. • Don’t let fuel spill onto a hot engine. • Do not smoke or allow naked lights (including pilot lights) anywhere near a vehicle being worked on. Also beware of creating sparks (electrically or by use of tools). • Fuel vapour is heavier than air, so don’t work on the fuel system with the vehicle over an inspection pit. • Another cause of fire is an electrical overload or short-circuit. Take care when repairing or modifying the vehicle wiring. • Keep a fire extinguisher handy, of a type suitable for use on fuel and electrical fires. • Asbestos dust can cause cancer if inhaled or swallowed. Asbestos may be found in gaskets and in brake and clutch linings. When dealing with such components it is safest to assume that they contain asbestos. Electric shock • Ignition HT voltage can be dangerous, especially to people with heart problems or a pacemaker. Don’t work on or near the ignition system with the engine running or the ignition switched on. 0•5 Special hazards Hydrofluoric acid • This extremely corrosive acid is formed when certain types of synthetic rubber, found in some O-rings, oil seals, fuel hoses etc, are exposed to temperatures above 4000C. The rubber changes into a charred or sticky substance containing the acid. Once formed, the acid remains dangerous for years. If it gets onto the skin, it may be necessary to amputate the limb concerned. • When dealing with a vehicle which has suffered a fire, or with components salvaged from such a vehicle, wear protective gloves and discard them after use. The battery • Batteries contain sulphuric acid, which attacks clothing, eyes and skin. Take care when topping-up or carrying the battery. • The hydrogen gas given off by the battery is highly explosive. Never cause a spark or allow a naked light nearby. Be careful when connecting and disconnecting battery chargers or jump leads. Air bags • Air bags can cause injury if they go off accidentally. Take care when removing the steering wheel and/or facia. Special storage instructions may apply. Diesel injection equipment • Diesel injection pumps supply fuel at very high pressure. Take care when working on the fuel injectors and fuel pipes. Warning: Never expose the hands, face or any other part of the body to injector spray; the fuel can penetrate the skin with potentially fatal results. Remember... DO DON’T • Do use eye protection when using power tools, and when working under the vehicle. • Don’t attempt to lift a heavy component which may be beyond your capability – get assistance. • Do wear gloves or use barrier cream to protect your hands when necessary. • Do get someone to check periodically that all is well when working alone on the vehicle. • Do keep loose clothing and long hair well out of the way of moving mechanical parts. • Do remove rings, wristwatch etc, before working on the vehicle – especially the electrical system. • Do ensure that any lifting or jacking equipment has a safe working load rating adequate for the job. 3510 Vauxhall/Opel Omega • Don’t rush to finish a job, or take unverified short cuts. • Don’t use ill-fitting tools which may slip and cause injury. • Don’t leave tools or parts lying around where someone can trip over them. Mop up oil and fuel spills at once. • Don’t allow children or pets to play in or near a vehicle being worked on. 0•6 Roadside repairs The following pages are intended to help in dealing with common roadside emergencies and breakdowns. You will find more detailed fault finding information at the back of the manual, and repair information in the main chapters. If your car won’t start and the starter motor doesn’t turn If your car won’t start even though the starter motor turns as normal M If it’s a model with automatic transmission, make sure the selector is in ‘P’ or ‘N’. M Open the bonnet and make sure that the battery terminals are clean and tight. M Switch on the headlights and try to start the engine. If the headlights go very dim when you’re trying to start, the battery is probably flat. Get out of trouble by jump starting (see next page) using a friend’s car. M Is there fuel in the tank? M Is there moisture on electrical components under the bonnet? Switch off the ignition, then wipe off any obvious dampness with a dry cloth. Spray a water-repellent aerosol product (WD-40 or equivalent) on ignition and fuel system electrical connectors like those shown in the photos. Pay special attention to the ignition coil wiring connector and HT leads. A Check the condition and security of the battery connections B Check that the spark plug HT leads are securely connected by pushing them onto the plugs (where accessible) Check that electrical connections are secure (with the ignition switched off) and spray them with a water dispersant spray like WD40 if you suspect a problem due to damp 3510 Vauxhall/Opel Omega C Check that the spark plug HT leads are securely connected by pushing them onto the DIS module (where accessible) D Check that the engine management system wiring connectors are securely connected Roadside repairs Jump starting will get you out of trouble, but you must correct whatever made the battery go flat in the first place. There are three possibilities: The battery has been drained by repeated attempts to start, or by leaving the lights on. 1 The charging system is not working properly (alternator drivebelt slack or broken, alternator wiring fault or alternator itself faulty). 2 3 1 The battery itself is at fault (electrolyte low, or battery worn out). Connect one end of the red jump lead to the positive (+) terminal of the flat battery 0•7 Jump starting When jump-starting a car using a booster battery, observe the following precautions: 4 Before connecting the booster battery, make sure that the ignition is switched off. 4 Make sure that the booster battery is the same voltage as the discharged one in the vehicle. 4 If the battery is being jump-started from the battery in another vehicle, the two vehicles MUST NOT TOUCH each other. 4 Ensure that all electrical equipment (lights, heater, wipers, etc) is switched off. 4 Take note of any special precautions 4 Make sure that the transmission is in neutral (or PARK, in the case of automatic transmission). printed on the battery case. 2 Connect the other end of the red lead to the positive (+) terminal of the booster battery. 3510 Vauxhall/Opel Omega 3 Connect one end of the black jump lead to the negative (-) terminal of the booster battery 4 Connect the other end of the black jump lead to a bolt or bracket on the engine block, well away from the battery, on the vehicle to be started. 5 Make sure that the jump leads will not come into contact with the fan, drivebelts or other moving parts of the engine. 6 Start the engine using the booster battery and run it at idle speed. Switch on the lights, rear window demister and heater blower motor, then disconnect the jump leads in the reverse order of connection. Turn off the lights etc. 0•8 Roadside repairs Wheel changing Some of the details shown here will vary according to model. Warning: Do not change a wheel in a situation where you risk being hit by another vehicle. On busy roads, try to stop in a lay-by or a gateway. Be wary of passing traffic while changing the wheel - it is easy to become distracted by the job in hand. Preparation M When a puncture occurs, stop as soon as it is safe to do so. M Park on firm level ground, if possible, and well out of the way of other traffic. M Use hazard warning lights if necessary. M If you have one, use a warning triangle to alert other drivers of your presence. M Apply the handbrake and engage first or reverse gear (or Park on models with automatic transmission. M Chock the wheel diagonally opposite the one being removed – a couple of large stones will do for this. M If the ground is soft, use a flat piece of wood to spread the load under the jack. Changing the wheel 1 On Saloon models unclip the luggage compartment left-hand trim panel then release the retaining strap and remove the spare wheel . . . 2 . . . The tools and jack are stored in the smaller compartment on the right-hand side of the luggage compartment. Remove the cover (where fitted) then unscrew the bolt and remove the jack and wheelbrace. 3 4 5 6 . . . then unscrew the retaining bolt and remove the jack from behind the wheel. On models with steel wheels, use the removal tool supplied to pull off the wheel trim and on models with alloy wheels, use the tool supplied to unscrew the anti-theft bolt and remove the hub cap. Slacken each wheel bolt by half a turn. On Estate models lift up the luggage compartment floor panel and remove the tools from the centre of the spare wheel. Undo the retaining nut and remove the spare wheel . . . Unclip the access cover from the sill trim panel then make sure the jack is located on firm ground and engage the jack head correctly with the lifting point on the sill. Make sure that the lug on the jack head is correctly located in the sill seam cutout and the base of the jack is directly underneath the sill seam. Finally... M Remove the wheel chocks. M Stow the punctured wheel, jack and tools in the correct locations in the car. 7 Raise the jack until the wheel is raised clear of the ground. Unscrew the wheel bolts and remove the wheel. Fit the spare wheel and screw on the bolts. Lightly tighten the bolts with the wheelbrace then lower the vehicle to the ground. 8 Securely tighten the wheel bolts in a diagonal sequence then refit the hub cap/wheel trim (as applicable). Note that the wheel bolts should be slackened and retightened to the specified torque at the earliest possible opportunity. 3510 Vauxhall/Opel Omega M Check the tyre pressure on the wheel just fitted. If it is low, or if you don’t have a pressure gauge with you, drive slowly to the nearest garage and inflate the tyre to the right pressure. M Have the damaged tyre or wheel repaired as soon as possible. Roadside repairs 0•9 Identifying leaks Puddles on the garage floor or drive, or obvious wetness under the bonnet or underneath the car, suggest a leak that needs investigating. It can sometimes be difficult to decide where the leak is coming from, especially if the engine bay is very dirty already. Leaking oil or fluid can also be blown rearwards by the passage of air under the car, giving a false impression of where the problem lies. Warning: Most automotive oils and fluids are poisonous. Wash them off skin, and change out of contaminated clothing, without delay. The smell of a fluid leaking from the car may provide a clue to what’s leaking. Some fluids are distictively coloured. It may help to clean the car carefully and to park it over some clean paper overnight as an aid to locating the source of the leak. Remember that some leaks may only occur while the engine is running. Sump oil Oil from filter Gearbox oil Engine oil may leak from the drain plug... ...or from the base of the oil filter. Gearbox oil can leak from the seals at the inboard ends of the driveshafts. Antifreeze Brake fluid Power steering fluid Leaking antifreeze often leaves a crystalline deposit like this. A leak occurring at a wheel is almost certainly brake fluid. Power steering fluid may leak from the pipe connectors on the steering rack. Towing When all else fails, you may find yourself having to get a tow home – or of course you may be helping somebody else. Long-distance recovery should only be done by a garage or breakdown service. For shorter distances, DIY towing using another car is easy enough, but observe the following points: M Use a proper tow-rope – they are not expensive. The vehicle being towed must display an ‘ON TOW’ sign in its rear window. M Always turn the ignition key to the ‘on’ position when the vehicle is being towed, so that the steering lock is released, and that the direction indicator and brake lights will work. M Both front and rear towing eyes are provided. They are located behind the access covers on the front and rear bumper. M Before being towed, release the handbrake and select neutral on the transmission. M Note that greater-than-usual pedal pressure will be required to operate the brakes, since the vacuum servo unit is only operational with the engine running. M On models with power steering, greater- 3510 Vauxhall/Opel Omega than-usual steering effort will also be required. M The driver of the car being towed must keep the tow-rope taut at all times to avoid snatching. M Make sure that both drivers know the route before setting off. M Only drive at moderate speeds and keep the distance towed to a minimum. Drive smoothly and allow plenty of time for slowing down at junctions. M On models with automatic transmission, special precautions apply. If in doubt, do not tow, or transmission damage may result. 0•10 Weekly checks Introduction There are some very simple checks which need only take a few minutes to carry out, but which could save you a lot of inconvenience and expense. M Keeping an eye on tyre condition and pressures, will not only help to stop them wearing out prematurely, but could also save your life. These "Weekly checks" require no great skill or special tools, and the small amount of time they take to perform could prove to be very well spent, for example; M Many breakdowns are caused by electrical problems. Battery-related faults are particularly common, and a quick check on a regular basis will often prevent the majority of these. M If your car develops a brake fluid leak, the first time you might know about it is when your brakes don't work properly. Checking the level regularly will give advance warning of this kind of problem. M If the oil or coolant levels run low, the cost of repairing any engine damage will be far greater than fixing the leak, for example. Underbonnet check points § 2.0 litre DOHC engine A B C D Engine oil level dipstick E F Battery Engine oil filler cap Coolant expansion tank Brake (and clutch) fluid reservoir Power steering fluid reservoir § 2.5 and 3.0 litre engine 3510 Vauxhall/Opel Omega A B C D Engine oil level dipstick E F G Battery Engine oil filler cap Coolant expansion tank Brake (and clutch) fluid reservoir Power steering fluid reservoir Screen washer fluid reservoir Weekly checks 0•11 Engine oil level Before you start 4 Make sure that your car is on level ground. 4 Check the oil level before the car is driven, or at least 5 minutes after the engine has been switched off. If the oil is checked immediately after driving the vehicle, some of the oil will remain in the upper engine components, resulting in an inaccurate reading on the dipstick! The correct oil 1 The dipstick is located on the left-hand side of the engine (see Underbonnet check points on page 0•10 for exact location). Withdraw the dipstick. 2 Using a clean rag or paper towel remove all oil from the dipstick. Insert the clean dipstick into the tube as far as it will go, then withdraw it again. 3 4 Modern engines place great demands on their oil. It is very important that the correct oil for your car is used (See “Lubricants and fluids” on page 0•16). Car Care l If you have to add oil frequently, you should check whether you have any oil leaks. Place some clean paper under the car overnight, and check for stains in the morning. If there are no leaks, the engine may be burning oil (see “Fault Finding”). l Always maintain the level between the upper and lower dipstick marks (see photo 3). If the level is too low severe engine damage may occur. Oil seal failure may result if the engine is overfilled by adding too much oil. Note the oil level on the end of the dipstick, which should be between the upper (MAX) mark and lower (MIN) mark. Approximately 1.0 litre of oil will raise the level from the lower mark to the upper mark. Oil is added through the filler cap. Rotate the cap through a quarter-turn anticlockwise and withdraw it. Top-up the level. A funnel may help to reduce spillage. Add the oil slowly, checking the level on the dipstick often. Do not overfill. Coolant level Warning: DO NOT attempt to remove the expansion tank pressure cap when the engine is hot, as there is a very great risk of scalding. Do not leave open containers of coolant about, as it is poisonous. 1 The coolant level varies with the temperature of the engine. When the engine is cold, the coolant level should be slightly above the KALT/COLD mark on the side of the tank. When the engine is hot, the level will rise. Car Care l With a sealed-type cooling system, adding coolant should not be necessary on a regular basis. If frequent topping-up is required, it is likely there is a leak. Check the radiator, all hoses and joint faces for signs of staining or wetness, and rectify as necessary. 2 If topping up is necessary, wait until the engine is cold. Slowly unscrew the expansion tank cap, to release any pressure present in the cooling system, and remove it. 3510 Vauxhall/Opel Omega l It is important that antifreeze is used in the cooling system all year round, not just during the winter months. Don’t top-up with water alone, as the antifreeze will become too diluted. 3 Add a mixture of water and antifreeze to the expansion tank until the coolant level is slightly above the KALT/COLD mark then securely refit the expansion tank cap. 0•12 Weekly checks Brake and clutch* fluid level *On manual transmission models the brake fluid reservoir also supplies fluid to the clutch master cylinder. Warning: l Brake fluid can harm your eyes and damage painted surfaces, so use extreme caution when handling and pouring it. l Do not use fluid that has been standing open for some time, as it absorbs moisture from the air, which can cause a dangerous loss of braking effectiveness. 1 The upper (MAX) and lower (MIN) fluid level markings are on the side of the reservoir, which is located in the righthand rear corner of the engine compartment. The fluid level must always be kept in between these two marks. • Make sure that your car is on level ground. • The fluid level in the reservoir will drop slightly as the brake pads wear down, but the fluid level must never be allowed to drop below the “MIN” mark. Safety First! l If the reservoir requires repeated toppingup this is an indication of a fluid leak somewhere in the system, which should be investigated immediately. l If a leak is suspected, the car should not be driven until the braking system has been checked. Never take any risks where brakes are concerned. 2 If topping-up is necessary, first wipe clean the area around the filler cap to prevent dirt entering the hydraulic system. 3 Carefully add fluid, taking care not to spill it onto the surrounding components. Use only the specified fluid; mixing different types can cause damage to the system. After topping-up to the correct level, securely refit the cap and wipe off any spilt fluid. Power steering fluid level Before you start: For the check to be accurate, the steering must not be turned once the engine has been stopped. 4 Park the vehicle on level ground. 4 Set the steering wheel straight-ahead. 4 The engine should be turned off. 1 The power steering fluid reservoir is located on the left-hand side of the engine compartment. Wipe clean the reservoir before unscrewing and removing the cap. 2 Wipe clean the filler cap dipstick then refit the filler cap and remove it again. Note the fluid level on the dipstick. 3510 Vauxhall/Opel Omega Safety First! l The need for frequent topping-up indicates a leak, which should be investigated immediately. 3 When the engine is cold the fluid level should be up to the lower mark up the dipstick and when the engine is at operating temperature it should be at the upper mark. Top up the fluid level using the specified type of fluid (do not overfill) then securely refit the filler cap. Weekly checks 0•13 Battery Caution: Before carrying out any work on the vehicle battery, read the precautions given in "Safety first" at the start of this manual. 4 Make sure that the battery tray is in good condition, and that the clamp is tight. Corrosion on the tray, retaining clamp and the battery itself can be removed with a solution of water and baking soda. Thoroughly rinse all cleaned areas with water. Any metal parts damaged by corrosion should be covered with a zinc-based primer, then painted. 4 Periodically (approximately every three months), check the charge condition of the battery as described in Chapter 5A. 4 If the battery is flat, and you need to jump start your vehicle, see Roadside Repairs. Battery corrosion can be kept to a minimum by applying a layer of petroleum jelly to the clamps and terminals after they are reconnected. 1 The battery is located at the front lefthand corner of the engine compartment. If necessary, unclip the fusible link housing (where fitted) from side of the relay box then open up the insulating cover to gain access to the battery. 2 3 4 If corrosion (white, fluffy deposits) is evident, remove the cables from the battery terminals, clean them with a small wire brush, then refit them. Automotive stores sell a tool for cleaning the battery post . . . Electrical systems 4 Check all external lights and the horn. Refer to the appropriate Sections of Chapter 12 for details if any of the circuits are found to be inoperative. 4 Visually check all accessible wiring connectors, harnesses and retaining clips for security, and for signs of chafing or damage. 1 2 If a single indicator light, stop-light or headlight has failed, it is likely that a bulb has blown and will need to be replaced. Refer to Chapter 12 for details. If both stop lights have failed, it is possible that the switch has failed (see Chapter 12, Section 4). If more than one indicator light or tail light has failed it is likely that either a fuse has blown or that there is a fault in the circuit (see Chapter 12). Most fuses are located behind in the fusebox, behind the cover on the driver’s side of the facia; depress the locking button and remove the cover to gain access. Additional fuses can be found in the engine compartment relay box and fusible link housing. 3510 Vauxhall/Opel Omega The exterior of the battery should be inspected periodically for damage such as a cracked case or cover. Check the battery lead clamps for tightness to ensure good electrical connections and check the leads for signs of damage. . . . as well as the battery cable clamps If you need to check your brake lights and indicators unaided, back up to a wall or garage door and operate the lights. The reflected light should show if they are working properly. 3 To replace a blown fuse, remove it, where applicable, using the plastic tool provided. Fit a new fuse of the same rating, available from car accessory shops. It is important that you find the reason that the fuse blew (see Electrical fault finding in Chapter 12). 0•14 Weekly checks Tyre condition and pressure It is very important that tyres are in good condition, and at the correct pressure - having a tyre failure at any speed is highly dangerous. Tyre wear is influenced by driving style - harsh braking and acceleration, or fast cornering, will all produce more rapid tyre wear. As a general rule, the front tyres wear out faster than the rears. Interchanging the tyres from front to rear ("rotating" the tyres) may result in more even wear. However, if this is completely effective, you may have the expense of replacing all four tyres at once! Remove any nails or stones embedded in the tread before they penetrate the tyre to cause deflation. If removal of a nail does reveal that the tyre has been punctured, refit the nail so that its point of penetration is marked. Then immediately change the wheel, and have the tyre repaired by a tyre dealer. Regularly check the tyres for damage in the form of cuts or bulges, especially in the sidewalls. Periodically remove the wheels, and clean any dirt or mud from the inside and outside surfaces. Examine the wheel rims for signs of rusting, corrosion or other damage. Light alloy wheels are easily damaged by "kerbing" whilst parking; steel wheels may also become dented or buckled. A new wheel is very often the only way to overcome severe damage. 1 Tread Depth - visual check 2 Tread Depth - manual check 3 Tyre Pressure Check The original tyres have tread wear safety bands (B), which will appear when the tread depth reaches approximately 1.6 mm. The band positions are indicated by a triangular mark on the tyre sidewall (A). Alternatively, tread wear can be monitored with a simple, inexpensive device known as a tread depth indicator gauge. New tyres should be balanced when they are fitted, but it may become necessary to rebalance them as they wear, or if the balance weights fitted to the wheel rim should fall off. Unbalanced tyres will wear more quickly, as will the steering and suspension components. Wheel imbalance is normally signified by vibration, particularly at a certain speed (typically around 50 mph). If this vibration is felt only through the steering, then it is likely that just the front wheels need balancing. If, however, the vibration is felt through the whole car, the rear wheels could be out of balance. Wheel balancing should be carried out by a tyre dealer or garage. Check the tyre pressures regularly with the tyres cold. Do not adjust the tyre pressures immediately after the vehicle has been used, or an inaccurate setting will result. Tyre pressures are shown on page 0•17. Tyre tread wear patterns Shoulder Wear Centre Wear Uneven Wear Underinflation (wear on both sides) Under-inflation will cause overheating of the tyre, because the tyre will flex too much, and the tread will not sit correctly on the road surface. This will cause a loss of grip and excessive wear, not to mention the danger of sudden tyre failure due to heat build-up. Check and adjust pressures Incorrect wheel camber (wear on one side) Repair or renew suspension parts Hard cornering Reduce speed! Overinflation Over-inflation will cause rapid wear of the centre part of the tyre tread, coupled with reduced grip, harsher ride, and the danger of shock damage occurring in the tyre casing. Check and adjust pressures Front tyres may wear unevenly as a result of wheel misalignment. Most tyre dealers and garages can check and adjust the wheel alignment (or "tracking") for a modest charge. Incorrect camber or castor Repair or renew suspension parts Malfunctioning suspension Repair or renew suspension parts Unbalanced wheel Balance tyres Incorrect toe setting Adjust front wheel alignment Note: The feathered edge of the tread which typifies toe wear is best checked by feel. If you sometimes have to inflate your car’s tyres to the higher pressures specified for maximum load or sustained high speed, don’t forget to reduce the pressures to normal afterwards. 3510 Vauxhall/Opel Omega Weekly checks 0•15 Washer fluid level Screenwash additives not only keep the winscreen clean during foul weather, they also prevent the washer system freezing in cold weather - which is when you are likely to need it most. Don’t top up using plain water as the screenwash will become too diluted, and will 1 The reservoir for the windscreen/ tailgate/headlamps (as applicable) is located at the front of vehicle. The fluid level in the reservoir can be checked using the dipstick attached to the filler cap. freeze during cold weather. On no account use coolant antifreeze in the washer system this could discolour or damage paintwork. 2 When topping-up the reservoir, a screenwash additive should be added in the quantities recommended on the bottle. Wiper blades 1 Check the condition of the wiper blades; if they are cracked or show any signs of deterioration, or if the glass swept area is smeared, renew them. Wiper blades should be renewed annually. 2 To remove a windscreen wiper blade, pull the arm fully away from the screen until it locks. Swivel the blade through 90°, press the locking tab with your fingers and slide the blade out of the arm’s hooked end. 3510 Vauxhall/Opel Omega 0•16 Lubricants and fluids Lubricants and fluids Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual transmission: Early (pre 1999) vehicles: Up to number JP3097A01361659* . . . . . . . . . . . . . . . . . . . From number JP3097A01361659* . . . . . . . . . . . . . . . . . . . Later (1999 onwards) vehicles . . . . . . . . . . . . . . . . . . . . . . . . Multigrade engine oil, viscosity SAE 10W/40 to 15W/50 to API SG/CD or SH/CD (Duckhams QXR Premium Petrol Engine Oil or Duckhams Hypergrade Petrol Engine Oil) Ethylene glycol based antifreeze (Duckhams Antifreeze and Summer Coolant) Vauxhall transmission oil 19 40 704 Vauxhall transmission oil 19 40 764 Vauxhall transmission oil 19 40 768 Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vauxhall transmission fluid 19 40 763 (Duckhams ATF Autotrans III) Final drive unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 8 specifications Braking and clutch system . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic fluid DOT 4 (Duckhams Universal Brake and Clutch Fluid) Power steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vauxhall transmission fluid 19 40 700 (Duckhams ATF Autotrans III) *The identification number is stamped on the transmission housing. Note: There have been three different types of oil used in the transmission by Vauxhall. The different types of oil should never be mixed, and it is essential that the transmission is refilled either with the same type of oil as that drained, or the latest oil used in production from 1999 model year. If it is not known what type of oil has been drained, the transmission unit should be flushed before filling with the latest specification oil. To do this, refer to Chapter 7A, Section 2. Choosing your engine oil Engines need oil, not only to lubricate moving parts and minimise wear, but also to maximise power output and to improve fuel economy. By introducing a simplified and improved range of engine oils, Duckhams has taken away the confusion and made it easier for you to choose the right oil for your engine. HOW ENGINE OIL WORKS • Beating friction Without oil, the moving surfaces inside your engine will rub together, heat up and melt, quickly causing the engine to seize. Engine oil creates a film which separates these moving parts, preventing wear and heat build-up. • Cooling hot-spots Temperatures inside the engine can exceed 1000º C. The engine oil circulates and acts as a coolant, transferring heat from the hot-spots to the sump. • Cleaning the engine internally DUCKHAMS ENGINE OILS Good quality engine oils clean the inside of your engine, collecting and dispersing combustion deposits and controlling them until they are trapped by the oil filter or flushed out at oil change. For the driver who demands a premium quality oil for complete reassurance, we recommend synthetic formula Duckhams QXR Premium Engine Oils. For the driver who requires a straightforward quality engine oil, we recommend Duckhams Hypergrade Engine Oils. OIL CARE - FOLLOW THE CODE To handle and dispose of used engine oil safely, always: • Avoid skin contact with used engine oil. Repeated or prolonged contact can be harmful. • Dispose of used oil and empty packs in a responsible manner in an authorised disposal site. Call 0800 663366 to find the one nearest to you. Never tip oil down drains or onto the ground. 3510 Vauxhall/Opel Omega For further information and advice, call the Duckhams UK Helpline on 0800 212988. Tyre pressures 0•17 Tyre pressures Note: Pressures apply to original-equipment tyres only and may vary if any other make or type of tyre is fitted; check with the tyre manufacturer or supplier for correct pressures if necessary. Note: Tyre pressures must always be checked with the tyres cold to ensure accuracy. Saloon models 2.0 litre engine Up to 3 passengers (including driver) . . . . . . . . . . . . . . . . . . . . Fully loaded . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front 28.5 psi (2.0 bar) 36 psi (2.5 bar) Rear 28.5 psi (2.0 bar) 42 psi (2.9 bar) 2.5 and 3.0 litre engine Up to 3 passengers (including driver) . . . . . . . . . . . . . . . . . . . . Fully loaded . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.5 psi (2.2 bar) 36 psi (2.5 bar) 31.5 psi (2.2 bar) 42 psi (2.9 bar) 28.5 psi (2.0 bar) 33.0 psi (2.3 bar) 38.0 psi (2.6 bar) 31.5 psi (2.2 bar) 45.0 psi (3.1 bar) 45.0 psi (3.1 bar) 31.5 psi (2.2 bar) 34.0 psi (2.3 bar) 39.0 psi (2.7 bar) 34.0 psi (2.3 bar) 46.0 psi (3.2 bar) 46.0 psi (3.2 bar) 28.5 psi (2.0 bar) 33.0 psi (2.3 bar) 38.0 psi (2.6 bar) 31.5 psi (2.2 bar) 45.0 psi (3.1 bar) 45.0 psi (3.1 bar) Estate models 2.0 litre engine Up to 3 passengers (including driver) . . . . . . . . . . . . . . . . . . . . 4 or 5 passengers (including driver) and 60 kg of luggage . . . . Fully loaded . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine 195/65 R 15 tyres: Up to 3 passengers (including driver) . . . . . . . . . . . . . . . . . . . 4 or 5 passengers (including driver) and 60 kg of luggage . . . Fully loaded . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205/65 R 15 and 225/55 R 15 tyres: Up to 3 passengers (including driver) . . . . . . . . . . . . . . . . . . . 4 or 5 passengers (including driver) and 60 kg of luggage . . . Fully loaded . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3510 Vauxhall/Opel Omega 1•1 Chapter 1 Routine maintenance and servicing Contents Air filter element - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Automatic transmission fluid - renewal . . . . . . . . . . . . . . . . . . . . . . . 25 Automatic transmission fluid level - check . . . . . . . . . . . . . . . . . . . . 19 Auxiliary drivebelt - check and renewal . . . . . . . . . . . . . . . . . . . . . . . 6 Bodywork/underbody corrosion protection - check . . . . . . . . . . . . . 8 Brake fluid - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Coolant - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Driveshaft gaiter condition - check . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Engine oil and filter - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Exhaust system - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Front and rear disc brakes - pad wear check . . . . . . . . . . . . . . . . . . 5 Fuel filter - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Handbrake - shoe condition check . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Handbrake operation - check and adjustment . . . . . . . . . . . . . . . . . 9 Headlight and auxiliary driving light beam alignment - check . . . . . . 12 Lock and hinge lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Monitoring, lighting and signalling equipment - check . . . . . . . . . . . 4 Pollen filter - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Regular maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Remote control keyfob battery - renewal . . . . . . . . . . . . . . . . . . . . . 27 Road test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Spark plugs - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Suspension and steering condition and operation - check . . . . . . . . 10 Timing belt - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Underbonnet/underbody hose and fluid leak - check . . . . . . . . . . . . 7 Wheel alignment - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Wheel bolt torque - check and adjustment . . . . . . . . . . . . . . . . . . . . 11 1 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 3510 Vauxhall/Opel Omega Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 1•2 Servicing specifications Lubricants and fluids .................................. Refer to end of Weekly checks on page 0•16 Capacities Engine oil 2.0 litre engine: SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Engines with a one-piece sump . . . . . . . . . . . . . . . . . . . . . . . . . Engines with a two-piece sump . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Difference between MIN and MAX on dipstick (all engines) . . . . . . . . . . Cooling system 2.0 litre engine: SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 litres 4.5 litres 5.0 litres 5.75 litres 1.0 litre Manual transmission Automatic transmission 9.0 litres 8.8 litres 9.7 litres 8.8 litres 8.6 litres 9.5 litres Transmission Manual transmission (approximate) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 litres Automatic transmission (approximate): From dry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.4 litres After removing main sump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 litres Final drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 litre* *On models with limited-slip differential, observe the notes in Chapter 8 regarding the correct mixture of oil and additive to be used when refilling the final drive unit. Washer fluid reservoir Without headlight washers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . With headlight washers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litres 6.4 litres Fuel tank All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 litres Engine Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion G102 Cooling system Antifreeze mixture: 50% antifreeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55% antifreeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Note: Refer to antifreeze manufacturer for latest recommendations. Protection down to -37ºC Protection down to -45ºC Fuel system Air filter element: 2.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U595 Champion U601 Champion L225 Ignition system Spark plugs (gap not adjustable - see text) . . . . . . . . . . . . . . . . . . . . . . Champion RC10DMC Brakes Friction material minimum thickness: Front brake pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear brake pads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Handbrake shoes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torque wrench settings Automatic transmission fluid level plug . . . . . . . . . . . . . . . . . . . . . . . . . Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Roadwheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sump drain plug: 2.0 litre SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 litre DOHC engine: Hex-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torx-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine: Hex-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torx-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.0 mm including backing plate 6.0 mm including backing plate 1.0 mm excluding backing plate Nm 33 15 110 25 lbf ft 24 11 81 18 55 41 45 10 33 7 55 10 41 7 3510 Vauxhall/Opel Omega Maintenance schedule The maintenance intervals in this manual are provided with the assumption that you, not the dealer, will be carrying out the work. These are the minimum maintenance intervals recommended by us for vehicles driven daily. If you wish to keep your vehicle in peak condition at all times, you may wish to perform some of these procedures more often. We encourage frequent maintenance, because it enhances the efficiency, performance and resale value of your vehicle. If the vehicle is driven in dusty areas, used to tow a trailer, or driven frequently at slow speeds (idling in traffic) or on short journeys, 1•3 more frequent maintenance intervals are recommended. When the vehicle is new, and/or still within its warranty period, it should be serviced by a factory-authorised dealer service department, in order to preserve the factory warranty. Every 5000 miles (7500 km) or 6 months, whichever comes first Every 40 000 miles (60 000 km) or 4 years, whichever comes first m Engine oil and filter - renewal (Section 3) Carry out all the operations listed for the 15,000 km/12 month and the 30,000 km/2 year intervals, plus the following additional operations: Note: Vauxhall recommend that the engine oil and filter are changed every 10 000 miles or 12 months. However, oil and filter changes are good for the engine and we recommend that the oil and filter are renewed more frequently, especially if the vehicle is used on a lot of short journeys. Every 10 000 miles (15 000 km) or 12 months, whichever comes first m Monitoring, lighting and signalling equipment check (Section 4) m Front and rear brakes - pad and disc wear check (Section 5) m Auxiliary drivebelt condition and tension - check and adjust (Section 6)* m Underbonnet/underbody hose and fluid leak check (Section 7)* m Bodywork/underbody corrosion protection - check (Section 8)* m Handbrake operation - check and adjustment (Section 9)* m Suspension and steering condition and operation check (Section 10)* m Wheel bolt torque - check and adjustment (Section 11) m Headlight and auxiliary driving light beam alignment - check (Section 12)* m Road test (Section 13) m Wheel alignment - check (Section 14) m Exhaust system - check (Section 15)* * Note: On vehicles covering a high mileage (more than 20 000 m Spark plugs - renewal (Section 22)* m Fuel filter - renewal (Section 23) m Timing belt - renewal (Section 24)** * Note: On pre-1999 model year vehicles, renew the spark plugs every 40 000 miles (60 000 km) regardless of the time elapsed. **Note: Since the introduction of the Omega in 1994, Vauxhall have gradually increased the specified interval for timing belt renewal as follows: 1994 model year vehicle, 36 000 miles or 4 years, whichever comes first. 1995 and 1996 model year vehicles, 40 000 miles or 4 years, whichever comes first. 1997 model year vehicles onwards, 80 000 miles or 8 years, whichever comes first. However, if the vehicle is used mainly for short journeys or a lot of stop-start driving, or if the vehicle’s history is unknown, it is recommended that the earlier (1994 model year) recommendation is adhered to. The actual belt renewal interval is very much up to the individual owner but, bearing in mind that severe engine damage will result if the belt breaks in use, we recommend you err on the side of caution. Every 70 000 miles (105 000 km) or 7 years whichever comes first m Automatic transmission fluid - renewal (Section 25)* Note: This operation applies only to vehicles covering a high mileage (more than 20 000 miles/30 000 km annually) miles/30 000 km annually) carry out the items marked with an asterisk at the 12 month interval; carry out the items not marked with an asterisk every 10 000 miles/15 000 km, regardless of elapsed time. Every 2 years, regardless of mileage Every 20 000 miles (30 000 km) or 2 years, whichever comes first m Brake fluid - renewal (Section 26) m Remote control keyfob battery - renewal (Section 27) m Coolant - renewal (Section 28) Carry out all the operations listed for the 15,000 km/12 month interval, plus the following additional operations: m m m m m m Air filter element - renewal (Section 16) Pollen filter - renewal (Section 17) Lock and hinge lubrication (Section 18) Automatic transmission fluid level check (Section 19) Handbrake - shoe condition check (Section 20) Driveshaft gaiter condition - check (Section 21) 3510 Vauxhall/Opel Omega 1 1•4 Maintenance - component location Underbonnet view of a 2.0 litre DOHC engine model 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Engine oil filler cap Air cleaner Front suspension strut upper mounting Brake (and clutch) fluid reservoir Relay box Cooling system expansion tank Battery Fusible link housing Power steering pump Engine oil level dipstick Oil filter Alternator Airflow meter Throttle housing Power steering fluid reservoir Underbonnet view of a 2.5 litre engine model (3.0 litre engine similar) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 3510 Vauxhall/Opel Omega Engine oil filler cap Power steering fluid reservoir Front suspension strut upper mounting Relay box Fusible link housing Engine oil level dipstick Battery Multi-ram air intake system pre-volume chamber Airflow meter Air cleaner Cooling system expansion tank Brake (and clutch) fluid reservoir Exhaust gas recirculation (EGR) valve Inlet manifold Idle speed adjuster valve Maintenance - component location 1•5 Front underbody view (2.0 litre DOHC engine shown - others similar) 1 2 3 4 5 6 7 8 9 10 11 12 13 Exhaust front downpipe Oil filter Engine oil drain plug Air conditioning system compressor Front suspension lower arm Steering outer tie rod Steering drop arm Steering centre tie rod Steering idler Steering outer tie rod Manual transmission Oxygen sensor Transmission unit rear mounting crossmember 1 Rear underbody view (2.0 litre DOHC engine shown - others similar) 1 2 3 4 5 6 7 8 Exhaust tailpipe Fuel tank Final drive unit Fuel filter Rear shock absorber Driveshaft Rear suspension tie rod Rear suspension lower arm 9 Propeller shaft 10 Handbrake cable 3510 Vauxhall/Opel Omega 1•6 Maintenance procedures 1 General information 1 This Chapter is designed to help the home mechanic maintain his/her vehicle for safety, economy, long life and peak performance. 2 The Chapter contains a master maintenance schedule, followed by Sections dealing specifically with each task in the schedule. Visual checks, adjustments, component renewal and other helpful items are included. Refer to the accompanying illustrations of the engine compartment and the underside of the vehicle for the locations of the various components. 3 Servicing your vehicle in accordance with the mileage/time maintenance schedule and the following Sections will provide a planned maintenance programme, which should result in a long and reliable service life. This is a comprehensive plan, so maintaining some items but not others at the specified service intervals, will not produce the same results. 4 As you service your vehicle, you will discover that many of the procedures can and should - be grouped together, because of the particular procedure being performed, or because of the proximity of two otherwiseunrelated components to one another. For example, if the vehicle is raised for any reason, the exhaust can be inspected at the same time as the suspension and steering components. 5 The first step in this maintenance pro- gramme is to prepare yourself before the actual work begins. Read through all the Sections relevant to the work to be carried out, then make a list and gather all the parts and tools required. If a problem is encountered, seek advice from a parts specialist, or a dealer service department. 2 Regular maintenance compression test indicates serious internal engine wear, conventional maintenance as described in this Chapter will not greatly improve the performance of the engine, and may prove a waste of time and money, unless extensive overhaul work is carried out first. 4 The following series of operations are those most often required to improve the performance of a generally poor-running engine: Primary operations 1 If, from the time the vehicle is new, the routine maintenance schedule is followed closely, and frequent checks are made of fluid levels and high-wear items, as suggested throughout this manual, the engine will be kept in relatively good running condition, and the need for additional work will be minimised. 2 It is possible that there will be times when the engine is running poorly due to the lack of regular maintenance. This is even more likely if a used vehicle, which has not received regular and frequent maintenance checks, is purchased. In such cases, additional work may need to be carried out, outside of the regular maintenance intervals. 3 If engine wear is suspected, a compression test (refer to Chapter 2A, 2B or 2C, as applicable) will provide valuable information regarding the overall performance of the main internal components. Such a test can be used as a basis to decide on the extent of the work to be carried out. If, for example, a a) Clean, inspect and test the battery (refer to Weekly checks). b) Check all the engine-related fluids (refer to Weekly checks). c) Check the condition and tension of the auxiliary drivebelt (Section 6). d) Renew the spark plugs (Section 22). e) Check the condition of the air filter, and renew if necessary (Section 16). f) Renew the fuel filter (Section 23). g) Check the condition of all hoses, and check for fluid leak. 5 If the above operations do not prove fully effective, carry out the following secondary operations: Secondary operations All items listed under Primary operations, plus the following: a) Check the charging system (refer to Chapter 5A). b) Check the ignition system (refer to Chapter 5B). c) Check the fuel system (refer to Chapter 4A). Every 5000 miles or 6 months 3 Engine oil and filter renewal 2 1 Frequent oil and filter changes are the most important preventative maintenance procedures which can be undertaken by the DIY owner. As engine oil ages, it becomes diluted and contaminated, which leads to premature engine wear. 2 Before starting this procedure, gather together all the necessary tools and materials. 3.5 Removing the sump drain plug Also make sure that you have plenty of clean rags and newspapers handy, to mop up any spills. Ideally, the engine oil should be warm, as it will drain more easily, and more built-up sludge will be removed with it. Take care not to touch the exhaust or any other hot parts of the engine when working under the vehicle. To avoid any possibility of scalding, and to protect yourself from possible skin irritants and other harmful contaminants in used engine oils, it is advisable to wear gloves when carrying out this work. 3 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands (see Jacking and Vehicle Support). Undo the retaining screws and remove the undercover from beneath the engine unit. 4 Remove the oil filler cap. 5 Using a spanner, or preferably a suitable socket and bar, slacken the drain plug about half a turn (see illustration). Position the draining container under the drain plug, then remove the plug completely (see Haynes Hint). 6 Allow some time for the oil to drain, noting that it may be necessary to reposition the container as the oil flow slows to a trickle. 7 After all the oil has drained, wipe the drain plug and the sealing washer with a clean rag. 3510 Vauxhall/Opel Omega Examine the condition of the sealing washer, and renew it if it shows signs of scoring or other damage which may prevent an oil-tight seal. Clean the area around the drain plug opening, and refit the plug complete with the washer and tighten it to the specified torque. 8 Move the container into position under the oil filter. On 2.0 litre engines the filter is located on the front end of the engine, where As the drain plug releases from the threads, move it quickly away so that the stream of oil running out of the sump goes into the container and not over your arm Every 5000 miles 1•7 3.8 Oil filter location - 2.0 litre engine 3.11a Lubricate the sealing ring of the new filter with a smear of engine oil . . . 3.11b . . . then screw the filter on by hand only (2.5 litre engine shown) it is screwed onto the oil pump housing, and on 2.5 and 3.0 litre engines it is screwed onto the left-hand side of the cylinder block (see illustration). 9 Use an oil filter removal tool to slacken the filter initially, then unscrew it by hand the rest of the way. Empty the oil from the old filter into the container. 10 Use a clean rag to remove all oil, dirt and sludge from the filter sealing area on the engine. 11 Apply a light coating of clean engine oil to the sealing ring on the new filter, then screw the filter into position on the engine. Tighten the filter firmly by hand only - do not use any tools (see illustrations). If a genuine filter is being fitted and the special oil filter tool (Tool no. KM-726A - a socket which fits over the end of the filter) is available, tighten the filter to the specified torque. 12 Refit the undercover, tightening its retaining screws securely, then remove the old oil and all tools from under the vehicle before lowering the vehicle to the ground. 13 Fill the engine through the filler hole, using the correct grade and type of oil (refer to Weekly Checks for details of topping-up). Pour in half the specified quantity of oil first, then wait a few minutes for the oil to drain into the sump. Continue to add oil, a small quantity at a time, until the level is up to the lower mark on the dipstick. Adding approximately a further 1.0 litre will bring the level up to the upper mark on the dipstick. 14 Start the engine and run it for a few minutes, while checking for leaks around the oil filter seal and the sump drain plug. Note that there may be a delay of a few seconds before the low oil pressure warning light goes out when the engine is first started, as the oil circulates through the new oil filter and the engine oil galleries before the pressure builds up. 15 Stop the engine, and wait a few minutes for the oil to settle in the sump once more. With the new oil circulated and the filter now completely full, recheck the level on the dipstick, and add more oil as necessary. 16 Dispose of the used engine oil safely with reference to General repair procedures. 1 Every 10 000 miles or 12 months 4 Monitoring, lighting and signalling equipment check 1 1 Turn the ignition switch to the second position and check that the instrument panel CHECK lamp lights up and then extinguishes after 4 approximately seconds. If the lamp fails to extinguish, observe the fault description message(s) displayed and rectify the cause. 2 Start the engine and check that all tell-tale system operation/fault lamps extinguish. Note that some lamps (such as the automatic transmission sport programme, or traction control system lamps) may remain lit, depending on the driving mode selected; consult your drivers handbook for the exact meaning of each lamp. 3 Release handbrake, depress the brake pedal and check that the brake lights fault display extinguishes. 4 Switch on all interior and exterior lights in turn and check their operation. Pay particular attention to the tail lamps, fog lamps, brake lamps, main and dipped beam headlamps, position lamps and front and rear direction indicators. Renew any blown bulbs with reference to Chapter 12. 5 Finally, check the operation of the horn. 5 Front and rear brakes pad and disc wear check 2 Front brakes 1 Firmly apply the handbrake, select first gear or P, then jack up the front of the vehicle and support it securely on axle stands (see Jacking and Vehicle Support). Remove the front roadwheels. 2 For a quick check, the pad thickness can be carried out via the inspection hole on the front surface of each caliper (see illustration). Using a steel rule, measure the thickness of each pad lining, including the backing plate. This must not be less than that indicated in the Specifications. 3 The view through the caliper inspection hole gives only a rough indication of the state of the brake pads. For a comprehensive check, the brake pads should be removed and cleaned. The operation of the caliper can then also be checked, and the condition of the brake disc itself can be fully examined on both sides. Chapter 9 contains a detailed description of how the brake discs should be checked for wear and/or damage. 4 If any pad’s friction material is worn to the specified thickness or less, all four pads must be renewed as an axle set; for example - if the pads in the left hand caliper are found to be worn, those in the right hand caliper must also be renewed, regardless of their condition. Refer to Chapter 9 for details. 5 On completion, refit the roadwheels and lower the vehicle to the ground. Rear brakes 5.2 The brake pad wear can be assessed by observing the thickness of the friction material, visible through the inspection aperture at the front of the brake caliper 3510 Vauxhall/Opel Omega 6 Chock the front wheels, then jack up the rear of the vehicle and support it securely on axle stands (see Jacking and Vehicle Support). Remove the rear roadwheels. 1•8 Every 10 000 miles 6.3a On 2.0 litre engines check that the drivebelt tensioner arm indicator (2) is correctly positioned between the stops (1 and 3) on the backplate 7 Proceed as described in paragraphs 2 to 4 inclusive, noting that the inspection aperture is at the rear of the caliper. 8 On completion, refit the rear roadwheels and lower the vehicle to the ground. 6 Auxiliary drivebelt check and renewal 3 Check 1 Although the drivebelt tension is automatically adjusted by the spring-loaded tensioner, the belt itself should still be regularly checked for damage or deterioration. 2 With the engine stopped, inspect the full length of the drivebelt for cracks and separation of the belt plies. It will be necessary to turn the engine (using a spanner or socket and bar on the crankshaft pulley bolt) in order to move the belt from the pulleys so that the belt can be inspected thoroughly. Twist the belt between the pulleys so that both sides can be viewed. Also check for fraying, and glazing which gives the belt a 6.12 Lever the tensioner away from the belt then slip the belt off from its pulleys (2.5 litre engine shown) 6.3b On 2.5 and 3.0 litre engines ensure the stop (1) on the drivebelt tensioner mounting plate is in between the lugs (2) on the arm shiny appearance. Check the pulleys for nicks, cracks, distortion and corrosion. 3 Check the position of the drivebelt tensioner assembly arm in relation to the backplate. On 2.0 litre engines the arm indicator should be in between the stops on the backplate and should be free to move. On 2.5 and 3.0 litre engines the stop on the tensioner mounting plate should be positioned between the lugs on the arm and the arm should be free to move (see illustrations). 4 If the belt shows signs of wear or damage, or the tensioner arm is against the stop, the belt must be renewed. Renewal 2.0 litre engine 5 Prior to removal make a note of the correct routing of the belt around the various pulleys. If the belt is to be reused, also mark the direction of rotation on the belt to ensure the belt is refitted the same way around. 6 Using a suitable spanner or socket fitted to the tensioner pulley centre bolt, lever the tensioner away from the belt until there is sufficient slack to enable the belt to be slipped off from the pulleys. Carefully release the tensioner pulley until it is against its stop then remove the belt from the vehicle. If necessary, the tensioner can be locked in the released position by aligning the arm hole with the hole in the backplate and inserting a suitable tool/pin. 7 Manoeuvre the belt into position, routing it correctly around the pulleys; if the original belt is being fitted use the marks made prior to removal to ensure it is fitted the correct way around. 8 Lever the tensioner roller back against is spring, and seat the belt on the pulleys. Ensure the belt is centrally located on all pulleys then slowly release the tensioner 3510 Vauxhall/Opel Omega pulley until the belt is correctly tensioned. Do not allow the tensioner to spring back and stress the belt. 9 Check the tensioner arm is correctly positioned in relation to the backplate (see paragraph 3). 2.5 and 3.0 litre engine 10 Remove the multi-ram air intake system pre-volume chamber and the secondary air injection system front connecting pipe as described in the relevant Parts of Chapter 4. 11 Prior to removal make a note of the correct routing of the belt around the various pulleys. If the belt is to be reused, also mark the direction of rotation on the belt to ensure the belt is refitted the same way around. 12 Using a suitable spanner or socket fitted to the tensioner pulley centre bolt, lever the tensioner away from the belt until there is sufficient slack to enable the belt to be slipped off from the pulleys (see illustration). Carefully release the tensioner pulley until it is against its stop then remove the belt from the vehicle. 13 Manoeuvre the belt into position, routing it correctly around the pulleys; if the original belt is being fitted use the marks made prior to removal to ensure it is fitted the correct way around. 14 Lever the tensioner roller back against is spring, and seat the belt on the pulleys. Ensure the belt is centrally located on all pulleys then slowly release the tensioner pulley until the belt is correctly tensioned. Do not allow the tensioner to spring back and stress the belt. 15 Check the tensioner arm is correctly positioned in relation to the backplate (see paragraph 3) then refit the secondary air injection system connecting pipe and the multi-ram air intake system pre-volume chamber as described in the relevant part of Chapter 4. Every 10 000 miles 7 Underbonnet/underbody hose and fluid leak check 2 Cooling system Warning: Refer to the safety information given in Safety First and Chapter 3 before disturbing any of the cooling system components. 1 Carefully check the radiator and heater coolant hoses along their entire length. Renew any hose which is cracked, swollen or which shows signs of deterioration. Cracks will show up better if the hose is squeezed. Pay close attention to the clips that secure the hoses to the cooling system components. Hose clips that have been over-tightened can pinch and puncture hoses, resulting in cooling system leaks (see illustration). 2 Inspect all the cooling system components (hoses, joint faces, etc) for leaks. Where any problems of this nature are found on system components, renew the component or gasket with reference to Chapter 3. A leak in the cooling system will usually manifest itself as white or rust-coloured, crusty deposits on the area adjacent to the leak Inspect the petrol tank and filler neck for punctures, cracks and other damage. The connection between the filler neck and tank is especially critical. Sometimes a rubber filler neck or connecting hose will leak due to loose retaining clamps or deteriorated rubber. 6 Carefully check all rubber hoses and metal fuel lines leading away from the petrol tank. Check for loose connections, deteriorated hoses, kinked lines, and other damage. Pay particular attention to the vent pipes and hoses, which often loop up around the filler neck and can become blocked or kinked, making tank filling difficult. Follow the fuel supply and return lines to the front of the vehicle, carefully inspecting them all the way for signs of damage or corrosion. Renew damaged sections as necessary. Engine oil 7 Inspect the area around the camshaft cover, cylinder head, oil filter and sump joint faces. Bear in mind that, over a period of time, some very slight seepage from these areas is to be expected - what you are really looking for is any indication of a serious leak caused by gasket failure. Engine oil seeping from the base of the timing belt cover or the transmission bellhousing may be an indication of crankshaft or transmission input shaft oil seal failure. Should a leak be found, renew the failed gasket or oil seal by referring to the appropriate Chapters in this manual. 1•9 Automatic transmission fluid 8 Check the hoses leading to the transmission fluid cooler for leakage. Look for deterioration caused by corrosion and damage from grounding, or debris thrown up from the road surface. Automatic transmission fluid is a thin oil and is usually red in colour. Check the area around the propeller shaft seal at the rear of the transmission for signs of fluid leakage. Should a leak be found, check the fluid level as described in Section 19 then rectify the cause of leakage as soon as possible. Power assisted steering (PAS) fluid 9 Examine the hose running between the fluid reservoir and the power steering pump, and the return hose running from the steering rack to the fluid reservoir. Also examine the high pressure supply hose between the pump and the steering rack. 10 Check the condition of each hose carefully. Look for deterioration caused by corrosion and damage from grounding, or debris thrown up from the road surface. 11 Pay particular attention to crimped unions, and the area surrounding the hoses that are secured with adjustable worm drive clips. Like automatic transmission fluid, PAS fluid is a thin oil, and is usually red or light brown in colour. 1 Fuel system Warning: Refer to the safety information given in Safety First and Chapter 4A before disturbing any of the fuel system components. 3 Petrol leaks can be difficult to pinpoint, unless the leakage is significant and hence easily visible. Fuel tends to evaporate quickly once it comes into contact with air, especially in a hot engine bay. Small drips can disappear before you get a chance to identify the point of leakage. If you suspect that there is a fuel leak from the area of the engine bay, leave the vehicle overnight then start the engine from cold, with the bonnet open. Metal components tend to shrink when they are cold, and rubber seals and hoses tend to harden, so any leaks will be more apparent whilst the engine is warming up from a cold start. 4 Check all fuel lines at their connections to the fuel rail, fuel pressure regulator and fuel filter (petrol models), Examine each rubber fuel hose along its length for splits or cracks. Check for leakage from the crimped joints between rubber and metal fuel lines. Examine the unions between the metal fuel lines and the fuel filter housing. Also check the area around the fuel injectors for signs of O-ring leakage. 5 To identify fuel leaks between the fuel tank and the engine bay, the vehicle should raised and securely supported on axle stands. 7.1 Possible causes of coolant hose failure 3510 Vauxhall/Opel Omega 1•10 Every 10 000 miles Air conditioning refrigerant Warning: Refer to the safety information given in Safety First and Chapter 3, regarding the dangers of disturbing any of the air conditioning system components. 12 The air conditioning system is filled with a liquid refrigerant, which is retained under high pressure. If the air conditioning system is opened and depressurised without the aid of specialised equipment, the refrigerant will immediately turn into gas and escape into the atmosphere. If the liquid comes into contact with your skin, it can cause severe frostbite. In addition, the refrigerant contains substances which are environmentally damaging; for this reason, it should not be allowed to escape into the atmosphere in an uncontrolled fashion. 13 Any suspected air conditioning system leaks should be immediately referred to a Vauxhall dealer or air conditioning specialist. Leakage will be shown up as a steady drop in the level of refrigerant in the system. 14 Note that water may drip from the condenser drain pipe, underneath the car, immediately after the air conditioning system has been in use. This is normal, and should not be cause for concern. Brake fluid Warning: Refer to the safety information given in Safety First and Chapter 9, regarding the dangers of handling brake fluid. 15 Examine the area surrounding the brake pipe unions at the master cylinder for signs of leakage. Check the area around the base of fluid reservoir, for signs of leakage caused by seal failure. Also examine the brake pipe unions at the ABS hydraulic unit. 16 If fluid loss is evident, but the leak cannot be pinpointed in the engine bay, the brake calipers and underbody brake lines should be carefully checked with the vehicle raised and supported on axle stands (see illustration). Leakage of fluid from the braking system is a serious fault that must be rectified immediately. 17 Brake/clutch hydraulic fluid is a toxic substance with a watery consistency. New fluid is almost colourless, but it becomes darker with age and use. 7.16 Inspecting the flexible hose connection to a front brake caliper leakage. Should a leak be found, check the differential fluid level as described in Chapter 8 then rectify the cause of leakage as soon as possible. Unidentified fluid leaks 20 If there are signs that a fluid of some description is leaking from the vehicle, but you cannot identify the type of fluid or its exact origin, park the vehicle overnight and slide a large piece of card underneath it. Providing that the card is positioned in roughly the right location, even the smallest leak will show up on the card. Not only will this help you to pinpoint the exact location of the leak, it should be easier to identify the fluid from its colour. Bear in mind, though, that the leak may only be occurring when the engine is running! Vacuum hoses 21 Although the braking system is hydraulically-operated, the brake servo unit amplifies the effort applied at the brake pedal, by making use of the vacuum in the inlet manifold, generated by the engine. Vacuum is ported to the servo by means of a large-bore hose. Any leaks that develop in this hose will reduce the effectiveness of the braking system, and may affect the running of the engine. 22 In addition, a number of the underbonnet components, particularly the emission control components, are driven by vacuum supplied from the inlet manifold via narrow-bore rubber Manual transmission fluid 18 Check the area around the propeller shaft seal at the rear of the transmission for signs of fluid leakage. Should a leak be found, check the transmission fluid level as described in Chapter 7A then rectify the cause of leakage as soon as possible. Final drive unit differential fluid 19 Check the area around the driveshaft and propeller shaft seals, and the flange seal on the rear of the final drive unit for signs of fluid 9.5 Handbrake cable adjustment nut (arrowed) 3510 Vauxhall/Opel Omega and plastic hoses. A leak in a vacuum hose means that air is being drawn into the hose (rather than escaping from it) and this makes leakage very difficult to detect. One method is to use an old length of vacuum hose as a kind of stethoscope - hold one end close to (but not in!) your ear and use the other end to probe the area around the suspected leak. When the end of the hose is directly over a vacuum leak, a hissing sound will be heard clearly through the hose. Care must be taken to avoid contacting hot or moving components, as the engine must be running, when testing in this manner. Renew any vacuum hoses that are found to be defective. 8 Bodywork/underbody corrosion protection check 5 1 This work should be carried out by a Vauxhall/Opel dealer in order to validate the vehicle warranty. The work includes a thorough inspection of the vehicle paintwork and underbody for damage and corrosion 9 Handbrake operation check and adjustment 2 1 Chock the front wheels, then jack up the rear of the vehicle and support it securely on axle stands (see Jacking and Vehicle Support). Remove the rear roadwheels. 2 Fully release the handbrake lever, then apply it to the third notch. Check that both rear wheels can still rotate by attempting to turn them by hand (ensure that the transmission is in neutral). Release the handbrake lever. 3 Fully apply the handbrake lever, so that the rear wheels are locked, counting how many notches the lever passes through. If the handbrake lever passes through more than seven notches before the rear wheels lock, adjustment is required. 4 If adjustment is necessary, first fully release the handbrake, then pull it up to the third notch. 5 Working underneath the vehicle, unbolt the exhaust system heat shields from the floorpan. Locate the handbrake cable adjustment nut, at the cable compensation bar, above the propeller shaft. Fully slacken the adjustment nut so that there is a small amount of clearance between it and the compensation bar (see illustration). 6 Working on one brake disc at a time, position the hole in the disc over the serrated adjustment nut on the adjuster at the top of the backplate. Using a screwdriver inserted through the hole, turn the nut until the brake disc locks, then turn the nut in opposite direction until the disc is just free (see illustration). Repeat the adjustment on the remaining rear brake. Every 10 000 miles 7 Check that the handbrake lever is still positioned on the third notch, then working underneath the vehicle, tighten the handbrake cable adjustment nut against the compensation bar, until the handbrake shoes just start to take effect - test for this by turning the brake discs by hand. 8 Refit the rear wheels, then carry out a final check of the handbrake adjustment; the rear wheels should turn freely with the lever applied to the third notch and should be fully locked before passing through the seventh notch. Tighten the wheel bolts to the specified torque then lower the car the ground. Check the operation of the handbrake before using the vehicle on the road. 9 After fitting new handbrake shoes, the shoes should be bedded-in by driving a short distance (approximately 300 metres) at low speed with the handbrake lever lightly applied. Check, and if necessary adjust the handbrake again after completing the bedding-in. 10 Suspension and steering condition and operation check 2 Front suspension and steering check 1 Raise the front of the vehicle, and securely support it on axle stands (see Jacking and Vehicle Support). 2 Visually inspect the balljoint dust covers and the steering rack-and-pinion gaiters for splits, chafing or deterioration. Any wear of these components will cause loss of lubricant, together with dirt and water entry, resulting in rapid deterioration of the balljoints or steering gear. 3 Check the power steering fluid hoses for chafing or deterioration, and the pipe and hose unions for fluid leaks. Also check for signs of fluid leakage under pressure from the steering gear rubber gaiters, which would indicate failed fluid seals within the steering gear. 4 Grasp the roadwheel at the 12 o’clock and 6 o’clock positions, and try to rock it (see illustration). Very slight free play may be felt, but if the movement is appreciable, further investigation is necessary to determine the source. Continue rocking the wheel while an assistant depresses the footbrake. If the movement is now eliminated or significantly reduced, it is likely that the hub bearings are at fault. If the free play is still evident with the footbrake depressed, then there is wear in the suspension joints or mountings. 5 Now grasp the wheel at the 9 o’clock and 3 o’clock positions, and try to rock it as before. Any movement felt now may again be caused by wear in the hub bearings or the steering track-rod balljoints. If the outer balljoint is worn, the visual movement will be obvious. If the inner joint is suspect, it can be felt by 1•11 Shock absorber check 9.6 Adjusting the handbrake screws using a screwdriver through the hole in the disc/hub flange placing a hand over the rack-and-pinion rubber gaiter and gripping the track-rod. If the wheel is now rocked, movement will be felt at the inner joint if wear has taken place. 6 Using a large screwdriver or flat bar, check for wear in the suspension mounting bushes by levering between the relevant suspension component and its attachment point. Some movement is to be expected, as the mountings are made of rubber, but excessive wear should be obvious. Also check the condition of any visible rubber bushes, looking for splits, cracks or contamination of the rubber. 7 With the car standing on its wheels, have an assistant turn the steering wheel back-andforth, about an eighth of a turn each way. There should be very little, if any, lost movement between the steering wheel and roadwheels. If this is not the case, closely observe the joints and mountings previously described. In addition, check the steering column universal joints for wear, and also check the rack-and-pinion steering gear itself. Rear suspension check 8 Chock the front wheels, then jack up the rear of the vehicle and support securely on axle stands (see Jacking and Vehicle Support). 9 Working as described previously for the front suspension, check the rear hub bearings, the suspension bushes and the strut or shock absorber mountings (as applicable) for wear. 10.4 To check for play in the wheel bearing, grasp the roadwheel at the 12 o’clock and 6 o’clock positions, and try to rock it 3510 Vauxhall/Opel Omega 10 Check for any signs of fluid leakage around the shock absorber body, or from the rubber gaiter around the piston rod. Should any fluid be noticed, the shock absorber is defective internally, and should be renewed. Note: Shock absorbers should always be renewed in pairs on the same axle. 11 The efficiency of the shock absorber may be checked by bouncing the vehicle at each corner. Generally speaking, the body will return to its normal position and stop after being depressed. If it rises and returns on a rebound, the shock absorber is probably suspect. Also examine the shock absorber upper and lower mountings for any signs of wear. 11 Wheel bolt torque check and adjustment 2 Note: As well as being potentially damaging to the vehicle’s roadwheels, over-tightened wheel bolts may cause problems if you have to change a wheel by the side of the road. By ensuring that the wheel bolts are tightened to the correct torque, you could save yourself a lot of time and trouble in an emergency situation. 1 Slacken the front wheel securing bolts slightly, then apply the handbrake firmly, raise the front of the vehicle, and securely support it on axle stands (see Jacking and Vehicle Support). 2 Fully slacken the each of the wheel bolts in turn and clear any dirt of debris from the threads. Re-insert the wheel bolts and tighten them to the specified torque setting using a good quality torque wrench. 3 Repeat the operation at the opposite wheel, then lower the car the ground. 4 Chock the front wheels, then jack up the rear of the vehicle and support securely on axle stands (see Jacking and Vehicle Support). Repeat the operations described in paragraphs 2 and 3. 12 Headlight and auxiliary driving light beam alignment - check 5 1 Badly adjusted headlights and/or foglights cause poor visibility and can dazzle other road users. Accurate adjustment of the headlight and auxiliary driving light beams is only possible using optical beam-setting equipment, and this work should therefore be carried out by a Vauxhall/Opel dealer or suitably-equipped workshop. 2 For reference, the headlights can be adjusted using the adjuster assemblies fitted to the front upper outer mounting and to the rear inner mounting. The inner screw is for horizontal adjustment and the outer one for 1 1•12 Every 10 000 miles vertical adjustment. When adjusting the headlight aim, ensure that the facia -mounted range adjustment switch is set to position 0 (see paragraph 3). 3 All models have an electric headlight beam adjustment range system, controlled via a rotary switch in the facia*. The recommended settings are as follows. 0 1 2 3 Front seat(s) occupied All seats occupied All seats occupied, and load in luggage compartment Driver’s seat occupied and load in the luggage compartment *On models built from 1998 onwards with Xenon headlights, an automatic headlamp range adjustment system is fitted, to which no manual adjustment can be made; see Chapter 12 for details. 13 Road test 1 Instruments and electrical equipment 1 Check the operation of all instruments and electrical equipment. 2 Make sure that all instruments read correctly, and switch on all electrical equipment in turn, to check that it functions properly. Steering and suspension 3 Check for any abnormalities in the steering, suspension, handling or road feel. 4 Drive the vehicle, and check that there are no unusual vibrations or noises. 5 Check that the steering feels positive, with no excessive sloppiness, or roughness, and check for any suspension noises when cornering and driving over bumps. Drivetrain 6 Check the performance of the engine, clutch, transmission and driveshafts. 7 Listen for any unusual noises from the engine, clutch and transmission. 8 Make sure that the engine runs smoothly when idling, and that there is no hesitation when accelerating. 9 Check that, where applicable, the clutch action is smooth and progressive, that the drive is taken up smoothly, and that the pedal travel is not excessive. Also listen for any noises when the clutch pedal is depressed. 10 Check that all gears can be engaged smoothly without noise, and that the gear lever action is not abnormally vague or notchy. 11 On automatic transmission models, make sure that all gearchanges occur smoothly, without snatching, and without an increase in engine speed between changes. Check that all of the gear positions can be selected with the vehicle at rest. If any problems are found, they should be referred to a Vauxhall/Opel dealer. Check the operation and performance of the braking system 12 Make sure that the vehicle does not pull to one side when braking, and that the wheels do not lock prematurely when braking hard. 13 Check that there is no vibration through the steering when braking. 14 Check that the handbrake operates correctly, without excessive movement of the lever, and that it holds the vehicle stationary on a slope. 15 Test the operation of the brake servo unit as follows. Depress the footbrake four or five times to exhaust the vacuum, then start the engine. As the engine starts, there should be a noticeable give in the brake pedal as vacuum builds up. Allow the engine to run for at least two minutes, and then switch it off. If the brake pedal is now depressed again, it should be possible to detect a hiss from the servo as the pedal is depressed. After about four or five applications, no further hissing should be heard, and the pedal should feel considerably harder. 14 Wheel alignment check 5 1 Accurate wheel alignment is essential for positive, accurate steering, stable road holding and to prevent abnormal tyre wear. Wheel alignment checking is carried out with the car loaded to its kerbside weight, and with the tyre pressures correctly adjusted. 2 The front toe setting, front camber angle, rear toe setting and rear camber angle are all adjustable, but can only be checked using specialised equipment; work of this nature should therefore be entrusted to a garage or suitably-equipped tyre specialist. 15 Exhaust system check 2 1 Park the vehicle on a level surface and switch off the engine. Chock the front wheels, then raise the rear of the vehicle and support it securely on axle stands - refer to Jacking and vehicle support in Reference. 2 With the engine cold (wait at least an hour after switching off the engine), check the complete exhaust system from the engine to the end of the tailpipe. 3 Check the exhaust pipes and connections for evidence of leaks, severe corrosion and damage. Make sure that all brackets and mountings are in good condition, and that all relevant nuts and bolts are tight. Leakage at any of the joints or in other parts of the system will usually show up as a black, sooty stain in the vicinity of the leak. 4 Rattles and vibrations can often be traced to the exhaust system. Tap the silencer units with a soft mallet and listen for noises caused by corroded or displaced baffle material. Do not strike the catalytic converter, as this may damage the ceramic block inside. 5 Carefully rock the pipes and silencers from side to side on their mountings. If the components are able to come into contact with the body or suspension parts, look for broken or worn rubber mountings. Every 20 000 miles or 2 years 16 Air filter element renewal 1 1 The air cleaner is located in the front righthand corner of the engine compartment. 2 Release the retaining clip and disconnect the intake duct from the air cleaner housing. 3 Release the retaining clips then lift the air cleaner cover and filter element out of position. 4 Wipe out the casing and the cover. 5 Fit the new filter, noting that the rubber locating flange should be uppermost, and secure the cover with the clips. 6 Reconnect the intake duct to the air cleaner housing and secure it in position with the retaining clip. 17 Pollen filter renewal 2 1 Open the bonnet and support it in the upright position. 2 Carefully peel the rubber beading away from the bulkhead seam, at the rear of the engine compartment, on the drivers side of the car (see illustration). 3510 Vauxhall/Opel Omega 17.2 Carefully peel the rubber beading away from the bulkhead seam Every 20 000 miles 1•13 17.3 Hinge the grille panel upwards 17.4a Release the clips . . . 17.4b . . . then withdraw the pollen filter element 3 Hinge the grille panel upwards to expose the pollen filter housing (see illustration). 4 Release the clips at either side of the housing, then withdraw the pollen filter element (see illustrations). 5 Slide the new filter element into the housing and secure it in position with the clips. 6 Hinge the grille panel down over the housing and press the rubber beading into position on the bulkhead seam. 2 Lightly lubricate the bonnet release mechanism and exposed section of inner cable with a smear of grease. 3 Check the security and operation of all hinges, latches and locks, adjusting them where required. Check the operation of the central locking system. 4 Check the condition and operation of the tailgate/boot lid struts, renewing them both if either is leaking or no longer able to support the tailgate/boot lid securely when raised. Unscrew the plug and clean it. 4 The oil level should reach the lower edge of the level plug hole. If topping up is necessary, add the specified type of oil through the level plug hole until oil begins to trickle out. 5 Allow the excess oil to drain out then fit a new sealing washer to the level plug and refit it to the sump, tightening it to the specified torque. 18 Lock and hinge lubrication 1 1 Work around the vehicle and lubricate the hinges of the bonnet, doors and tailgate/boot lid with a light machine oil. 19.3 Removing the automatic transmission unit fluid level plug 19 Automatic transmission fluid level check 3 1 The transmission fluid level must be checked with the engine warm. For the check to be accurate, Vauxhall state that the transmission fluid temperature should ideally be 60ºC but can be anywhere in the range of 45 to 85ºC (113 to 185ºF). 2 Take the vehicle on a short run to warm the engine and transmission unit up to operating temperature. On your return position the vehicle over an inspection pit, on vehicle ramps, or jack it up, but make sure that it is level. 3 Start the engine and allow it to idle. Wipe clean the area around the level plug which is fitted to the right-hand side of the transmission main sump (see illustration). 20 Handbrake shoe condition check 1 Refer to the information given in Chapter 9 for details. 21 Driveshaft gaiter condition check 2 1 Chock the front wheels, then jack up the rear of the vehicle and support it on axle stands. 2 With the handbrake released turn each wheel separately and check the driveshaft rubber gaiters for splits and damage. Check that the securing clips are in good condition and shows no signs of damage or corrosion. Driveshaft grease sprayed in a line along the underside of the car, above the joint is a sign that the gaiter has failed and requires renewal. Every 40 000 miles or 4 years 22 Spark plugs renewal 3 1 The correct functioning of the spark plugs is vital for the correct running and efficiency of the engine. It is essential that the plugs fitted are appropriate for the engine; suitable types are specified at the beginning of this Chapter, or in the vehicle’s Owner’s Handbook. If the correct type is used and the engine is in good condition, the spark plugs should not need attention between scheduled replacement intervals. Spark plug cleaning is rarely necessary, and should not be attempted unless specialised equipment is available, as damage can easily be caused to the firing ends. 2 On 2.0 litre DOHC engines, undo the retaining screws and lift off the spark plug cover from the top of the camshaft cover (see illustration). 3 On 2.5 and 3.0 litre engines, carry out the following operations referring to Chapter 4A for further information. a) Remove the idle speed control valve. b) On models with air conditioning, undo the retaining bolt and remove the air conditioning pipe retaining clip from the left-hand cylinder head. 3510 Vauxhall/Opel Omega 22.2 On 2.0 litre DOHC engine remove the spark plug cover to gain access to the plugs 1 1•14 Every 40 000 miles 22.4a Unclip the tool (arrowed) . . . 22.4b . . . and use it to pull the HT leads off from the plugs (2.5 litre engine shown) 22.10 The multi-electrode plugs fitted as standard should not be adjusted c) Undo the bolts securing the wiring harness cover to the inlet manifold and position the harness clear of the left-hand cylinder head spark plugs. d) Unscrew the union nut and disconnect the braking system servo unit vacuum hose from the manifold. e) To improve access to the plugs on the right-hand cylinder head, unclip the accelerator cable from its mounting bracket then unbolt and remove the mounting bracket from the inlet manifold. 4 On all engines, if the marks on the originalequipment spark plug (HT) leads cannot be seen, mark the leads to correspond to the cylinder the lead serves. Pull the leads from the plugs by gripping the end fitting, not the lead, otherwise the lead connection may be fractured. On 2.0 litre DOHC engines and all 2.5 and 3.0 litre engines use the tool clipped to one of the plug leads to pull the HT leads from the plugs (see illustrations). 5 It is advisable to remove the dirt from the spark plug recesses using a clean brush, vacuum cleaner or compressed air before removing the plugs, to prevent dirt dropping into the cylinders. 6 Unscrew the plugs from the cylinder head using a spark plug spanner, suitable box spanner or a deep socket and extension bar. Keep the socket aligned with the spark plug if it is forcibly moved to one side, the ceramic insulator may be broken off. As each plug is removed, examine it as follows. 7 Examination of the spark plugs will give a good indication of the condition of the engine. If the insulator nose of the spark plug is clean and white, with no deposits, this is indicative of a weak mixture or too hot a plug (a hot plug transfers heat away from the electrode slowly, a cold plug transfers heat away quickly). 8 If the tip and insulator nose are covered with hard black-looking deposits, then this is indicative that the mixture is too rich. Should the plug be black and oily, then it is likely that the engine is fairly worn, as well as the mixture being too rich. 9 If the insulator nose is covered with light tan to greyish-brown deposits, then the mixture is correct and it is likely that the engine is in good condition. 10 All engines are fitted with multi-electrode plugs as standard by Vauxhall (see illustration). On these plugs, the electrode gaps are all preset and no attempt should be made to bend the electrodes. 11 If non-standard single electrode plugs are to be installed (this is not recommended), the spark plug electrode gap is of considerable importance. If the gap is too large or too small, the size of the spark and its efficiency will be seriously impaired and it will not perform correctly under all engine speed and load conditions. The gap should be set to the value specified by the manufacturer. 12 To set the gap on a single electrode plug, measure it with a feeler blade or spark plug gap gauge and then carefully bend the outer plug electrode until the correct gap is achieved. The centre electrode should never be bent, as this may crack the insulator and cause plug failure, if nothing worse. If using feeler blades, the gap is correct when the appropriate-size blade is a firm sliding fit (see illustrations). 13 Special spark plug electrode gap adjusting tools are available from most motor accessory shops, or from some spark plug manufacturers (see illustration). 14 Before fitting the spark plugs, check that the threaded connector sleeves are tight, and that the plug exterior surfaces and threads are clean. 22.12a If single electrode plugs are being fitted, check the electrode gap using a feeler gauge . . . 22.12b . . . or a wire gauge . . . 22.13 . . . and if necessary adjust the gap by bending the electrode 3510 Vauxhall/Opel Omega It is very often difficult to insert spark plugs into their holes without crossthreading them. To avoid this possibility, fit a short length of 5⁄16 inch internal diameter rubber hose over the end of the spark plug. The flexible hose acts as a universal joint to help align the plug with the plug hole. Should the plug begin to cross-thread, the hose will slip on the spark plug, preventing thread damage to the aluminium cylinder head Every 40 000 miles 1•15 necessary) the air conditioning pipe bracket. d) Refit the idle speed control valve. 23 Fuel filter renewal 22.17 On 2.0 litre DOHC engines refit the spark plug cover and securely tighten its retaining screws 15 Remove the rubber hose (if used), and tighten the plug to the specified torque using the spark plug socket and a torque wrench. Refit the remaining spark plugs in the same manner. 16 Securely reconnect the HT leads in their correct order. 17 On 2.0 litre DOHC engines refit the spark plug cover and securely tighten its retaining screws (see illustration). 18 On 2.5 and 3.0 litre engines carry out the following operations, referring to Chapter 4A for further information. a) Refit the accelerator cable bracket to the manifold and adjust the accelerator cable. b) Reconnect the servo unit vacuum hose to the manifold and tighten to the specified torque. c) Refit the wiring cover bolts and (where 3 1 The fuel filter is located under the rear of the vehicle, just in front of the fuel tank. 2 Depressurise the fuel system as described in Chapter 4A. 3 Chock the front wheels, then jack up the rear of the vehicle and support on axle stands (see Jacking and Vehicle Support). 4 Release the retaining clip holding the filter to the underbody. Before removing the filter, note the orientation of the fuel flow direction arrow (see illustration). 5 Position a suitable container below the fuel filter, to catch spilt fuel. 6 Release the connectors and disconnect the fuel hoses from the fuel filter, noting their locations to ensure correct refitting (see illustration). A Vauxhall/Opel special tool is available to disconnect the hose connectors, but provided care it taken, the connections can be released using a pair of pliers or a screwdriver. Be prepared for fuel spillage, and take adequate fire precautions. 7 Withdraw the filter from under the vehicle. 8 Fit the quick-release fitting clips to the new filter offer up the filter making sure the flow 23.6 Depress the quick-release fitting tabs and detach the hoses from the fuel filter direction arrow on the filter body pointing in the direction of fuel flow (see illustration). 9 Securely clip both hoses onto the filter then secure the filter in position with the retaining clip. 10 Start the engine and check the filter hose unions for signs of leaks. If leakage is evident, stop the engine immediately and rectify the problem without delay. 11 If all is well, stop the engine and lower the vehicle to the ground. 24 Timing belt renewal 1 Refer to the information given in Chapter 2A, 2B or 2C (as applicable). 23.8 On refitting ensure the arrow (1) on the filter is pointing in the direction of fuel flow and the quick-release fitting clips (2) are correctly fitted Every 70 000 miles or 7 years 25 Automatic transmission fluid - renewal 23.4 Release the retaining clip and free the fuel filter from the body 1 Renew the transmission fluid and filter assembly as described in Section 2 of Chapter 7B. 3510 Vauxhall/Opel Omega 1 1•16 Every 2 years Every 2 years, regardless of mileage 26 Brake fluid renewal 3 Warning: Brake hydraulic fluid can harm your eyes and damage painted surfaces, so use extreme caution when handling and pouring it. Do not use fluid that has been standing open for some time, as it absorbs moisture from the air. Excess moisture can cause a dangerous loss of braking effectiveness. 1 The procedure is similar to that for the bleeding of the hydraulic system as described in Chapter 9. 2 Working as described in Chapter 9, open the first bleed screw in the sequence, and pump the brake pedal gently until nearly all the old fluid has been emptied from the master cylinder reservoir. Top-up to the MAX level with new fluid, and continue pumping until only the new fluid remains in the reservoir, and new fluid can be seen emerging from the bleed screw. Tighten the screw, and top the reservoir level up to the MAX level line. Old hydraulic fluid is invariably much darker in colour than the new, making it easy to distinguish the two. 3 Work through all the remaining bleed screws in the sequence until new fluid can be seen at all of them. Be careful to keep the master cylinder reservoir topped-up to above the MIN level at all times, or air may enter the system and greatly increase the length of the task. 4 When the operation is complete, check that all bleed screws are securely tightened, and that their dust caps are refitted. Wash off all traces of spilt fluid, and recheck the master cylinder reservoir fluid level. 5 Check the operation of the brakes before taking the car on the road. 27 Remote control keyfob battery renewal 1 Caution: The following procedure must be completed within 3 minutes, otherwise the remote control unit will have to be reprogrammed. 1 Using a small flat-bladed screwdriver, prise the battery cover from the remote control unit. 2 Note how the battery is fitted, then carefully remove it from the contacts. 3 Fit the new battery and refit the cover making sure that it clips fully onto the base. 5 If the coolant has been drained for a reason other than renewal, then provided it is clean and less than two years old, it can be re-used, though this is not recommended. Cooling system flushing 6 If coolant renewal has been neglected, or if the antifreeze mixture has become diluted, then in time, the cooling system may gradually lose efficiency, as the coolant passages become restricted due to rust, scale deposits, and other sediment. The cooling system efficiency can be restored by flushing the system clean. 7 The radiator should be flushed independently of the engine, to avoid unnecessary contamination. Radiator flushing 28 Coolant renewal 3 Cooling system draining Warning: Wait until the engine is cold before starting this procedure. Do not allow antifreeze to come in contact with your skin, or with the painted surfaces of the vehicle. Rinse off spills immediately with plenty of water. Never leave antifreeze lying around in an open container, or in a puddle in the driveway or on the garage floor. Children and pets are attracted by its sweet smell, but antifreeze can be fatal if ingested. 1 With the engine completely cold, remove the expansion tank filler cap. Turn the cap anti-clockwise, wait until any pressure remaining in the system is released, then unscrew it and lift it off. 2 Where applicable, remove the engine undershield, then position a suitable container beneath the left hand side of the radiator. 3 Open the drain plug at the base of the radiator, and allow the coolant to drain into the container (see illustration). 4 When the flow of coolant stops, close the drain plug securely. 8 Disconnect the top and bottom hoses and any other relevant hoses from the radiator, with reference to Chapter 3. 9 Insert a garden hose into the radiator top inlet. Direct a flow of clean water through the radiator, and continue flushing until clean water emerges from the radiator bottom outlet. 10 If after a reasonable period, the water still does not run clear, the radiator can be flushed with a good proprietary cleaning agent. It is important that the manufacturer’s instructions are followed carefully. If the contamination is particularly bad, remove the radiator, insert the hose in the radiator bottom outlet, and reverse-flush the radiator. Engine flushing 11 Remove the thermostat as described in Chapter 3 then, if the radiator top hose has been disconnected from the engine, temporarily reconnect the hose. 12 With the top and bottom hoses disconnected from the radiator, insert a garden hose into the radiator top hose. Direct a clean flow of water through the engine, and continue flushing until clean water emerges from the radiator bottom hose. 13 On completion of flushing, refit the thermostat and reconnect the hoses with reference to Chapter 3. Cooling system filling 14 Before attempting to fill the cooling system, make sure that all hoses and clips are in good condition, and that the clips are tight. Note that an antifreeze mixture must be used all year round, to prevent corrosion of the engine components. 15 Remove the expansion tank filler cap, and top the level up to the KALT/COLD mark. 6-cylinder engine models 28.3 Open the drain plug at the base of the radiator (arrowed) 28.18 Slowly fill the system via the expansion tank filler neck, until the coolant level again reaches the KALT/COLD mark on the side of the expansion tank 3510 Vauxhall/Opel Omega 16 Disconnect the heater supply (upper) hose from the bulkhead connection (see Chapter 3). 17 Pour coolant into the disconnected heater hose with the aid of a funnel, until no more coolant will flow in, then reconnect the heater hose to the bulkhead connection and tighten the clip securely. Every 2 years 18 Slowly fill the system via the expansion tank filler neck, until the coolant level again reaches the KALT/COLD mark on the side of the expansion tank (see illustration). All models 19 Refit and tighten the expansion tank filler cap. 20 Start the engine, and allow it to run until it reaches normal operating temperature (until the cooling fan cuts in and out). The cooling system will bleed automatically as the engine warms up. 21 Stop the engine, and allow it to cool, then re-check the coolant level with reference to Weekly checks. Top-up the level if necessary and refit the expansion tank filler cap. Where applicable, refit the engine undershield. Antifreeze mixture 22 The antifreeze should always be renewed at the specified intervals. This is necessary not only to maintain the antifreeze properties, but also to prevent corrosion which would otherwise occur as the corrosion inhibitors become progressively less effective. 23 Always use an ethylene-glycol based antifreeze which is suitable for use in mixedmetal cooling systems. The quantity of antifreeze and levels of protection are given in the Specifications. 1•17 24 Before adding antifreeze, the cooling system should be completely drained, preferably flushed, and all hoses checked for condition and security. 25 After filling with antifreeze, a label should be attached to the expansion tank, stating the type and concentration of antifreeze used, and the date installed. Any subsequent topping-up should be made with the same type and concentration of antifreeze. 26 Do not use engine antifreeze in the windscreen/tailgate washer system, as it will cause damage to the vehicle paintwork. A screenwash additive should be added to the washer system in the quantities stated on the bottle. 1 3510 Vauxhall/Opel Omega 2A•1 Chapter 2 Part A: 2.0 litre SOHC engine in-car repair procedures Contents Camshaft cover - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 4 Camshaft followers and hydraulic tappets - removal, inspection and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Camshaft housing and camshaft - removal, inspection and refitting 10 Camshaft oil seal - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Compression test - description and interpretation . . . . . . . . . . . . . . 2 Crankshaft oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Crankshaft pulley - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 5 Cylinder head - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 12 Engine oil and filter - renewal . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Engine oil level check . . . . . . . . . . . . . . . . . . . . . . .See Weekly checks Engine/transmission mountings - inspection and renewal . . . . . . . . 17 Flywheel/driveplate - removal, inspection and refitting . . . . . . . . . . . 15 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Oil pump - removal, overhaul and refitting . . . . . . . . . . . . . . . . . . . . 14 Sump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Timing belt - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Timing belt covers - removal and refitting . . . . . . . . . . . . . . . . . . . . . 6 Timing belt tensioner and sprockets - removal and refitting . . . . . . . 8 Top dead centre (TDC) for No 1 piston - locating . . . . . . . . . . . . . . . 3 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications 2A General Engine type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manufacturer’s engine code: Models with a catalytic converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . Models not fitted with a catalytic converter* . . . . . . . . . . . . . . . . . . . Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direction of crankshaft rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compression ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . *This model was never available in the UK Four-cylinder, in-line, water-cooled. Single overhead camshaft, beltdriven, acting on hydraulic tappets X20SE 20SE 86 mm 86 mm 1998 cc 1-3-4-2 (No 1 cylinder at timing belt end) Clockwise (viewed from timing belt end of engine) 10:1 85 kW at 5400 rpm 178 Nm at 2800 rpm Compression pressures Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum difference between any two cylinders . . . . . . . . . . . . . . . . . . 12 to 15 bar (174 to 218 psi) 1 bar (15 psi) Camshaft Endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum permissible radial run-out . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.09 to 0.21 mm 0.04 mm Lubrication system Oil pump type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Minimum permissible oil pressure at idle speed, with engine at operating temperature (oil temperature of at least 80°C) . . . . . . . . Oil pump clearances: Gear teeth clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear type, driven directly from crankshaft 1.5 bar (22 psi) 0.08 to 0.15 mm 0.03 to 0.10 mm 3510 Vauxhall/Opel Omega 2A•2 2.0 litre SOHC engine in-car repair procedures Torque wrench settings Camshaft cover bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Camshaft sprocket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Camshaft thrustplate bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Camshaft housing end cover bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Connecting rod big-end bearing cap bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coolant pump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankcase breather tube bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft pulley bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft sensor rotor bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft sprocket bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder head bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Driveplate bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine/transmission mountings: Left- and right-hand mountings: Mounting-to-subframe nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mounting-to-mounting bracket nut . . . . . . . . . . . . . . . . . . . . . . . . . Mounting bracket-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . Rear mounting: Mounting-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . Mounting-to-crossmember nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . Crossmember-to-body bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine to transmission support bracket bolts: Bracket-to-engine bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bracket-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine-to-transmission unit bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flywheel bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main bearing cap bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil pump: Retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pump cover screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil pressure relief valve bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil pump pick-up/strainer bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Spark plug heatshields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sump bolts: Retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Drain plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt cover bolts: Outer cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt tensioner bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nm 8 45 8 8 lbf ft 6 33 6 6 35 Angle-tighten a further 45° Angle-tighten a further 15° 25 25 20 13 26 18 18 15 10 130 Angle-tighten a further 40 to 50° 96 25 Angle-tighten a further 90° Angle-tighten a further 90° Angle-tighten a further 90° 18 55 Angle-tighten a further 30° Angle-tighten a further 15° 41 55 40 60 41 30 44 40 20 45 30 15 33 40 22 60 30 16 44 65 Angle-tighten a further 30° Angle-tighten a further 15° 48 50 Angle-tighten a further 45° Angle-tighten a further 15° 15 37 11 8 6 50 8 25 6 4 37 6 18 8 55 6 41 4 6 20 3 4 15 3510 Vauxhall/Opel Omega 2.0 litre SOHC engine in-car repair procedures 2A•3 1 General information Repair operations possible with the engine in the car 9 The following operations can be carried out without having to remove the engine from the vehicle: How to use this Chapter 1 This Part of Chapter 2 is devoted to in-car repair procedures for the engine. All procedures concerning engine removal and refitting, and engine block/cylinder head overhaul can be found in Chapter 2D. 2 Most of the operations included in this Part are based on the assumption that the engine is still installed in the car. Therefore, if this information is being used during a complete engine overhaul, with the engine already removed, many of the steps included here will not apply. Engine description 3 The engine is a single overhead camshaft, four-cylinder, in-line unit, mounted at the front of the car with the clutch/transmission (as applicable) on its rear. 4 The cylinder block is of the dry-liner type. The crankshaft is supported within the cylinder block on five shell-type main bearings. Thrustwashers are fitted to number 3 main bearing, to control crankshaft endfloat. 5 The connecting rods are attached to the crankshaft by horizontally split shell-type bigend bearings, and to the pistons by interference-fit gudgeon pins. The aluminium alloy pistons are of the slipper type, and are fitted with three piston rings, comprising two compression rings and a scraper-type oil control ring. 6 The camshaft runs directly in the camshaft housing, which is mounted on top of the cylinder head, and driven by the crankshaft via a toothed rubber timing belt (which also drives the coolant pump). The camshaft operates each valve via a follower. Each follower pivots on a hydraulic self-adjusting valve lifter (tappet) which automatically adjusts the valve clearance. 7 Lubrication is by pressure-feed from a gear-type oil pump, which is mounted on the front end of the crankshaft. It draws oil through a strainer located in the sump, and then forces it through an externally mounted full-flow cartridge-type filter. The oil flows into galleries in the main bearing cap bridge arrangement and cylinder block/crankcase, from where it is distributed to the crankshaft (main bearings) and camshaft. The big-end bearings are supplied with oil via internal drillings in the crankshaft, while the camshaft bearings also receive a pressurised supply. The camshaft lobes and valves are lubricated by splash, as are all other engine components. 8 A semi-closed crankcase ventilation system is employed; crankcase fumes are drawn from cylinder head cover, and passed via a hose to the inlet manifold. a) Removal and refitting of the cylinder head. b) Removal and refitting of the timing belt and sprockets. c) Renewal of the camshaft oil seal. d) Removal and refitting of the camshaft housing and camshaft. e) Removal and refitting of the sump. f) Removal and refitting of the connecting rods and pistons*. g) Removal and refitting of the oil pump. h) Renewal of the crankshaft oil seals. i) Renewal of the engine mountings. j) Removal and refitting of the flywheel/driveplate. * Although the operation marked with an asterisk can be carried out with the engine in the car after removal of the sump, it is better for the engine to be removed, in the interests of cleanliness and improved access. For this reason, the procedure is described in Chapter 2D. 2 Compression test description and interpretation 3 1 When engine performance is down, or if misfiring occurs which cannot be attributed to the ignition or fuel systems, a compression test can provide diagnostic clues as to the engine’s condition. If the test is performed regularly, it can give warning of trouble before any other symptoms become apparent. 2 The engine must be fully warmed-up to normal operating temperature, the battery must be fully charged, and the spark plugs must be removed (see Chapter 1). The aid of an assistant will also be required. 3 Ensure the ignition is switched off then disable the ignition system by disconnecting the wiring connector from the DIS module (see Chapter 5B) and the fuel system by removing the fuel pump relay from the engine compartment relay box (see Chapter 4A, Section 13). 4 Fit a compression tester to the number 1 cylinder spark plug hole the type of tester which screws into the plug thread is to be preferred. 5 Have the assistant hold the throttle wide open and crank the engine on the starter motor; after one or two revolutions, the compression pressure should build up to a maximum figure, and then stabilise. Record the highest reading obtained. 6 Repeat the test on the remaining cylinders, recording the pressure in each. 7 All cylinders should produce very similar pressures; any difference greater than that 3510 Vauxhall/Opel Omega specified indicates the existence of a fault. Note that the compression should build up quickly in a healthy engine; low compression on the first stroke, followed by graduallyincreasing pressure on successive strokes, indicates worn piston rings. A low compression reading on the first stroke, which does not build up during successive strokes, indicates leaking valves or a blown head gasket (a cracked head could also be the cause). Deposits on the undersides of the valve heads can also cause low compression. 8 If the pressure in any cylinder is reduced to the specified minimum or less, carry out the following test to isolate the cause. Introduce a teaspoonful of clean oil into that cylinder through its spark plug hole, and repeat the test. 9 If the addition of oil temporarily improves the compression pressure, this indicates that bore or piston wear is responsible for the pressure loss. No improvement suggests that leaking or burnt valves, or a blown head gasket, may be to blame. 10 A low reading from two adjacent cylinders is almost certainly due to the head gasket having blown between them; the presence of coolant in the engine oil will confirm this. 11 If one cylinder is about 20 per cent lower than the others, and the engine has a slightly rough idle, a worn camshaft lobe could be the cause. 12 If the compression reading is unusually high, the combustion chambers are probably coated with carbon deposits. If this is the case, the cylinder head should be removed and decarbonised. 13 On completion of the test, refit the spark plugs (see Chapter 1), refit the fuel pump relay and reconnect the wiring connector to the DIS module. 3 Top dead centre (TDC) for No 1 piston locating 3 1 In its travel up and down its cylinder bore, Top Dead Centre (TDC) is the highest point that each piston reaches as the crankshaft rotates. While each piston reaches TDC both at the top of the compression stroke and again at the top of the exhaust stroke, for the purpose of timing the engine, TDC refers to the piston position (usually number 1) at the top of its compression stroke. 2 Number 1 piston (and cylinder) is at the front (timing belt) end of the engine, and its TDC position is located as follows. Note that the crankshaft rotates clockwise when viewed from the front of the vehicle. 3 Disconnect the battery negative terminal. If necessary, remove all the spark plugs as described in Chapter 1 to enable the engine to be easily turned over. 4 To gain access to the camshaft sprocket timing mark, remove the timing belt outer cover as described in Section 6. 2A 2A•4 2.0 litre SOHC engine in-car repair procedures 5 Using a socket and extension bar on the crankshaft sprocket bolt, turn the crankshaft whilst keeping an eye on the camshaft sprocket. Rotate the crankshaft until the timing mark on the camshaft sprocket is correctly aligned with the cutout on the top of the timing belt rear cover and the mark on the crankshaft sprocket rim is correctly aligned with the cutout on the oil pump housing (see illustration). 6 With the crankshaft pulley and camshaft sprocket timing marks positioned as described, the engine is positioned with No1 piston at TDC on its compression stroke. 4 Camshaft cover removal and refitting 2 not lever between the cover and camshaft housing mating surfaces - if necessary, gently tap the cover sideways to free it. Recover the gasket; if it shows signs of damage or deterioration it must be renewed. Removal Refitting 1 Release the retaining clip and disconnect the breather hose from the camshaft cover. 2 Slacken and remove the retaining bolts, noting the correct fitted location of any clips or brackets retained by the bolts (as applicable) then lift the camshaft cover from the camshaft housing. If the cover is stuck, do 3 Prior to refitting, examine the inside of the cover for a build-up of oil sludge or any other contamination, and if necessary clean the cover with paraffin, or a water-soluble solvent. Examine the condition of the crankcase ventilation filter inside the camshaft cover, and clean as described for the inside of the cover if clogging is evident (if desired, the filter can be removed from the cover, after removing the securing bolts). Dry the cover thoroughly before refitting. 4 Ensure the cover is clean and dry and seat the gasket in the cover recess then refit the cover to the camshaft housing, ensuring the gasket remains correctly seated. 5 Refit the retaining bolts, ensuring all relevant clips/brackets are correctly positioned, and tighten them to the specified torque working in a diagonal sequence. 6 Reconnect the breather hose securely to the cover. 5 Crankshaft pulley removal and refitting 2 Removal 1 Remove the auxiliary drivebelt as described in Chapter 1. Prior to removal, mark the direction of rotation on the belt to ensure the belt is refitted the same way around. 2 Slacken and remove the small retaining bolts securing the pulley to the crankshaft sprocket and remove the pulley from the engine. If necessary, prevent crankshaft rotation by holding the sprocket retaining bolt with a suitable socket. Refitting 3 Seat the crankshaft pulley on the sprocket and tighten its retaining bolts to the specified torque. 4 Refit the auxiliary drivebelt as described in Chapter 1 using the mark made prior to removal to ensure the belt is fitted the correct way around. 6 Timing belt covers removal and refitting 3 Outer cover Removal 3.5 Align the camshaft sprocket timing mark with the cutout on the timing belt cover (1) and align the crankshaft sprocket mark with the cutout on the oil pump housing (2) to position No1 piston at TDC on its compression stroke 3510 Vauxhall/Opel Omega 1 Remove the crankshaft pulley as described in Section 5. 2 Undo the retaining bolt and free the wiring harness guide from the top of the timing belt cover. 2.0 litre SOHC engine in-car repair procedures 2A•5 7.3 Slacken the timing belt tensioner bolt (1) and rotate the tensioner clockwise using an Allen key in the arm cutout (2) 3 Undo the remaining retaining bolts then unclip the timing belt outer cover and remove it from the engine. Refitting 4 Refitting is the reverse of removal, ensuring the auxiliary drivebelt is fitted the same way around as it was prior removal. Rear cover Removal 5 Remove the camshaft and crankshaft timing belt sprockets and the timing belt tensioner as described in Section 8. 6 Free the crankshaft sensor wiring from the base of the timing belt rear cover, noting its correct routing. 7 Slacken and remove the bolts securing the rear cover to the camshaft housing and oil pump housing and remove the cover from the engine. Refitting 8 Refitting is the reverse of removal, tightening the cover retaining bolts to the specified torque. Ensure the crankshaft sensor wiring is correctly routed before refitting the timing belt components. 7.8 Tension the belt by rotating the tensioner arm fully anticlockwise until the pointer is positioned as shown 2 Position No 1 cylinder at TDC on its compression stroke as described in Section 3. 3 Slacken the timing belt tensioner bolt. Using an Allen key, rotate the tensioner arm clockwise to its stop, to relieve the tension in the timing belt, and hold it in position by securely tighten the retaining bolt (see illustration). 4 Slide the timing belt off from its sprockets and remove it from the engine. If the belt is to be re-used, use white paint or similar to mark the direction of rotation on the belt. Do not rotate the crankshaft or camshaft until the timing belt has been refitted. 5 Check the timing belt carefully for any signs of uneven wear, splitting or oil contamination, and renew it if there is the slightest doubt about its condition. If the engine is undergoing an overhaul and has covered 40 000 miles or it was more than 4 years since the original belt was fitted, renew the belt as a matter of course, regardless of its apparent condition (from 1997 onwards the belt renewal interval was increased to 80 000 miles or 8 years). If signs of oil contamination are found, trace the source of the oil leak and rectify it, then wash down the engine timing belt area and all related components to remove all traces of oil. Refitting 7 Timing belt removal and refitting 3 Note: The timing belt must be removed and refitted with the engine cold. Removal 1 Disconnect the battery negative terminal then remove the timing belt outer cover as described in Section 6. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 6 On reassembly, thoroughly clean the timing belt sprockets then check that the camshaft sprocket timing mark is still correctly aligned with the rear cover cutout and the crankshaft sprocket mark is still aligned with the mark on the oil pump housing. 7 Fit the timing belt over the crankshaft and camshaft sprockets, ensuring that the belt left-hand run is taut (ie, all slack is on the tensioner pulley side of the belt), then fit the belt over the coolant pump sprocket and tensioner pulley. Do not twist the belt sharply while refitting it. Ensure that the belt teeth are correctly seated centrally in the sprockets, and that the timing marks remain in alignment. If a used belt is being refitted, ensure that the 3510 Vauxhall/Opel Omega arrow mark made on removal points in the normal direction of rotation, as before. 8 Slacken the timing belt tensioner bolt to release the tensioner spring. Rotate the tensioner arm anti-clockwise until the tensioner pointer is fully over against its stop, without exerting any excess strain on the belt (see illustration). Hold the tensioner in position and securely tighten its retaining bolt. 9 Check the sprocket timing marks are still correctly aligned. If adjustment is necessary, release the tensioner again then disengage the belt from the sprockets and make any necessary adjustments. 10 Using a socket on the crankshaft sprocket bolt, rotate the crankshaft smoothly through two complete turns (720º) in the normal direction of rotation to settle the timing belt in position. 11 Check that both the camshaft and crankshaft sprocket timing marks are correctly realigned then slacken the tensioner bolt again. 12 If a new timing belt is being fitted, adjust the tensioner so that the pointer is aligned with either the cutout or NEW marking (depending on type of tensioner fitted) on the backplate (see illustration). Hold the tensioner in the correct position and tighten its retaining bolt to the specified torque. Rotate the crankshaft smoothly through another two complete turns in the normal direction of rotation, to bring the sprocket timing marks back into alignment. Check that the tensioner pointer is still aligned with the backplate cutout/marking (as applicable). 13 If the original belt is being refitted, adjust the tensioner so that the pointer is either positioned 4 mm to the left of the cutout or is aligned with the USED marking (depending on the type of tensioner fitted) on the backplate (see illustration 7.12). Hold the tensioner in the correct position and tighten its retaining bolt to the specified torque. Rotate the crankshaft smoothly through another two complete turns in the normal direction of 2A 2A•6 2.0 litre SOHC engine in-car repair procedures this can be achieved in one of two ways as follows. a) Make up a sprocket-holding tool using two lengths of steel strip (one long, the other short), and three nuts and bolts; one nut and bolt forms the pivot of a forked tool, with the remaining two nuts and bolts at the tips of the ‘forks’ to engage with the sprocket spokes as shown (see illustration). b) Remove the camshaft cover as described in Section 4 and hold the camshaft with an open-ended spanner on the flats provided. 3 Unscrew the retaining bolt and washer and remove the sprocket from the end of the camshaft. Refitting 4 Prior to refitting check the oil seal for signs of damage or leakage, if necessary, renewing it as described in Section 9. 5 Refit the sprocket to the end of the camshaft, aligning its cutout with the camshaft locating pin, then refit the retaining bolt and washer (see illustration). 6 Tighten the sprocket retaining bolt to the specified torque whilst prevent rotation using the method employed on removal. 7 Refit the timing belt as described in Section 7 then (where necessary) refit the camshaft cover as described in Section 4. 7.12 Ensure the timing belt tensioner arm (1) is correctly positioned in relation to the backplate cutout/marking (2) as described in text A Correct position for new belt - engines with an unmarked tensioner B Correct position for new belt - engines with a marked tensioner rotation, to bring the sprocket timing marks back into alignment. Check that the tensioner pointer is still correctly positioned in relation to the backplate cutout/marking (as applicable). 14 If the tensioner pointer is not correctly positioned in relation to the backplate, repeat the procedure in paragraph 12 (new belt) or 13 (original belt) (as applicable). 15 Once the tensioner arm and backplate remain correctly aligned, refit the timing belt cover and crankshaft pulley as described in Sections 5 and 6. C Correct position for used belt - engines with an unmarked tensioner D Correct position for used belt - engines with a marked tensioner 8 Timing belt tensioner and sprockets removal and refitting 3 Camshaft sprocket Removal 1 Remove the timing belt as described in Section 7. 2 The camshaft must be prevented from turning as the sprocket bolt is unscrewed, and Crankshaft sprocket Note: A new crankshaft sprocket retaining bolt will be required on refitting. Removal 8 Remove the timing belt as described in Section 7. 9 The crankshaft must be prevented from turning as the sprocket bolt is unscrewed (the bolt is very tight), and this can be achieved in anyone of the following ways. a) Use the holding tool described in paragraph 2 securing the tool to the sprocket with two bolts screwed into opposite pulley retaining bolt holes. b) On manual transmission models have an assistant select top gear and apply the brakes firmly. c) If the engine is removed from the vehicle or the transmission unit has been removed the flywheel/driveplate can be locked as described in Section 15. 10 Unscrew the retaining bolt and washer and remove the crankshaft sprocket from the end of the crankshaft. Discard the bolt; a new one must be used on refitting. If necessary, remove the sprocket Woodruff key from the crankshaft end and slide off the spacer. Refitting 8.2 Using a home-made sprocket holding tool to retain the camshaft sprocket whilst the bolt is slackened 8.5 Refit the camshaft sprocket making sure the locating pin (1) engages with the sprocket hole (2) 3510 Vauxhall/Opel Omega 11 Slide the spacer (where removed) onto the crankshaft then refit the Woodruff key to the crankshaft slot. 12 Align the sprocket with the key and slide it into position, ensuring the sprocket flange is facing outwards. Fit the washer and new retaining bolt. 2.0 litre SOHC engine in-car repair procedures 2A•7 13 Lock the crankshaft by the method used on removal, and tighten the sprocket retaining bolt to the specified stage 1 torque setting then angle-tighten the bolt through the specified stage 2 angle, using a socket and extension bar. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy. If a gauge is not available, use white paint to make alignment marks between the bolt head and sprocket prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 14 Refit the timing belt as described in Section 7. Tensioner assembly Removal 15 Remove the timing belt as described in Section 7. 16 Slacken and remove the retaining bolt and remove the tensioner assembly from the engine. 9.2 Removing the camshaft oil seal 9.4 Fitting a new camshaft oil seal engine oil, and press it into position using a suitable tubular drift (such as a socket) which bears only on the hard outer edge of the seal (see illustration). Take care not to damage the seal lips during fitting; note that the seal lips should face inwards. 5 Refit the camshaft sprocket as described in Section 8. whether this is a chance worth taking. 2 With the camshaft housing removed, undo the retaining bolts and remove the end cover and gasket from the rear of the housing. Discard the gasket, a new one should be used on refitting. 3 Measure the camshaft endfloat by inserting feeler gauges between the thrustplate and the camshaft; if the endfloat is not within the limits given in the Specifications then the thrustplate will need to be renewed. Unscrew the two retaining bolts then slide out the camshaft thrustplate, noting which way round it is fitted (see illustrations). 4 Carefully withdraw the camshaft from the rear of the housing, taking care not to damage the bearing journals (see illustration). Refitting 17 Fit the tensioner to the engine, making sure that the lug on the backplate is correctly located in the oil pump housing hole. Ensure the tensioner is correctly seated then refit the retaining bolt. Using an Allen key, rotate the tensioner arm clockwise to its stop then securely tighten the retaining bolt. 18 Refit the timing belt as described in Section 7. 9 Camshaft oil seal renewal 3 1 Remove the camshaft sprocket as described in Section 8. 2 Carefully punch or drill two small holes opposite each other in the oil seal. Screw a self-tapping screw into each, and pull on the screws with pliers to extract the seal (see illustration). 3 Clean the seal housing, and polish off any burrs or raised edges which may have caused the seal to fail in the first place. 4 Lubricate the lips of the new seal with clean 10.3a Undo the retaining bolts (arrowed) . . . 10 Camshaft housing and camshaft - removal, inspection and refitting 4 Removal 1 The camshaft can only be removed once the camshaft housing has been removed from the engine. Since the camshaft housing is secured in position by the cylinder head bolts, it is not possible to remove the camshaft without removing the cylinder head (see Section 12). Note: In theory it is possible to remove the camshaft housing once the cylinder head bolts have been removed, and leave the head in position. However, this procedure carries a high risk of disturbing the head gasket, resulting in the head gasket blowing once the camshaft and housing are refitted. If you wish to attempt this, proceed as described in Section 12, noting that it will not be necessary to remove the manifolds, etc. Be warned though that after refitting, you may find the head gasket will need renewing, meaning that the cylinder head will have to be removed after all. The decision is yours as to 10.3b . . . then remove the thrustplate . . . 3510 Vauxhall/Opel Omega Inspection 5 With the camshaft removed, examine the bearings in the camshaft housing for signs of obvious wear or pitting. If evident, a new camshaft housing will probably be required. Also check that the oil supply holes in the camshaft housing are free from obstructions. 6 The camshaft itself should show no marks or scoring on the journal or cam lobe surfaces. If evident, renew the camshaft. If the camshaft lobes show signs of wear also examine the followers (see Section 11). Check the camshaft thrustplate for signs of wear or grooves, and renew if necessary. Refitting 7 Carefully prise the old seal out of from the camshaft housing, using a suitable 10.4 . . . and slide the camshaft out from the housing 2A 2A•8 2.0 litre SOHC engine in-car repair procedures 11.8a Remove each follower . . . 11.8b . . . thrust pad . . . 11.8c . . . and hydraulic tappet from the cylinder head screwdriver. Ensure the housing is clean then press the in new seal, ensuring its sealing lip is facing inwards, until it is flush with the housing. 8 Liberally lubricate the camshaft and housing bearings and the oil seal lip with fresh engine oil. 9 Carefully insert the camshaft into the housing, taking care not to mark the bearing surfaces or damage the oil seal lip. 10 Slide the thrustplate into position, engaging it with the camshaft slot, and tighten its retaining bolts to the specified torque. Check the camshaft endfloat (see paragraph 3). 11 Ensure the mating surfaces are clean and dry and fit a new gasket to the rear of the housing. Refit the cover and tighten its retaining bolts to the specified torque. 12 Refit the camshaft housing as described in Section 12. 5 Lubricate the tappet and follower with fresh engine oil then slide the tappet into its bore in the cylinder head. Manoeuvre the follower into position, ensuring it is correctly engaged with the tappet and valve stem, then carefully remove the service tool. 6 Repeat the operation on the remaining followers and tappets then refit the spark plug(s) (see Chapter 1). follower bearing surface is badly scored, also examine the corresponding lobe on the camshaft for wear, as it is likely that both will be worn. Also check the thrust pad for signs of wear or damage. Renew worn components as necessary. 10 If the hydraulic tappets are thought to be faulty they should be renewed; testing of the tappets is not possible. Without special tool Refitting Removal 11 Lubricate the hydraulic tappets and their cylinder head bores with clean engine oil. Refit the tappets to the cylinder head, making sure they are fitted in their original locations. 12 Fit each thrust pad to the top of its respective valve. 13 Lubricate the followers with clean engine oil. Fit each follower, making sure it is correctly located with both the tappet and thrust pad, then refit the camshaft housing (see Section 10). 11 Camshaft followers and hydraulic tappets - removal, inspection and refitting 4 7 Without the use of the special tool, it will be necessary to remove the camshaft housing to allow the followers and tappets to be removed (see Section 10, paragraph 1). 8 With the housing removed, obtain eight small, clean plastic containers, and number them 1 to 8; alternatively, divide a larger container into eight compartments. Lift out each follower, thrust pad and hydraulic tappet in turn, and place them in their respective container (see illustrations). Do not interchange the cam followers, or the rate of wear will be much-increased. 12 Cylinder head removal and refitting Inspection Using Vauxhall service tool (tool no. KM-565) 1 If access to the special tool (KM-565) or a suitable equivalent can be gained, the cam followers and tappets can be removed as follows, without disturbing the camshaft. 2 Remove the camshaft cover as described in Section 4. 3 Using a socket and extension bar, rotate the crankshaft in the normal direction of rotation until the camshaft lobe of the first follower/ tappet to be removed is pointing straight upwards. Remove the spark plug from the corresponding cylinder (see Chapter 1). 4 Fit the service tool to the top of the camshaft housing, making sure the tool end is correctly engaged with the top of the valve. Screw the tool stud into one of the housing bolt holes until the valve is sufficiently depressed to allow the follower to be slid out from underneath the camshaft. The hydraulic tappet can then also be removed as can the thrust pad from the top of the valve. Inspect the components (see paragraphs 10 and 11) and renew if worn or damaged. 9 Examine the cam follower bearing surfaces which contact the camshaft lobes for wear ridges and scoring. Renew any follower on which these conditions are apparent. If a 12.3 Prior to removing the timing belt, rotate the crankshaft 60º backwards to ensure the camshaft and pistons are safely positioned 3510 Vauxhall/Opel Omega 4 Removal Note: The engine must be cold when removing the cylinder head. New cylinder head bolts must be used on refitting. 1 Disconnect the battery negative lead. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Drain the cooling system and remove the spark plugs and auxiliary drivebelt as described in Chapter 1. 3 Remove the timing belt as described in Section 7. Prior to releasing the timing belt tension and removing the belt, rotate the crankshaft backwards by approximately 60º (4 teeth of movement); this will position the camshaft so that the valve spring pressure is evenly exerted along its the complete length, preventing the shaft turning and reducing the risk of the valves contacting the pistons (see illustration). 2.0 litre SOHC engine in-car repair procedures 2A•9 4 Remove the inlet and exhaust manifolds as described in Chapter 4A. If no work is to be carried out on the cylinder head, the head can be removed complete with manifolds once the following operations have been carried out (see Chapters 4A and 4B). a) Remove the duct linking the air cleaner to the throttle housing. b) Disconnect the wiring connectors from the throttle potentiometer, idle speed adjuster, injectors, EGR valve, purge valve and oxygen sensor. Unbolt the earth connection from the fuel rail and release all wiring from the inlet manifold. c) Depressurise the fuel system then disconnect the fuel hoses from the fuel rail. d) Disconnect the various vacuum and coolant hoses from the inlet manifold/throttle housing. e) Unbolt the inlet manifold support bracket and the alternator upper bracket. f) Disconnect the accelerator cable. g) Unbolt the exhaust front pipe from the manifold and its mounting bracket. 5 Remove the camshaft cover as described in Section 4. 6 Remove the camshaft sprocket as described in Section 8. 7 Undo the retaining bolts securing the timing belt rear cover to the camshaft housing. 8 Disconnect the wiring connectors from the DIS module, the coolant temperature sensor, the knock sensor and the crankshaft sensor. Undo the bolt(s) securing the earth lead(s) to the front of the cylinder head then position the wiring cover assembly clear of the cylinder head. 9 Slacken the retaining clips and disconnect the coolant hoses from the thermostat housing on the front end of the cylinder head. Also disconnect the wiring connector from the coolant temperature gauge sender unit on the left-hand side of the thermostat housing. 10 Make a final check to ensure that all relevant hoses, pipes and wires, etc, have been disconnected. 11 Working in the reverse of the tightening sequence (see illustration 12.29), progressively slacken the cylinder head bolts by a quarter of a turn at a time until all bolts can be unscrewed by hand. Remove each bolt in turn, along with its washer. 12 Lift the camshaft housing from the cylinder head. If necessary, tap the housing gently with a soft-faced mallet to free it from the cylinder head, but do not lever at the mating faces. Note the fitted positions of the two locating dowels, and remove them for safe keeping if they are loose. 13 Lift the cylinder head from the cylinder block, taking care not to dislodge the cam followers or thrust pads. If necessary, tap the cylinder head gently with a soft-faced mallet to free it from the block, but do not lever at the mating faces. Note the fitted positions of the two locating dowels, and remove them for safe keeping if they are loose. 12.21 Fit the new gasket to the cylinder block, engaging it with the locating dowels (arrowed) . . . 12.22 . . . making sure its OBEN/TOP marking is uppermost 14 Recover the cylinder head gasket, and discard it. block, making sure it is fitted with the correct way up with its OBEN or TOP mark uppermost and at the front end of the engine (see illustration). 23 Carefully refit the cylinder head, locating it on the dowels. 24 Ensure the mating surfaces of the cylinder head and camshaft housing are clean and dry and that all the camshaft followers are correctly located with the tappets and thrust pad. 25 Apply a bead of suitable sealant (Vauxhall recommend the use of sealant 15 03 170 available from your Vauxhall dealer) to the cylinder head mating surface (see illustration). 26 Ensure the two locating dowels are in position then lubricate the camshaft followers with clean engine oil. 27 Carefully lower the camshaft housing assembly into position, locating it on the dowels. 28 Fit the washers to the new cylinder head bolts then carefully insert them into position (do not drop), tightening them finger-tight only at this stage. 29 Working progressively and in the sequence shown, first tighten all the cylinder head bolts to the stage 1 torque setting (see illustration). 30 Once all bolts have been tightened to the stage 1 torque, again working in the sequence shown, tighten each bolt through its specified stage 2 angle, using a socket and extension bar. Preparation for refitting 15 The mating faces of the cylinder head and block must be perfectly clean before refitting the head. Use a scraper to remove all traces of gasket and carbon, and also clean the tops of the pistons. Take particular care with the aluminium surfaces, as the soft metal is damaged easily. Also, make sure that debris is not allowed to enter the oil and water channels - this is particularly important for the oil circuit, as carbon could block the oil supply to the camshaft or crankshaft bearings. Using adhesive tape and paper, seal the water, oil and bolt holes in the cylinder block. To prevent carbon entering the gap between the pistons and bores, smear a little grease in the gap. After cleaning the piston, rotate the crankshaft so that the piston moves down the bore, then wipe out the grease and carbon with a cloth rag. Clean the piston crowns in the same way. 16 Check the block and head for nicks, deep scratches and other damage. If slight, they may be removed carefully with a file. More serious damage may be repaired by machining, but this is a specialist job. 17 If warpage of the cylinder head is suspected, use a straight-edge to check it for distortion. Refer to Chapter 2D if necessary. 18 Ensure that the cylinder head bolt holes in the crankcase are clean and free of oil. Syringe or soak up any oil left in the bolt holes. This is most important in order that the correct bolt tightening torque can be applied and to prevent the possibility of the block being cracked by hydraulic pressure when the bolts are tightened. 19 Renew the cylinder head bolts regardless of their apparent condition. Refitting 20 Ensure the crankshaft is till positioned approximately 60º BTDC and wipe clean the mating faces of the head and block. 21 Ensure that the two locating dowels are in position at each end of the cylinder block/crankcase surface (see illustration). 22 Fit the new cylinder head gasket to the 3510 Vauxhall/Opel Omega 12.25 Apply sealant to the cylinder head upper mating surface then refit the camshaft housing 2A 2A•10 2.0 litre SOHC engine in-car repair procedures 12.29 Cylinder head bolt tightening sequence It is recommended that an angle-measuring gauge is used during this stage of the tightening, to ensure accuracy (see illustration). 31 Working in the specified sequence, go around again and tighten all bolts through the specified stage 3 angle. 32 Finally go around in the specified sequence again and tighten all bolts through the specified stage 4 angle. 33 Refit the bolts securing the timing belt rear cover to the camshaft housing and tighten them to the specified torque. 34 Refit the camshaft sprocket as described in Section 8. 35 Align all the sprocket timing marks to bring the camshaft and crankshaft back to TDC (see Section 3) then refit the timing belt as described in Section 7. 36 Reconnect the wiring connectors to the cylinder head components, ensuring all wiring is correctly routed, and secure it in position with the necessary clips. 37 Reconnect the coolant hoses to the thermostat housings and securely tighten the retaining clips. 38 Refit/reconnect the manifolds as described in Chapter 4A. 39 Refit the undercover then lower the vehicle to the floor. 40 Ensure all pipes and hoses are securely reconnected then refill the cooling system and refit the spark plugs as described in Chapter 1. 41 Reconnect the battery then start the engine and check for signs of leaks. 13 Sump removal and refitting 3 Removal Note: A new baffle plate will be required on refitting (the sump gasket is an integral part of the plate). 12.30 Working in the specified sequence, tighten the cylinder head bolts to the specified stage 1 torque setting and then through the various specified angles (see text) 1 Disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Firmly apply the handbrake then jack up the front of the car and support it on axle stands. Undo the retaining screws and remove the undercover from beneath the engine. 3 Drain the engine oil as described in Chapter 1, then fit a new sealing washer and refit the drain plug, tightening it to the specified torque. 4 Where necessary, disconnect the wiring connector from the oil level sender unit on the sump. 5 Slacken and remove the bolts securing the support brackets to the transmission housing and sides of the cylinder block. Remove both brackets from the engine then remove the flywheel lower cover plate from the base of the transmission housing. 6 Slacken and remove the nuts securing the left- and right-hand engine mounting brackets to the top of the rubber mountings. Unbolt the right-hand mounting bracket and remove it from the cylinder block. 7 Attach an engine hoist to the cylinder head lifting brackets then raise the hoist until it is supporting the weight of the engine. 8 Progressively slacken and remove the bolts securing the sump to the base of the cylinder block/oil pump. Break the sump joint by striking the sump with the palm of the hand, then lower the sump away from the engine and withdraw it. Raise the engine unit slightly to gain the necessary clearance required for sump removal, taking care not to place any excess strain on the engine wiring/hoses or exhaust system. 9 Undo the retaining bolts and remove the oil pump pick-up/strainer from the base of the oil pump housing, noting the sealing ring, then remove the baffle plate assembly. 3510 Vauxhall/Opel Omega 10 Check the oil pump pick-up/strainer for signs of clogging or splitting and renew/clean as necessary. Note: If the sump is to be removed for any length of time, refit the mounting bracket to the cylinder block and lower the engine back down onto its mounting rubbers. Refitting 11 Remove all traces of dirt and oil from the mating surfaces of the sump, cylinder block and oil pump housing. Also remove all traces of locking compound from the threads of the oil pump pick-up/strainer bolts and the sump retaining bolts. 12 Apply a smear of suitable sealant (Vauxhall recommend the use of sealant 15 03 295 - available from your Vauxhall dealer) to the areas of the cylinder block mating surface around the areas of the oil pump housing and rear main bearing cap joints. 13 Fit a new sealing ring to the oil pump pickup/strainer and apply a few drops of locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of the strainer retaining bolts. 14 Offer up the new baffle plate, making sure it is correctly located, then refit the oil pump strainer tightening its retaining bolts to the specified torque. 15 Apply a drop of locking compound to each of the sump retaining bolts then offer up the sump to the cylinder block. Refit the retaining bolts and progressively tighten them to the specified torque, working out from the centre in a diagonal sequence. 16 Refit the mounting bracket to the cylinder block and tighten its retaining bolts to the specified torque. Lower the engine back down onto its mountings making sure the brackets and mounting rubbers are correctly aligned. Remove the hoist from the engine then refit the mounting nuts, tightening them to the specified torque setting. 2.0 litre SOHC engine in-car repair procedures 2A•11 14.8 Undo the retaining screws and remove the oil pump cover 14.10 Lift the inner and outer gears (arrowed) out from the pump housing 17 Refit the flywheel lower cover plate to the transmission housing then refit the support brackets. Screw in the bolts securing the brackets to the cylinder block and transmission housing and tighten them to their specified torque settings. 18 Reconnect the oil level sender wiring connector (where fitted). 19 Refit the undercover then lower the vehicle to the ground then fill the engine with fresh oil, with reference to Chapter 1. of the end of the crankshaft, taking great care not to lose the locating dowels. Remove the housing gasket and discard it. Overhaul 1 Drain the engine oil as described in Chapter 1, then fit a new sealing washer and refit the drain plug, tightening it to the specified torque. Remove the oil filter and discard it. 2 Remove the timing belt as described in Section 7. 3 Remove the camshaft and crankshaft timing belt sprockets and the tensioner as described in Section 8. 4 Unbolt the timing belt rear cover from the camshaft housing and oil pump and remove it from the engine. 5 Remove the sump and oil pump pickup/strainer as described in Section 13. 6 Disconnect the wiring connector from the oil pressure switch. 7 Slacken and remove the retaining bolts then slide the oil pump housing assembly off 8 Undo the retaining screws and lift off the pump cover from the rear of the housing (see illustration). 9 Using a suitable marker pen, mark the surface of both the pump inner and outer gears; the marks can then be used to ensure the rotors are refitted the correct way around. 10 Lift out the inner and outer gears from the pump housing (see illustration). 11 Unscrew the oil pressure relief valve bolt from the side of the housing and withdraw the spring and plunger from the housing, noting which way around the plunger is fitted (see illustration). Remove the sealing washer from the valve bolt. Note: The pressure relief valve can be removed with pump in position on the engine unit. 12 Clean the components, and carefully examine the gears, pump body and relief valve plunger for any signs of scoring or wear. Renew any component which shows signs of wear or damage; if the gears or pump housing are marked then the complete pump assembly should be renewed. 13 If the components appear serviceable, measure the clearance between the inner gear to outer gear clearance using feeler blades. Also measure the gear endfloat, and check the flatness of the end cover (see illustrations). If the clearances exceed the specified tolerances, the pump must be renewed. 14.13a Using a feeler blade to check gear clearance 14.13b Using a straight edge and feeler blade to measure gear endfloat 14 Oil pump removal, overhaul and refitting 4 Removal 3510 Vauxhall/Opel Omega 14.11 Oil pressure relief valve components 1 Plunger 2 Spring 3 Sealing washer 4 Valve bolt 14 If the pump is satisfactory, reassemble the components in the reverse order of removal, noting the following. a) Ensure both gears are fitted the correct way around. b) Fit a new sealing washer to the pressure relief valve bolt and tighten the bolt to the specified torque. c) Remove all traces of locking compound from the cover screws. Apply a drop of fresh locking compound to each screw and tighten the screws to the specified torque. d) On completion prime the oil pump by filling it with clean engine oil whilst rotating the inner gear. Refitting 15 Prior to refitting, carefully lever out the crankshaft oil seal using a flat-bladed screwdriver. Fit the new oil seal, ensuring its sealing lip is facing inwards, and press it squarely into the housing using a tubular drift which bears only on the hard outer edge of the seal (see illustration). Press the seal into position so that it is flush with the housing and lubricate the oil seal lip with clean engine oil. 16 Ensure the mating surfaces of the oil pump and cylinder block are clean and dry and the locating dowels are in position. 17 Fit a new gasket to the cylinder block. 18 Carefully manoeuvre the oil pump into position and engage the inner gear with the crankshaft end. Locate the pump on the dowels, taking great care not to damage the oil seal lip. 14.15 Fitting a new crankshaft oil seal to the oil pump housing 2A 2A•12 2.0 litre SOHC engine in-car repair procedures 15.2 Lock the flywheel/driveplate ring gear with a tool similar to that shown 19 Refit the pump housing retaining bolts in their original locations and tighten them to the specified torque. 20 Reconnect the oil pressure sensor wiring connector. 21 Refit the oil pump pick-up/strainer and sump as described in Section 13. 22 Refit the rear timing belt cover to the engine, tightening its retaining bolts to the specified torque. 23 Refit the timing belt sprockets and tensioner then refit the belt as described in Sections 7 and 8. 24 On completion fit a new oil filter and fill the engine with clean oil as described in Chapter 1. 15 Flywheel/driveplate removal, inspection and refitting 4 Note: New flywheel/driveplate retaining bolts will be required on refitting. Removal Manual transmission models 1 Remove the transmission as described in Chapter 7A then remove the clutch assembly as described in Chapter 6. 2 Prevent the flywheel from turning by locking the ring gear teeth with a similar arrangement to that shown (see illustration). Alternatively, bolt a strap between the flywheel and the cylinder block/crankcase. Make alignment marks between the flywheel and crankshaft using paint or a suitable marker pen. 3 Slacken and remove the retaining bolts and remove the flywheel. Do not drop it, as it is very heavy. Automatic transmission models 4 Remove the transmission as described in Chapter 7B. 5 Lock the driveplate as described in paragraph 2 then slacken the driveplate retaining bolts. 6 Unscrew the retaining bolts and remove the retaining plate, centering ring and driveplate from the end of the crankshaft, noting each components correct fitted location. 15.12a On manual transmission models, tighten the flywheel bolts to the specified stage 1 torque setting . . . 15.12b . . . then tighten them through the specified stage 2 and 3 angles Inspection Automatic transmission models 7 On manual transmission models, examine the flywheel for scoring of the clutch face. If the clutch face is scored, the flywheel may be surface-ground, but renewal is preferable. Check for wear or chipping of the ring gear teeth. Renewal of the ring gear is possible on models with a normal flywheel but is not a task for the home mechanic; renewal requires the new ring gear to be heated (up to 180º to 230ºC) to allow it to be fitted. On dual-mass flywheels ring gear renewal is not possible. 8 On automatic transmission models closely examine the driveplate for ring gear teeth for signs of wear or damage and check the driveplate surface for any signs of cracks. 9 If there is any doubt about the condition of the flywheel/driveplate, seek the advice of a Vauxhall dealer or engine reconditioning specialist. They will be able to advise if it is possible to recondition it or whether renewal is necessary. 14 Clean the mating surfaces of the driveplate and crankshaft and remove all traces of locking compound from the driveplate retaining bolt threads in the crankshaft. 15 Offer up the driveplate complete with the centering ring and retaining plate, making sure all components are fitted the correct way around, then screw in the new retaining bolts. 16 Tighten the retaining bolts through the specified torque and angles as described in paragraph 12 then remove the locking tool and refit the transmission as described in Chapter 7B. Refitting Manual transmission models 10 Clean the mating surfaces of the flywheel and crankshaft and remove all traces of locking compound from the flywheel retaining bolt threads in the crankshaft. 11 Offer up the flywheel and fit the new retaining bolts. If the original is being refitted align the marks made prior to removal. 12 Lock the flywheel by the method used on removal, and tighten the retaining bolts to the specified stage 1 torque setting then angletighten the bolts through the specified stage 2 angle, using a socket and extension bar, and finally through the specified stage 3 angle. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy (see illustrations). If a gauge is not available, use white paint to make alignment marks between the bolt head and flywheel prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 13 Refit the clutch as described in Chapter 6 then remove the locking tool, and refit the transmission as described in Chapter 7A. 3510 Vauxhall/Opel Omega 16 Crankshaft oil seals renewal 4 Front (timing belt end) oil seal 1 Remove the crankshaft sprocket as described in Section 8. 2 Carefully punch or drill two small holes opposite each other in the oil seal. Screw a self-tapping screw into each and pull on the screws with pliers to extract the seal (see illustration). Alternatively carefully lever the seal out of position. Caution: Great care must be taken to avoid damage to the oil pump 3 Clean the seal housing and polish off any burrs or raised edges which may have caused the seal to fail in the first place. 16.2 Removing the crankshaft front oil seal 2.0 litre SOHC engine in-car repair procedures 2A•13 16.4 Fitting a new crankshaft front oil seal 4 Lubricate the lips of the new seal with clean engine oil and ease it into position on the end of the shaft. Press the seal squarely into position until it is flush with the housing. If necessary, a suitable tubular drift, such as a socket, which bears only on the hard outer edge of the seal can be used to tap the seal into position (see illustration). Take great care not to damage the seal lips during fitting and ensure that the seal lips face inwards. 5 Wash off any traces of oil, then refit the crankshaft sprocket as described in Section 8. Rear (flywheel/driveplate end) oil seal 6 Remove the flywheel/driveplate as described in Section 15. 7 Renew the seal as described in paragraphs 2 to 4. 8 Refit the flywheel/driveplate as described in Section 15. 17 Engine/transmission mountings inspection and renewal 3 Inspection 1 If improved access is required, raise the front of the car and support it securely on axle stands. Undo the retaining bolts and remove the undercover from beneath the engine unit. 2 Check the mounting rubber to see if it is cracked, hardened or separated from the metal at any point; renew the mounting if any such damage or deterioration is evident. 3 Check that all the mounting’s fasteners are securely tightened; use a torque wrench to check if possible. 4 Using a large screwdriver or a pry bar, check for wear in the mounting by carefully levering against it to check for free play; where this is not possible, enlist the aid of an assistant to move the engine/transmission unit back and forth, or from side to side, while you watch the mounting. While some free play is to be expected even from new components, excessive wear should be obvious. If excessive free play is found, check first that the fasteners are correctly secured, then renew any worn components as described below. Renewal Left- and right-hand engine mountings Note: It is recommended that the engine mountings are replaced as a matched pair. 5 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Undo the retaining screws and remove the undercover from beneath the engine. 6 Support the weight of the engine/ transmission using a trolley jack with a block of wood placed on its head. Alternatively attach an engine hoist to the lifting brackets on the cylinder head and use the hoist to support the engine. 7 Unscrew the upper and lower nuts securing the relevant engine mounting to the cylinder block bracket and subframe then raise the engine unit slightly and manoeuvre the mounting out of position. If necessary the mounting bracket can be unbolted and removed from the cylinder block. Note: Take great care not to place any excess stress on any engine wiring/hoses or the exhaust system or when raising the engine. 8 Check all components for signs of wear or damage, and renew as necessary. 9 On refitting, refit the mounting to the 3510 Vauxhall/Opel Omega subframe aligning its locating lug with the subframe slot then refit the lower nut and tighten to the specified torque. 10 Refit the mounting bracket (where removed) to the cylinder block and tighten its retaining bolts to the specified torque. 11 Lower the engine unit back down onto the mounting, making sure it is correctly located, then remove the jack/hoist (as applicable). Fit the upper retaining nut to the mounting and tighten it to the specified torque. 12 Refit the undercover then lower the vehicle to the ground. Transmission unit rear mounting 13 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 14 Place a jack with a block of wood beneath the transmission, and raise the jack to take the weight of the transmission. 15 With the transmission securely supported, slacken and remove the bolts securing the transmission unit rear mounting crossmember to the vehicle body. Unscrew the nuts securing the crossmember to the mounting and remove it from the vehicle. 16 Slacken and remove the bolts and remove the mounting from the base of the transmission unit. 17 Check all components for signs of wear or damage, and renew as necessary. Remove all traces of locking compound from the crossmember to body bolt threads. 18 Fit the mounting to the transmission unit and tighten its retaining bolts to the specified torque. 19 Refit the crossmember to the mounting and lightly tighten its retaining nuts. 20 Apply a few drops of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of each crossmember to body bolt then refit both bolts and tighten them to the specified torque. 21 Remove the jack from underneath the transmission unit then tighten the mounting to crossmember nuts to the specified torque before lowering the vehicle to the ground. 2A 2B•1 Chapter 2 Part B: 2.0 litre DOHC engine in-car repair procedures Contents Camshafts and followers - removal, inspection and refitting . . . . . . 10 Camshaft cover - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 4 Camshaft oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Compression test - description and interpretation . . . . . . . . . . . . . . 2 Crankshaft balancer unit (1998 model year onwards) - removal, refitting and adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Crankshaft oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Crankshaft pulley - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 5 Cylinder head - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 11 Engine oil and filter - renewal . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Engine oil level check . . . . . . . . . . . . . . . . . . . . . . .See Weekly checks Engine/transmission mountings - inspection and renewal . . . . . . . . 17 Flywheel/driveplate - removal, inspection and refitting . . . . . . . . . . . 15 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Oil pump - removal, overhaul and refitting . . . . . . . . . . . . . . . . . . . . 13 Sump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Timing belt - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Timing belt covers - removal and refitting . . . . . . . . . . . . . . . . . . . . . 6 Timing belt sprockets, tensioner and idler pulleys - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Top dead centre (TDC) for No 1 piston - locating . . . . . . . . . . . . . . . 3 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications General Engine type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manufacturer’s engine code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direction of crankshaft rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compression ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Four-cylinder, in-line, water-cooled. Double overhead camshaft, beltdriven X20XEV 86.0 mm 86.0 mm 1998 cc 1-3-4-2 (No 1 cylinder at timing belt end) Clockwise (viewed from timing belt end of engine) 10.8:1 100 kW at 5600 rpm 185 Nm at 4000 rpm Compression pressures Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum difference between any two cylinders . . . . . . . . . . . . . . . . . . 12 to 15 bar (174 to 218 psi) 1 bar (15 psi) Camshaft Cam lift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 mm Lubrication system Oil pump type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Minimum permissible oil pressure at idle speed, with engine at operating temperature (oil temperature of at least 80°C) . . . . . . . . Oil pump clearances: Gear teeth clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear-type, driven directly from crankshaft 1.5 bar (22 psi) 0.08 to 0.15 mm 0.03 to 0.10 mm 3510 Vauxhall/Opel Omega 2B 2B•2 2.0 litre DOHC engine in-car repair procedures Torque wrench settings Nm Camshaft bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Camshaft cover bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Camshaft sprocket bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 60° Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 15° Coolant pump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Connecting rod big-end bearing cap bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 45° Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 15° Crankcase breather tube bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Crankshaft balancer unit bolts - 1998-on engines: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 45° Crankshaft pulley bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Crankshaft sensor rotor bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Crankshaft sprocket bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 40 to 50° Cylinder head bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 90° Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 90° Stage 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 90° Stage 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 15° Driveplate bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 30° Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 15° Engine/transmission mounting bolts: Left- and right-hand mountings: Mounting-to-subframe nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Mounting-to-mounting bracket nut . . . . . . . . . . . . . . . . . . . . . . . . . 40 Mounting bracket-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . 60 Rear mounting: Mounting-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Mounting-to-crossmember nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Crossmember-to-body bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Engine-to-transmission unit bolts: Transmission-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . . . . . . 60 Transmission-to-sump flange bolts (engines with a two-piece sump) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Engine-to-transmission support bracket bolts - engines with one-piece sump: Bracket-to-engine bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Bracket-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Flywheel bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 30° Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 15° Main bearing cap bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 45° Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 15° Main bearing cap bridge casting/baffle plate bolts - engines with two piece sump: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 45° Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Oil pump: Retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Pump cover screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Oil pressure relief valve bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Oil pump pick-up/strainer bolts: Engines with one-piece sump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3510 Vauxhall/Opel Omega lbf ft 6 6 37 18 26 18 15 15 10 96 18 41 41 30 44 30 15 33 44 30 30 16 48 37 15 11 6 4 37 6 2.0 litre DOHC engine in-car repair procedures 2B•3 Torque wrench settings (continued) Oil pump pick-up/strainer bolts (continued): Engines with two piece sump: Pick-up-to-oil pump housing bolts . . . . . . . . . . . . . . . . . . . . . . . . . Pick-up-to-casting/balancer unit bolts: M6 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M8 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sump bolts: One-piece sump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Two-piece sump: Sump pan bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main casting bolts: Casting-to-cylinder block/oil pump bolts . . . . . . . . . . . . . . . . . . Casting flange-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . Sump drain plug: Hex-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torx-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt cover bolts: Outer cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt idler pulley: Pulley bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mounting bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt tensioner bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 General information How to use this Chapter 1 This Part of Chapter 2 is devoted to in-car repair procedures for the engine. All procedures concerning engine removal and refitting, and engine block/cylinder head overhaul can be found in Chapter 2D. 2 Most of the operations included in this Part are based on the assumption that the engine is still installed in the car. Therefore, if this information is being used during a complete engine overhaul, with the engine already removed, many of the steps included here will not apply. Engine description 3 The engine is a double overhead camshaft, four-cylinder, in-line unit, mounted at the front of the car with the transmission on its rear. This engine is often referred to as the 2.0 litre ECOTEC engine (Emission Consumption Optimized TEChnology). 4 The cylinder block is of the dry-liner type. The crankshaft is supported within the cylinder block on five shell-type main bearings. Thrustwashers are fitted to number 3 main bearing, to control crankshaft endfloat. 5 The connecting rods are attached to the crankshaft by horizontally split shell-type bigend bearings, and to the pistons by interference-fit gudgeon pins. The aluminium alloy pistons are of the slipper type, and are fitted with three piston rings, comprising two Nm lbf ft 8 6 10 20 7 15 15 11 8 Angle-tighten a further 30° 6 20 40 15 30 45 10 33 7 6 8 4 6 25 25 20 18 18 15 compression rings and a scraper-type oil control ring. 6 The camshafts run directly in the cylinder head, and are driven by the crankshaft via a toothed rubber timing belt (which also drives the coolant pump). The camshafts operate each valve via a follower. Each follower incorporates a hydraulic self-adjusting valve which automatically adjust the valve clearances. 7 Lubrication is by pressure-feed from a gear-type oil pump, which is mounted on the front end of the crankshaft. It draws oil through a strainer located in the sump, and then forces it through an externally mounted full-flow cartridge-type filter. The oil flows into galleries in the main bearing cap bridge arrangement and cylinder block/crankcase, from where it is distributed to the crankshaft (main bearings) and camshafts. The big-end bearings are supplied with oil via internal drillings in the crankshaft, while the camshaft bearings also receive a pressurised supply. The camshaft lobes and valves are lubricated by splash, as are all other engine components. 8 On later (1998 model year onwards) engines, a crankshaft balancer unit is fitted to the engine to smooth out the forces which occur during normal crankshaft/piston movement. The balancer unit houses two balance shafts and is bolted onto the base of the cylinder block, directly beneath number 2 cylinder. The balancer shaft gears are meshed together and the gear of the first shaft is driven by the crankshaft via a gear which forms the third web of the crankshaft. The crankshaft gear has twice as many teeth as 3510 Vauxhall/Opel Omega the balance shaft gears and so drives the balance shaft at twice the speed of the crankshaft, the first balance shaft rotates in the opposite direction to the crankshaft and the second in the same direction. 9 A semi-closed crankcase ventilation system is employed; crankcase fumes are drawn from cylinder head cover, and passed via a hose to the inlet manifold. Repair operations possible with the engine in the car 10 The following operations can be carried out without having to remove the engine from the vehicle. a) Removal and refitting of the cylinder head. b) Removal and refitting of the timing belt and sprockets. c) Renewal of the camshaft oil seals. d) Removal and refitting of the camshafts and followers. e) Removal and refitting of the sump. f) Removal and refitting of the connecting rods and pistons*. g) Removal and refitting of the oil pump. h) Renewal of the crankshaft balancer unit 1998 on engines. i) Renewal of the crankshaft oil seals. j) Renewal of the engine mountings. k) Removal and refitting of the flywheel/driveplate. * Although the operation marked with an asterisk can be carried out with the engine in the car after removal of the sump, it is better for the engine to be removed, in the interests of cleanliness and improved access. For this reason, the procedure is described in Chapter 2D. 2B 2B•4 2.0 litre DOHC engine in-car repair procedures 3.5 Align the camshaft sprocket timing marks with the cutout on the camshaft cover (1) and align the crankshaft pulley notch with the pointer (2) to position No 1 piston at TDC on its compression stroke 2 Compression test description and interpretation 4 Camshaft cover removal and refitting 2 Removal Refer to Chapter 2A, Section 2. 3 Top dead centre (TDC) for No 1 piston locating 4 To gain access to the camshaft sprocket timing marks, remove the timing belt outer cover as described in Section 6. 5 Using a socket and extension bar on the crankshaft sprocket bolt, rotate the crankshaft until the timing marks on the camshaft sprockets are both at the top and are correctly aligned with the marks on the camshaft cover. With the camshaft sprocket marks correctly positioned, align the notch on the crankshaft pulley rim with the pointer (see illustration). The engine is now positioned with No1 piston at TDC on its compression stroke. Note: If the crankshaft pulley has been removed, use the mark on the crankshaft sprocket rim. The mark should be aligned with the cutout on the oil pump housing (see Section 7). 2 1 In its travel up and down its cylinder bore, Top Dead Centre (TDC) is the highest point that each piston reaches as the crankshaft rotates. While each piston reaches TDC both at the top of the compression stroke and again at the top of the exhaust stroke, for the purpose of timing the engine, TDC refers to the piston position (usually number 1) at the top of its compression stroke. 2 Number 1 piston (and cylinder) is at the front (timing belt) end of the engine, and its TDC position is located as follows. Note that the crankshaft rotates clockwise when viewed from the front of the vehicle. 3 Disconnect the battery negative terminal. If necessary, remove all the spark plugs as described in Chapter 1 to enable the engine to be easily turned over. 4.1 Release the retaining clips and disconnect the breather hoses from the camshaft cover 1 Slacken the retaining clips and disconnect the breather hoses from the camshaft cover (see illustration). 2 Undo the retaining screws and remove the spark plug cover. Disconnect the plug caps from the plugs then unclip the HT leads and position them clear of the cover (see illustrations). 3 Slacken the nut securing the engine wiring harness tray to the timing belt cover upper fixing then free the tray from the front of the cover and position it clear 4 Disconnect the camshaft sensor wiring connector and unclip the wiring from the camshaft cover. 5 Evenly and progressively slacken and remove the camshaft cover retaining bolts. 6 Lift the camshaft cover away from the cylinder head and recover the cover seal and the sealing rings which are fitted to each of the retaining bolt holes. Examine the seal and sealing rings for signs of wear or damage and renew if necessary. Refitting 7 Ensure the cover and cylinder head 4.2a Remove the spark plug cover . . . 3510 Vauxhall/Opel Omega surfaces are clean and dry then fit the camshaft seals securely to the cover grooves. Fit the sealing rings to the recesses around each retaining bolt hole, holding them in position with a smear of grease. 8 Apply a smear of suitable sealant (Vauxhall recommend the use of sealant 15 03 295 available from your Vauxhall dealer) to the areas of the cylinder head surface around the front inlet and exhaust camshaft bearing caps and also to the semi-circular cutouts on the rear of the head. 9 Carefully manoeuvre the camshaft cover into position, taking great care to ensure all the sealing rings remain correctly seated. Refit the cover retaining bolts and tighten the retaining bolts to the specified torque, working in a spiral pattern from the centre outwards. 10 Reconnect the breather hoses, securing them in position with the retaining clips, and securely reconnect the plug caps to the spark plugs. 11 Reconnect the camshaft sensor wiring connector then refit the spark plug cover and securely tighten its retaining screws. Clip the wiring tray back into position and securely tighten its retaining nut. 5 Crankshaft pulley removal and refitting 2 Removal 1 Remove the auxiliary drivebelt as described in Chapter 1. Prior to removal, mark the direction of rotation on the belt to ensure the belt is refitted the same way around. 2 Using a socket and extension bar on the crankshaft sprocket bolt, turn the crankshaft until the notch on the pulley rim is correctly aligned with the pointer on the cover (see illustration). 3 Slacken and remove the small retaining bolts securing the pulley to the crankshaft sprocket and remove the pulley from the engine. If necessary, prevent crankshaft rotation by holding the sprocket retaining bolt with a suitable socket. 4.2b . . . and disconnect the plug caps from the spark plugs 2.0 litre DOHC engine in-car repair procedures 2B•5 into position. Align the notch on the pulley rim with the pointer then seat the pulley on the sprocket and tighten its retaining bolts to the specified torque. 5 Refit the auxiliary drivebelt as described in Chapter 1 using the mark made prior to removal to ensure the belt is fitted the correct way around. 6 Timing belt covers removal and refitting 3 5.2 Align the crankshaft pulley notch with the pointer on the cover (arrowed - shown with timing belt outer cover removed) Outer cover Refitting Removal 4 Check that the crankshaft sprocket mark is still aligned with the mark on the oil pump housing then manoeuvre the crankshaft pulley 1 Remove the auxiliary drivebelt as described in Chapter 1. Prior to removal, mark the direction of rotation on the belt to ensure the belt is refitted the same way around. 2 Slacken and remove the nut securing the engine wiring harness tray to the outer cover upper mounting and free the tray assembly from the timing belt cover. Unclip the cover from the tray then free the wiring harness and coolant hose and remove the tray from the engine compartment (see illustrations). 3 Slacken and remove the retaining bolts, along with their washers and outer rubber spacers, then remove the outer cover from the engine unit along with its seal. Once the cover has been removed, recover inner rubber spacers from the mountings (see illustrations). 6.2a Undo the retaining nut and free the wiring tray from the outer cover . . . Refitting 4 Ensure the inner rubber spacers are correctly fitted to each of the mountings then manoeuvre the cover into position (see illustration). 5 Fit the washers and outer rubber spacers to the mounting bolts then refit the bolts in their original locations and tighten them to the specified torque (see illustration). 6 Seat the wiring harness correctly in the tray then refit the tray cover. Clip the tray securely onto the timing belt cover and securely tighten its retaining nut. 7 Refit the auxiliary drivebelt as described in Chapter 1 using the mark made prior to removal to ensure the belt is fitted the correct way around. Rear cover Removal 8 Remove the timing belt as described in Section 7. 9 Remove the camshaft sprockets, crankshaft sprocket, the timing belt tensioner and the idler pulley assembly as described in Section 8. 10 Unbolt the camshaft sensor from the cylinder head. 11 Undo the retaining bolts, noting their correct fitted locations, and remove the rear cover from the engine unit. Refitting 12 Refitting is the reverse of removal, tightening all bolts to the specified torque. 2B 6.2b . . . then unclip the cover . . . 6.2c . . . and free the wiring and coolant hose and remove the tray from the engine compartment 6.3a Slacken and remove the cover retaining bolts (upper bolt shown) and recover the outer rubber spacers . . . 6.3b . . . then remove the outer cover from the engine 6.4 Ensure the inner rubber spacers are correctly fitted to the mountings before installing the outer cover . . . 6.5 . . . and ensure the outer spacers are correctly positioned before refitting the retaining bolts 3510 Vauxhall/Opel Omega 2B•6 2.0 litre DOHC engine in-car repair procedures 7 Timing belt removal and refitting 3 Note: The timing belt must be removed and refitted with the engine cold. Removal 1 Disconnect the battery negative terminal then position No1 cylinder at TDC on its compression stroke as described in Section 3. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Remove the crankshaft pulley as described in Section 5. 3 Check the camshaft sprocket timing marks are correctly aligned with the camshaft cover marks and the crankshaft sprocket timing mark is aligned with the cutout on the oil pump housing. 4 Slacken the timing belt tensioner bolt (see illustration). Using an Allen key, rotate the tensioner arm clockwise to its stop, to relieve the tension in the timing belt, and hold it in position by and securely tighten the retaining bolt. 5 Slide the timing belt off from its sprockets and remove it from the engine. If the belt is to be re-used, use white paint or similar to mark the direction of rotation on the belt. Do not rotate the crankshaft or camshafts until the timing belt has been refitted. 6 Check the timing belt carefully for any signs of uneven wear, splitting or oil contamination, and renew it if there is the slightest doubt about its condition. If the engine is undergoing an overhaul and has covered 40 000 miles or it was more than 4 years since the original belt was fitted, renew the belt as a matter of course, regardless of its apparent condition (from 1997 onwards the belt renewal interval was increased to 80 000 miles or 8 years). If signs of oil contamination are found, trace the source of the oil leak and rectify it, then wash down the engine timing belt area and all related components to remove all traces of oil. 7.8 Align the camshaft sprocket marks (1) with the marks on the bearing caps (2) or cover and ensure the crankshaft sprocket timing mark is correctly aligned with the oil pump cutout (3) 3510 Vauxhall/Opel Omega 7.4 Slacken the timing belt tensioner bolt (1) and rotate the tensioner clockwise using an Allen key in the arm cutout (2) Refitting 7 On reassembly, thoroughly clean the timing belt sprockets and tensioner/idler pulleys. 8 Check that the crankshaft sprocket timing mark is still aligned with the cutout on the oil pump housing and the camshaft sprocket marks are aligned with the marks on the camshaft cover. If the camshaft cover has been removed, align the sprocket marks with the lugs on the top of the camshaft front bearing caps (see illustration). 9 Fit the timing belt over the crankshaft and camshaft sprockets and around the idler pulleys, ensuring that the belt left-hand run is taut (ie, all slack is on the tensioner side of the belt), then fit the belt over the coolant pump sprocket and tensioner pulley. Do not twist the belt sharply while refitting it. Ensure that the belt teeth are correctly seated centrally in the sprockets, and that the timing marks remain in alignment. If a used belt is being refitted, ensure that the arrow mark made on removal points in the normal direction of rotation, as before. 10 Slacken the timing belt tensioner bolt to release the tensioner spring. Rotate the tensioner arm anti-clockwise until the tensioner pointer is fully over against its stop, without exerting any excess strain on the belt (see illustration). Hold the tensioner in position and securely tighten its retaining bolt. 7.10 Tension the belt by rotating the tensioner arm fully anti-clockwise until the pointer is positioned as shown 2.0 litre DOHC engine in-car repair procedures 2B•7 11 Check the sprocket timing marks are still correctly aligned. If adjustment is necessary, release the tensioner again then disengage the belt from the sprockets and make any necessary adjustments. 12 Using a socket on the crankshaft sprocket bolt, rotate the crankshaft smoothly through two complete turns (720°) in the normal direction of rotation to settle the timing belt in position. 13 Check that both the camshaft and crankshaft sprocket timing marks are correctly realigned then slacken the tensioner bolt again. 14 If a new timing belt is being fitted, adjust the tensioner so that the pointer is aligned with either the cutout or NEW marking (depending on type of tensioner fitted) on the backplate (see illustration). Hold the tensioner in the correct position and tighten its retaining bolt to the specified torque. Rotate the crankshaft smoothly through another two complete turns in the normal direction of rotation, to bring the sprocket timing marks back into alignment. Check that the tensioner pointer is still aligned with the backplate cutout/marking (as applicable). 15 If the original belt is being refitted, adjust the tensioner so that the pointer is either positioned 4 mm to the left of the cutout or is aligned with the USED marking (depending on the type of tensioner fitted) on the backplate (see illustration 7.14). Hold the tensioner in the correct position and tighten its retaining bolt to the specified torque. Rotate the crankshaft smoothly through another two complete turns in the normal direction of rotation, to bring the sprocket timing marks back into alignment. Check that the tensioner pointer is still correctly positioned in relation to the backplate cutout/marking (as applicable). 16 If the tensioner pointer is not correctly positioned in relation to the backplate, repeat the procedure in paragraph 14 (new belt) or 15 (original belt) (as applicable). 17 Once the tensioner pointer and backplate remain correctly aligned, refit the timing belt cover and crankshaft pulley as described in Sections 5 and 6. 8 Timing belt sprockets, tensioner and idler pulleys removal and refitting 3 7.14 Ensure the timing belt tensioner arm (1) is correctly position in relation to the backplate cutout/marking (2) as described in text A Correct position for new belt - engines with an unmarked tensioner B Correct position for new belt - engines with a marked tensioner short), and three nuts and bolts; one nut and bolt forms the pivot of a forked tool, with the remaining two nuts and bolts at the tips of the ‘forks’ to engage with the sprocket spokes (see illustration 8.2 in Chapter 2A). b) Remove the camshaft cover as described in Section 4 and hold the camshaft with an open-ended spanner on the flats provided (see illustration). 3 Unscrew the retaining bolt and washer and remove the sprocket from the end of the camshaft. If the sprocket locating pin is a loose fit in the camshaft end, remove it and store it with the sprocket for safe-keeping. 4 If necessary, remove the remaining sprocket using the same method. C Correct position for used belt - engines with an unmarked tensioner D Correct position for used belt - engines with a marked tensioner Refitting 5 Prior to refitting check the oil seal(s) for signs of damage or leakage. If necessary, renew as described in Section 9. 6 Ensure the locating pin is in position in the camshaft end. 7 Note that both inlet and exhaust camshaft sprockets are the same but each one is equipped with two locating pin cutouts. If the sprocket is being fitted to the inlet camshaft engage the locating pin in the IN cutout, and if the sprocket is being fitted to the exhaust camshaft engage the locating pin in the EX (see illustration). 8 Ensure the camshaft locating pin is Camshaft sprockets Note: New sprocket retaining bolt(s) will be required on refitting. Removal 1 Remove the timing belt as described in Section 7. 2 The camshaft must be prevented from turning as the sprocket bolt is unscrewed, and this can be achieved in one of two ways. a) Make up a sprocket-holding tool using two lengths of steel strip (one long, the other 8.2 Using an open-ended spanner to retain the camshaft sprocket whilst the sprocket bolt is slackened 3510 Vauxhall/Opel Omega 8.7 Ensure the locating pin is engaged in the correct sprocket hole on refitting (see text) 2B 2B•8 2.0 litre DOHC engine in-car repair procedures engaged in the correct sprocket cutout then fit the washer and new retaining bolt. 9 Retain the sprocket by the method used on removal, and tighten the sprocket retaining bolt to the specified stage 1 torque setting then angle-tighten the bolt through the specified stage 2 angle, using a socket and extension bar, and finally through the specified stage 3 angle. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy. If a gauge is not available, use white paint to make alignment marks between the bolt head and sprocket prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 10 Refit the timing belt as described in Section 7 then (where necessary) refit the camshaft cover as described in Section 4. Crankshaft sprocket Note: A new crankshaft sprocket retaining bolt will be required on refitting. Removal 11 Remove the timing belt as described in Section 7. 12 The crankshaft must be prevented from turning as the sprocket bolt is unscrewed (the bolt is very tight), and this can be achieved in anyone of the following ways. a) Use the holding tool described in paragraph 2 securing the tool to the sprocket with two bolts screwed into opposite pulley retaining bolt holes. b) On manual transmission models have an assistant select top gear and apply the brakes firmly. c) If the engine is removed from the vehicle or the transmission unit has been removed the flywheel/driveplate can be locked (see Chapter 2A, Section 15). 13 Unscrew the retaining bolt and washer and remove the crankshaft sprocket from the end of the crankshaft. Discard the bolt; a new one must be used on refitting. If necessary, remove the sprocket Woodruff key from the crankshaft end and slide off the spacer. Refitting 14 Slide the spacer (where removed) onto the crankshaft then refit the Woodruff key to the crankshaft slot. 15 Align the sprocket with the key and slide it into position, ensuring the sprocket flange is facing outwards. Fit the washer and new retaining bolt. 16 Lock the crankshaft by the method used on removal, and tighten the sprocket retaining bolt to the specified stage 1 torque setting then angle-tighten the bolt through the specified stage 2 angle, using a socket and extension bar. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy. If a gauge is not available, use white paint to make alignment marks between the bolt head and sprocket prior to tightening; the marks can then be used to check that the bolt Refitting 24 Refit the pulley mounting bracket (where removed) to the cylinder block and tighten its retaining bolts to the specified torque. 25 Refit the idler pulley(s) and tighten the retaining bolt(s) to the specified torque. 26 Refit the timing belt as described in Section 7. 9 Camshaft oil seals renewal 10.1 Prior to removing the timing belt, rotate the crankshaft 60º backwards to ensure the camshaft and pistons are safely positioned has been rotated through the correct angle. 17 Refit the timing belt as described in Section 7. Tensioner assembly Removal 18 Remove the timing belt as described in Section 7. 19 Slacken and remove the retaining bolt and remove the tensioner assembly from the engine. Refitting 20 Fit the tensioner to the engine, making sure that the lug on the backplate is correctly located in the oil pump housing hole. Ensure the tensioner is correctly seated then refit the retaining bolt. Using an Allen key, rotate the tensioner arm clockwise to its stop then securely tighten the retaining bolt. 21 Refit the timing belt as described in Section 7. Idler pulleys Removal 22 Remove the timing belt as described in Section 7. 23 Slacken and remove the retaining bolt(s) and remove the idler pulley(s) from the engine. If necessary, unbolt the pulley mounting bracket and remove it from the cylinder block. 10.3 Removing a camshaft bearing cap 3510 Vauxhall/Opel Omega 3 1 Remove the relevant camshaft sprocket as described in Section 8. 2 Carefully punch or drill two small holes opposite each other in the oil seal. Screw a self-tapping screw into each, and pull on the screws with pliers to extract the seal. Alternatively carefully lever the oil seal out of position. 3 Clean the seal housing, and polish off any burrs or raised edges which may have caused the seal to fail in the first place. 4 Lubricate the lips of the new seal with clean engine oil, and press it into position using a suitable tubular drift (such as a socket) which bears only on the hard outer edge of the seal. Take care not to damage the seal lips during fitting; note that the seal lips should face inwards. 5 Refit the camshaft sprocket as described in Section 8. 10 Camshafts and followers removal, inspection and refitting 4 Removal 1 Remove the timing belt as described in Section 7. Prior to releasing the timing belt tension and removing the belt, rotate the crankshaft backwards by approximately 60° (4 teeth of movement); this will position the camshafts so that the valve spring pressure is evenly exerted along the complete length of the shaft, reducing the risk of the bearing caps being damaged on removal/refitting (see illustration). 2 Remove the camshaft sprockets as described in Section 8. 3 Starting on the inlet camshaft, working in a spiral pattern from the outside inwards, slacken the camshaft bearing cap retaining bolts by half-a-turn at a time, to relieve the pressure of the valve springs on the bearing caps gradually and evenly. Once the valve spring pressure has been relieved, the bolts can be fully unscrewed and removed along with the caps; the bearing caps and the cylinder head locations are numbered to ensure the caps are correctly positioned on refitting (see illustration). Take care not to loose the locating dowels (where fitted). 2.0 litre DOHC engine in-car repair procedures 2B•9 8 Examine the follower bearing surfaces which contact the camshaft lobes for wear ridges and scoring. Check the followers and their bores in the cylinder head for signs of wear or damage. If any follower is thought to be faulty or is visibly worn it should be renewed. Refitting 10.6 Using a rubber sucker to remove a camshaft follower Caution: If the bearing cap bolts are carelessly slackened, the bearing caps might break. If any bearing cap breaks then the complete cylinder head assembly must be renewed; the bearing caps are matched to the head and are not available separately. 4 Lift the camshaft out of the cylinder head and slide off the oil seal. 5 Repeat the operations described in paragraphs 3 and 4 and remove the exhaust camshaft. 6 Obtain sixteen small, clean plastic containers, and label them for identification. Alternatively, divide a larger container into compartments. Lift the followers out from the top of the cylinder head and store each one in its respective fitted position (see illustration). Note: Store all the followers the correct way up to prevent the oil draining from the hydraulic valve adjustment mechanisms. Inspection 7 Examine the camshaft bearing surfaces and cam lobes for signs of wear ridges and scoring. Renew the camshaft if any of these conditions are apparent. Examine the condition of the bearing surfaces both on the camshaft journals and in the cylinder head. If the head bearing surfaces are worn excessively, the cylinder head will need to be renewed. 9 Where removed, lubricate the followers with clean engine oil and carefully insert each one into its original location in the cylinder head. 10 Lubricate the camshaft followers with clean engine oil then lay the camshafts in position. Ensure the crankshaft is still positioned approximately 60° BTDC and position each camshaft so that the lobes of No1 cylinder are pointing upwards. Temporarily refit the sprockets to the camshafts and position each one so that its sprocket timing mark is approximately 4 teeth before its TDC alignment position. 11 Ensure the mating surfaces of the bearing caps and cylinder head are clean and dry and lubricate the camshaft journals and lobes with clean engine oil. 12 Apply a smear of sealant (Vauxhall recommend the use of sealant 15 03 170 available from your Vauxhall dealer) to the areas of the cylinder head mating surface around the sides of the inlet and exhaust camshaft front bearing cap oil seal apertures (see illustration). 13 Ensure the locating dowels (where fitted) are in position then refit the camshaft bearing caps and the retaining bolts in their original locations on the cylinder head. The caps are numbered from front to rear and the corresponding numbers are marked on the cylinder head upper surface. 14 Working on the inlet camshaft, tighten the bearing cap bolts by hand only then, working in a spiral pattern from the centre outwards, tighten the bolts by half-a-turn at a time to gradually impose the pressure of the valve springs on the bearing caps (see illustration). 10.12 Apply sealant to the shaded areas (arrowed) on each side of the inlet and exhaust camshaft oil seal apertures Repeat this sequence until all bearing caps are in contact with the cylinder head then go around and tighten the camshaft retaining bolts to the specified torque. Caution: If the bearing cap bolts are carelessly tightened, the bearing caps might break. If any bearing cap breaks then the complete cylinder head assembly must be renewed; the bearing caps are matched to the head and are not available separately. 15 Tighten the exhaust camshaft bearing cap bolts as described in paragraph 14. 16 Fit new camshaft oil seals as described in Section 9. 17 Refit the camshaft sprockets as described in Section 8. 18 Align all the sprocket timing marks to bring the camshafts and crankshaft back to TDC then refit the timing belt as described in Section 7. 19 Refit the camshaft cover and timing belt cover as described in Sections 4 and 6. 11 Cylinder head removal and refitting Removal Note: The engine must be cold when removing the cylinder head. New cylinder head bolts must be used on refitting. 1 Disconnect the battery negative lead. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Drain the cooling system and remove the spark plugs as described in Chapter 1. 3 Remove the inlet and exhaust manifolds as described in Chapter 4A. If no work is to be carried out on the cylinder head, the head can be removed complete with manifolds once the following operations have been carried out (see Chapter 4A). 10.14 Camshaft bearing cap tightening sequence (exhaust camshaft shown - inlet the same) 3510 Vauxhall/Opel Omega 4 2B 2B•10 2.0 litre DOHC engine in-car repair procedures the block, but do not lever at the mating faces. Note the fitted positions of the two locating dowels, and remove them for safe keeping if they are loose. 12 Recover the cylinder head gasket, and discard it. Preparation for refitting 11.19 Fit the new gasket to the cylinder block, engaging it with the locating dowels (arrowed) . . . 11.20 . . . making sure its OBEN/TOP marking is uppermost a) Remove the intake duct connecting the air cleaner to the throttle housing. b) Disconnect the wiring connectors from the throttle potentiometer, idle speed adjuster, EGR valve, purge valve, coolant temperature sensor, oxygen sensor and DIS module. Unbolt the earth connection from the fuel rail and release the wiring harness from its retaining clips. Lift the wiring cover squarely off of the injectors then disconnect the knock sensor and crankshaft sensor wiring connectors before positioning the wiring cover/harness clear of the cylinder head. c) Depressurise the fuel system then disconnect the fuel hoses from the fuel rail. d) Disconnect the various vacuum and coolant hoses from the inlet manifold/throttle housing. e) Unbolt the inlet manifold support bracket and the alternator upper brackets. f) Disconnect the accelerator cable. g) Remove the exhaust system front pipe. h) Disconnect the air hose from the secondary air injection system non-return valve on the exhaust manifold. 4 Remove the timing belt as described in Section 7. Prior to releasing the timing belt tension and removing the belt, rotate the crankshaft backwards by approximately 60° (4 teeth of movement); this will position the camshafts so that the valve spring pressure is evenly exerted along the complete length of the shafts, preventing the shafts turning and reducing the risk of the valves contacting the pistons (see illustration 10.1). 5 Remove the camshafts as described in Section 10. 6 Undo the retaining bolts securing the timing belt rear cover to the cylinder head. 7 Release the retaining clips and disconnect the various coolant hoses from the cylinder head/thermostat housing, noting each ones correct fitted location. 8 Unbolt the crankcase breather tube and remove it from the left-hand side of the cylinder block. Discard the gasket, a new one should be used on refitting. 9 Make a final check to ensure that all relevant hoses, pipes and wires, etc, have been disconnected. 10 Working in the reverse of the tightening sequence (see illustration 11.23), progressively slacken the cylinder head bolts by a quarter of a turn at a time until all bolts can be unscrewed by hand. Remove each bolt in turn, along with its washer. 11 Lift the cylinder head from the cylinder block. If necessary, tap the cylinder head gently with a soft-faced mallet to free it from 13 The mating faces of the cylinder head and block must be perfectly clean before refitting the head. Use a scraper to remove all traces of gasket and carbon, and also clean the tops of the pistons. Take particular care with the aluminium surfaces, as the soft metal is damaged easily. Also, make sure that debris is not allowed to enter the oil and water channels - this is particularly important for the oil circuit, as carbon could block the oil supply to the camshaft or crankshaft bearings. Using adhesive tape and paper, seal the water, oil and bolt holes in the cylinder block. To prevent carbon entering the gap between the pistons and bores, smear a little grease in the gap. After cleaning the piston, rotate the crankshaft so that the piston moves down the bore, then wipe out the grease and carbon with a cloth rag. Clean the piston crowns in the same way. 14 Check the block and head for nicks, deep scratches and other damage. If slight, they may be removed carefully with a file. More serious damage may be repaired by machining, but this is a specialist job. 15 If warpage of the cylinder head is suspected, use a straight-edge to check it for distortion. Refer to Chapter 2D if necessary. 16 Ensure that the cylinder head bolt holes in the crankcase are clean and free of oil. Syringe or soak up any oil left in the bolt holes. This is most important in order that the correct bolt tightening torque can be applied and to prevent the possibility of the block being cracked by hydraulic pressure when the bolts are tightened. 17 Renew the cylinder head bolts regardless of their apparent condition. Refitting 11.23 Cylinder head bolt tightening sequence 3510 Vauxhall/Opel Omega 18 Ensure the crankshaft is till positioned approximately 60° BTDC and wipe clean the mating faces of the head and block. 19 Ensure that the two locating dowels are in position at each end of the cylinder block/crankcase surface (see illustration). 20 Fit the new cylinder head gasket to the block, making sure it is fitted with the correct way up with its OBEN or TOP mark uppermost and at the front end of the engine (see illustration). 21 Carefully refit the cylinder head, locating it on the dowels. 22 Fit the washers to the new cylinder head bolts then carefully insert them into position (do not drop), tightening them finger-tight only at this stage. 23 Working progressively and in the sequence shown, first tighten all the cylinder head bolts to the stage 1 torque setting (see illustration). 2.0 litre DOHC engine in-car repair procedures 2B•11 24 Once all bolts have been tightened to the stage 1 torque, again working in the sequence shown, tighten each bolt through its specified stage 2 angle, using a socket and extension bar. It is recommended that an anglemeasuring gauge is used during this stage of the tightening, to ensure accuracy. 25 Working in the specified sequence, go around again and tighten all bolts through the specified stage 3 angle. 26 Working again in the specified sequence, go around and tighten all bolts through the specified stage 4 angle. 27 Finally go around in the specified sequence again and tighten all bolts through the specified stage 5 angle. 28 Ensure the mating surfaces are clean and dry then refit the breather tube to the cylinder block and tighten its retaining bolts to the specified torque. 29 Reconnect the coolant hoses, securing them in position with the retaining clips. 30 Refit the timing belt rear cover retaining bolts and tighten them to the specified torque. 31 Refit the camshafts as described in Section 10. 32 Align all the sprocket timing marks to bring the camshafts and crankshaft back to TDC then refit the timing belt as described in Section 7. 33 Refit the camshaft cover and timing belt cover(s) as described in Sections 4 and 5. 34 Refit/reconnect the inlet and exhaust manifolds (see Chapter 4A). 35 Ensure all pipes and hoses are securely reconnected then refill the cooling system and refit the spark plugs as described in Chapter 1. 36 Reconnect the battery then start the engine and check for signs of leaks. 12 Sump removal and refitting 4 Note: There are two possible types of sump fitted to these engines; early models had a onepiece sump made of pressed steel and later models had a two-piece sump arrangement with a small pressed steel sump pan being fitted to the base of the main sump casting which is made of aluminium alloy. Proceed as described under the relevant heading One-piece sump Note: A new baffle plate will be required on refitting (the sump gasket is an integral part of the plate). Removal 1 Disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Firmly apply the handbrake then jack up the front of the car and support it on axle stands. Undo the retaining screws and remove the undercover from beneath the engine. 3 Drain the engine oil as described in Chapter 1, then fit a new sealing washer and refit the drain plug, tightening it to the specified torque. 4 Where necessary, disconnect the wiring connector from the oil level sender unit on the sump. 5 Slacken and remove the bolts securing the support brackets to the transmission housing and sides of the cylinder block. Remove both brackets from the engine then remove the flywheel lower cover plate from the base of the transmission housing. 6 Slacken and remove the nuts securing the left- and right-hand engine mounting brackets to the top of the rubber mountings. Unbolt the right-hand mounting bracket and remove it from the cylinder block. 7 Attach an engine hoist to the cylinder head lifting brackets then raise the hoist until it is supporting the weight of the engine. 8 Progressively slacken and remove the bolts securing the sump to the base of the cylinder block/oil pump. Break the sump joint by striking the sump with the palm of the hand, then lower the sump away from the engine and withdraw it. Raise the engine unit slightly to gain the necessary clearance required for sump removal, taking care not to place any excess strain on the engine wiring/hoses or exhaust system. 9 Undo the retaining bolts and remove the oil pump pick-up/strainer from the base of the oil pump housing, noting the sealing ring, then remove the baffle plate assembly. 10 Check the oil pump pick-up/strainer for signs of clogging or splitting and renew/clean as necessary. Note: If the sump is to be removed for any length of time, refit the mounting bracket to the cylinder block and lower the engine back down onto its mounting rubbers. Refitting 11 Remove all traces of dirt and oil from the mating surfaces of the sump, cylinder block and oil pump housing. Also remove all traces of locking compound from the threads of the oil pump pick-up/strainer bolts and the sump retaining bolts. 12 Apply a smear of suitable sealant (Vauxhall recommend the use of sealant 15 03 295 - available from your Vauxhall dealer) to the areas of the cylinder block mating surface around the areas of the oil pump housing and rear main bearing cap joints. 13 Fit a new sealing ring to the oil pump pickup/strainer and apply a few drops of locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of the strainer retaining bolts. 14 Offer up the new baffle plate, making sure it is correctly located, then refit the oil pump strainer tightening its retaining bolts to the specified torque. 3510 Vauxhall/Opel Omega 15 Apply a drop of the locking compound to each of the sump retaining bolts then offer up the sump to the cylinder block. Refit the retaining bolts and progressively tighten them to the specified torque, working out from the centre in a diagonal sequence. 16 Refit the mounting bracket to the cylinder block and tighten its retaining bolts to the specified torque. Lower the engine back down onto its mountings making sure the brackets and mounting rubbers are correctly aligned. Remove the hoist from the engine then refit the mounting nuts, tightening them to the specified torque setting. 17 Refit the flywheel lower cover plate to the transmission housing then refit the support brackets. Screw in the bolts securing the brackets to the cylinder block and transmission housing and tighten them to their specified torque settings. 18 Reconnect the oil level sender wiring connector (where fitted). 19 Refit the undercover then lower the vehicle to the ground then fill the engine with fresh oil, with reference to Chapter 1. Two-piece sump Note: New sump pan retaining bolts and front suspension subframe mounting bolts will be required on refitting. New retaining nuts for the centre tie rod will also be required. Removal 20 Carry out the operations described in paragraphs 1 to 3. 21 Referring to Chapter 12, on models with Xenon headlights, disconnect the wiring connector from the headlight system front vehicle level control sensor then unclip the link rod from the sensor arm balljoint. 22 Remove the steering linkage centre tie rod as described in Chapter 10, Section 25. 23 Slacken and remove the nuts securing the engine left- and right-hand mountings to the subframe. 24 Attach an engine hoist to the cylinder head lifting brackets then raise the hoist until it is supporting the weight of the engine. Alternatively use an engine support bar to take the weight of the engine. 25 Referring to Chapter 10, unscrew the front suspension subframe front mounting bolts by approximately 4 turns. Support the rear of the subframe with a jack then slacken and remove the rear mounting bolts. Lower the rear of the subframe approximately 10 cm to gain access to the sump pan. 26 If an oil level sensor is fitted, disconnect the wiring connector from the sensor connector on the left-hand side of the main casting then slide off the retaining clip and push the connector into the sump. 27 Slacken and remove the bolts securing the sump pan to the main casting then free the pan and remove it along with its gasket. On models with an oil level sensor, take care not to damage the sensor wiring as the pan is removed. 2B 2B•12 2.0 litre DOHC engine in-car repair procedures 13.7 Undo the retaining screws and remove the oil pump cover 13.9 Lift the inner and outer gears (arrowed) out from the pump housing 28 To remove the main casting from the engine, disconnect the wiring connector from the oil temperature sensor (where fitted) then slacken and remove the bolts securing the exhaust front pipe mounting bracket in position. 29 Unscrew the bolts securing the main casting flange to the transmission housing then progressively slacken and remove the bolts securing the casting to the base of the cylinder block/oil pump. Break the joint by striking the casting with the palm of the hand, then lower it away from the engine and withdraw it. Remove the gasket and discard it. Note: If the sump pan/main casting are to be removed for any length of time, raise the subframe back up into position and refit its mounting bolts then lower the engine back down onto the subframe. 30 While the sump is removed, take the opportunity to check the oil pump pickup/strainer for signs of clogging or splitting. If necessary, unbolt the pick-up/strainer and remove it from the base of the oil pump housing along with its sealing ring. The strainer can then be cleaned easily in solvent or renewed. 32 Where necessary, position a new sealing ring on top of the oil pump pick-up/strainer and fit the strainer. Apply locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of the retaining bolts then fit the bolts and tighten to the specified torque. 33 Apply a smear of suitable sealant (Vauxhall recommend the use of sealant 15 03 295 - available from your Vauxhall dealer) to the areas of the cylinder block mating surface around the areas of the oil pump housing and rear main bearing cap joints. 34 Fit a new gasket to the main casting then apply a drop of locking compound to the threads of the casting to cylinder block/oil pump bolts. Manoeuvre the casting into position, ensuring the gasket is correctly positioned, then loosely refit all the retaining bolts and the exhaust front pipe mounting bracket. 35 Working out from the centre in a diagonal sequence, progressively tighten the bolts securing the main casting to the cylinder block/oil pump to their specified torque setting. 36 Tighten the bolts securing the main casting flange to the transmission housing to their specified torque settings then securely tighten the exhaust bracket bolts. Where necessary, reconnect the oil temperature sensor. 37 Ensure the sump pan and main casting surfaces are clean and dry, place a new gasket on the top of the pan and offer it up to the main casting. On models with an oil level sensor, fit a new sealing ring to the wiring connector and seat the wiring connector in the main casting, securing it in position with the retaining clip, prior to seating the sump pan on the main casting. 38 Fit the new sump pan retaining bolts then go around in a diagonal sequence and tighten them to the specified stage 1 torque setting. Once all bolts have been tightened go around again and angle-tighten them through the specified stage 2 angle. It is recommended that an angle-measuring gauge is used during this stage of the tightening, to ensure accuracy. 39 Reconnect the oil level sender wiring connector (where necessary). Refitting 31 Remove all traces of dirt and oil from the mating surfaces of the sump pan, main casting and cylinder block and (if necessary) the pick-up/strainer and oil pump housing. Also remove all traces of locking compound from the main casting bolts and (where removed) the pick-up/strainer bolts. 13.10 Oil pressure relief valve components 1 Plunger 2 Spring 3 Sealing washer 4 Valve bolt 3510 Vauxhall/Opel Omega 40 Raise the subframe back up into position making sure the engine mounting lugs engage correctly with the subframe cutouts. Fit the four new rear retaining bolts then remove the subframe front retaining bolts and fit the new ones. Tighten the subframe mounting bolts to their specified torque setting and then through the specified angles as described in Chapter 10. 41 Remove the hoist from the engine then refit the nuts securing the engine mountings to the subframe, tightening them to the specified torque. 42 Refit the steering linkage centre tie rod as described in Chapter 10 43 On models with Xenon headlights clip the link rod balljoint back onto the vehicle level control sensor and reconnect the wiring connector (see Chapter 12). 44 Refit the undercover then lower the vehicle to the ground then fill the engine with fresh oil, with reference to Chapter 1. 13 Oil pump removal, overhaul and refitting 4 Removal 1 Drain the engine oil as described in Chapter 1, then fit a new sealing washer and refit the drain plug, tightening it to the specified torque. Remove the oil filter and discard it. 2 Remove the timing belt as described in Section 7. 3 Remove the rear timing belt cover as described in Section 6. 4 Remove the sump and oil pump pickup/strainer as described in Section 12. 5 Disconnect the wiring connector from the oil pressure switch. 6 Slacken and remove the retaining bolts then slide the oil pump housing assembly off of the end of the crankshaft, taking great care not to lose the locating dowels. Remove the housing gasket and discard it. Overhaul 7 Undo the retaining screws and lift off the pump cover from the rear of the housing (see illustration). 8 Using a suitable marker pen, mark the surface of both the pump inner and outer gears; the marks can then be used to ensure the gears are refitted the correct way around. 9 Lift out the inner and outer gears from the pump housing (see illustration). 10 Unscrew the oil pressure relief valve bolt from the front of the housing and withdraw the spring and plunger from the housing, noting which way around the plunger is fitted (see illustration). Remove the sealing washer from the valve bolt. Note: The pressure relief valve can be removed with pump in position on the engine unit. On models with air conditioning it will be necessary to unbolt the compressor mounting bracket assembly from the block to allow the valve to be removed. 2.0 litre DOHC engine in-car repair procedures 2B•13 13.12a Using a feeler blade to check gear clearance 13.12b Using a straight edge and feeler blade to measure gear endfloat 13.14 Fitting a new crankshaft oil seal to the oil pump housing 11 Clean the components, and carefully examine the gears, pump body and relief valve plunger for any signs of scoring or wear. Renew any component which shows signs of wear or damage; if the gears or pump housing are marked then the complete pump assembly should be renewed. 12 If the components appear serviceable, measure the clearance between the inner and outer gears using feeler blades. Also measure the gear endfloat, and check the flatness of the end cover (see illustrations). If the clearances exceed the specified tolerances, the pump must be renewed. 13 If the pump is satisfactory, reassemble the components in the reverse order of removal, noting the following. a) Ensure both gears are fitted the correct way around. b) Fit a new sealing ring to the pressure relief valve bolt and tighten the bolt to the specified torque. c) Tighten the pump cover screws to the specified torque. d) On completion prime the oil pump by filling it with clean engine oil whilst rotating the inner gear. 20 Refit the oil pump pick-up/strainer and sump as described in Section 12. 21 Refit the rear timing belt cover to the engine, tightening its retaining bolts to the specified torque. 22 Refit the timing belt sprockets, idler pulleys and tensioner then refit the belt as described in Sections 7 and 8. 23 On completion, fit a new oil filter and fill the engine with clean oil as described in Chapter 1. number 1 cylinder at TDC. With number 1 piston at TDC the flats on the end of each balancer shaft should be correctly aligned (see paragraph 5). 3 Evenly and progressively slacken and remove the retaining bolts then remove the balancer unit from the base of the cylinder block along with the spacer plate which is fitted between the unit and block. The spacer plate is used to adjust the balancer unit gear teeth backlash (see paragraph 10). Refitting 14 Crankshaft balancer unit (1998 model year onwards) removal, refitting and adjustment 4 Note: New balancer unit retaining bolts will be required on refitting. Removal 1 Remove the sump and oil pump pickup/strainer pipe as described in Section 12. 2 Using a socket on the crankshaft sprocket bolt, rotate the crankshaft in the normal direction of rotation until the notch on the pulley rim is correctly aligned with the pointer on the timing belt cover. This positions 4 If any work has been carried out on the crankshaft or a new balancer is being installed, it will be necessary to adjust the gear teeth backlash prior to refitting. If the original balancer unit is to be refitted and no work has being carried out on the crankshaft it is permissible to refit the unit with the original spacer plate without checking the gear backlash. 5 Ensure the crankshaft pulley notch is still correctly aligned with the pointer on the rear cover then rotate the balancer unit gears until the flats on the gear shaft ends are facing downwards and are in line with each other (see illustration). Refitting 14 Prior to refitting, carefully lever out the crankshaft oil seal using a flat-bladed screwdriver. Fit the new oil seal, ensuring its sealing lip is facing inwards, and press it squarely into the housing using a tubular drift which bears only on the hard outer edge of the seal (see illustration). Press the seal into position so that it is flush with the housing and lubricate the oil seal lip with clean engine oil. 15 Ensure the mating surfaces of the oil pump and cylinder block are clean and dry and the locating dowels are in position. 16 Fit a new gasket to the cylinder block. 17 Carefully manoeuvre the oil pump into position and engage the inner gear with the crankshaft end. Locate the pump on the dowels, taking great care not damage the oil seal lip. 18 Refit the pump housing retaining bolts in their original locations and tighten them to the specified torque. 19 Reconnect the oil pressure sensor wiring connector. 14.5 With number 1 cylinder at TDC the balancer unit gear shaft flats should be correctly aligned as shown 3510 Vauxhall/Opel Omega 2B 2B•14 2.0 litre DOHC engine in-car repair procedures 14.12 Using service tool KM-949 to check the balancer unit gear teeth backlash. Ensure the dial gauge is positioned at a right-angle to the arm and is correctly seated in the arm groove 1 Right-hand thumbwheel 2 Left-hand thumbwheel 3 Measuring arm base 4 Dial gauge 5 Measuring arm 6 Fit the spacer plate to the top of the balancer unit then refit the balancer unit to the cylinder block. Ensure the shaft gear is correctly engaged with the crankshaft gear, and screw in the new retaining bolts. 7 Tighten all the bolts by hand then check that the crankshaft pulley mark and balance shaft flats are still correctly aligned. If not, remove the balancer unit and make any necessary adjustments before refitting it to the cylinder block. 8 Once the balancer unit is correctly timed with the crankshaft, go around in a diagonal sequence and tighten the retaining bolts to the specified stage 1 torque setting. Once all bolts have been tightened go around again and angle-tighten them through the specified stage 2 angle. It is recommended that an angle-measuring gauge is used during this stage of the tightening, to ensure accuracy. 9 Refit the oil pump pick-up/strainer and sump as described in Section 12. Adjustment Note: The following procedure can only be accurately carried out using Vauxhall service tool KM-949 and a dial gauge. 10 If work has been carried out on the crankshaft or a new balancer unit is being fitted, it is necessary to check the balancer unit gear teeth backlash. The backlash is controlled by the thickness of the spacer plate which is fitted in between the balancer unit and the cylinder block. The spacer is available in the following thicknesses; the thickness can be determined by direct measurement or by the identification marking on the stamped on it. Plate thickness Identification marking 0.535 to 0.565 mm 55 0.565 to 0.595 mm 58 0.595 to 0.625 mm 61 0.625 to 0.655 mm 64 0.655 to 0.685 mm 67 0.685 to 0.715 mm 70 0.715 to 0.745 mm 73 0.745 to 0.775 mm 76 0.775 to 0.805 mm 79 0.805 to 0.835 mm 82 0.835 to 0.865 mm 85 11 The backlash is measured with the balancer unit correctly installed on the cylinder block. If a new balancer unit is being fitted, obtain the thickest spacer plate available (identification marking 85) and fit the balancer unit to the cylinder block using the original retaining bolts (see paragraphs 5 to 8). 12 Position number 1 cylinder at TDC (see paragraph 2) and fit the service tool KM-949. Fit the measuring arm to the right-hand (inlet manifold side) shaft, ensuring the arm is horizontal, then screw both knurled thumbwheels into the balancer shafts and tighten securely. Position the dial gauge so that it is at a right-angle to the measuring arm and its pointer is seated correctly in the arm groove (see illustration). 13 Using the knurled thumbwheel, rotate the left-hand (exhaust manifold side) balancer shaft fully clockwise then zero the dial gauge. Rotate the shaft fully anti-clockwise and measure the movement of the arm on the gauge, noting this figure down on paper. 14 Position the dial gauge clear of the measuring arm then rotate the crankshaft through 45° (the balance shafts will rotate 90°). Slacken the right-hand thumbwheel and return the measurement arm to the horizontal position before tightening it securely then take the backlash measurement again. 15 Repeat this procedure twice more until a total of four backlash measurements have been obtained. 16 All four backlash measurements should be within the range of 0.02 to 0.06 mm. If any one of the four measurements is outside this range then adjustment is necessary. 17 If adjustment is necessary, remove the balancer unit from the cylinder block and recover the spacer plate. Identify the thickness of the spacer plate (see paragraph 10). The backlash measurements are decreased by fitting a thinner spacer plate and increased by fitting a thicker plate. Calculate the correct thickness of spacer plate required noting that each plate thickness 3510 Vauxhall/Opel Omega increases/decreases (as applicable) the backlash measurement by approximately 0.02 mm. For example, if a backlash measurement of 0.07 mm was obtained and a spacer plate with the identification marking 67 was installed, fitting a spacer plate with the identification marking 64 will decrease the measurement by approximately 0.02 mm and bring the backlash to within the specified limit. 18 Select the correct thickness of spacer plate required then refit the balancer unit as described in paragraphs 5 to 9. 15 Flywheel/driveplate removal, inspection and refitting Refer to Chapter 2A, Section 15. 16 Crankshaft oil seals renewal 4 Front (timing belt end) oil seal 1 Remove the crankshaft sprocket as described in Section 8. 2 Carefully punch or drill two small holes opposite each other in the oil seal. Screw a self-tapping screw into each and pull on the screws with pliers to extract the seal. Alternatively carefully lever the seal out of position. Caution: Great care must be taken to avoid damage to the oil pump 3 Clean the seal housing and polish off any burrs or raised edges which may have caused the seal to fail in the first place. 4 Lubricate the lips of the new seal with clean engine oil and ease it into position on the end of the shaft. Press the seal squarely into position until it is flush with the housing. If necessary, a suitable tubular drift, such as a socket, which bears only on the hard outer edge of the seal can be used to tap the seal into position. Take great care not to damage the seal lips during fitting and ensure that the seal lips face inwards. 5 Wash off any traces of oil, then refit the crankshaft sprocket as described in Section 8. Rear (flywheel/driveplate end) oil seal 6 Remove the flywheel/driveplate as described in Chapter 2A, Section 15. 7 Renew the seal as described in paragraphs 2 to 4. 8 Refit the flywheel/driveplate as described in Chapter 2A, Section 15. 17 Engine/transmission mountings inspection and renewal Refer to Chapter 2A, Section 17. 2C•1 Chapter 2 Part C: 2.5 and 3.0 litre engine in-car repair procedures Contents Camshaft covers - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 4 Camshaft oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Camshafts and followers - removal, inspection and refitting . . . . . . 10 Compression test - description and interpretation . . . . . . . . . . . . . . 2 Crankshaft oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Crankshaft pulley - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 5 Cylinder heads - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 11 Engine oil and filter - renewal . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Engine oil level check . . . . . . . . . . . . . . . . . . . . . . .See Weekly checks Engine/transmission mountings - inspection and renewal . . . . . . . . 17 Flywheel/driveplate - removal, inspection and refitting . . . . . . . . . . . 15 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Oil cooler - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Oil pump - removal, overhaul and refitting . . . . . . . . . . . . . . . . . . . . 13 Sump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Timing belt - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Timing belt covers - removal and refitting . . . . . . . . . . . . . . . . . . . . . 6 Timing belt sprockets, tensioner and guide pulleys - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Top dead centre (TDC) for No 1 piston - locating . . . . . . . . . . . . . . . 3 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 2C Specifications General Engine type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manufacturer’s engine code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direction of crankshaft rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compression ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V6 water-cooled. Double overhead camshaft, belt-driven 2.5 litre engine 3.0 litre engine X25XE X30XE 81.6 mm 86.0 mm 79.6 mm 85.0 mm 2498 cc 2969 cc 125 kW at 6000 rpm 155 kW at 6200 rpm 227 Nm at 3200 rpm 270 Nm at 3600 rpm 1-2-3-4-5-6 (No 1 cylinder at timing belt end of right-hand cylinder bank) Clockwise (viewed from timing belt end of engine) 10.8:1 Compression pressures Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum difference between any two cylinders . . . . . . . . . . . . . . . . . . 12 to 15 bar (174 to 218 psi) 1 bar (15 psi) Camshaft Cam lift: 2.5 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 mm 10.0 mm Lubrication system Oil pump type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Minimum permissible oil pressure at idle speed, with engine at operating temperature (oil temperature of at least 80°C) . . . . . . . . Oil pump rotor endfloat: Inner rotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Outer rotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rotor-type, driven directly from crankshaft 1.5 bar (22 psi) Less than 0.08 mm Less than 0.10 mm 3510 Vauxhall/Opel Omega 2C•2 2.5 and 3.0 litre engine in-car repair procedures Torque wrench settings Auxiliary drivebelt tensioner bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Baffle plate bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Camshaft bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Camshaft cover bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Camshaft sensor bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Camshaft sprocket bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Connecting rod big-end bearing cap bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coolant pipe (right-hand)-to-cylinder block bolts . . . . . . . . . . . . . . . . . Coolant pipe/dipstick tube/engine lifting bracket bolt . . . . . . . . . . . . . . Coolant pump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coolant pump pulley bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankcase breather housing bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft pulley bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft sensor rotor bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft sprocket bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder head bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder head coolant outlet bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Driveplate bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine/transmission mounting bolts: Left- and right-hand mountings: Mounting-to-subframe nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mounting-to-mounting bracket nut . . . . . . . . . . . . . . . . . . . . . . . . . Mounting bracket-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . Vibration damper bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear mounting: Mounting-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . Mounting-to-crossmember nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . Crossmember-to-body bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine-to-transmission unit bolts: Transmission-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . . . . . . Transmission-to-sump flange bolts . . . . . . . . . . . . . . . . . . . . . . . . . . Flywheel bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main bearing cap/bridge casting: Main bearing cap bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Casting threaded sleeves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Casting-to-cylinder block (M8) bolts . . . . . . . . . . . . . . . . . . . . . . . . . Oil cooler: Cover bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cover nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil cooler pipe union nuts and bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nm 35 8 8 8 8 lbf ft 26 6 6 6 6 50 Angle-tighten a further 60° Angle-tighten a further 15° 37 35 Angle-tighten a further 45° Angle-tighten a further 15° 20 25 25 26 8 Angle-tighten a further 30° Angle-tighten a further 30° 8 20 15 15 18 18 6 6 15 11 250 Angle-tighten a further 45° Angle-tighten a further 15° 185 25 Angle-tighten a further 90° Angle-tighten a further 90° Angle-tighten a further 90° Angle-tighten a further 15° 30 18 22 65 Angle-tighten a further 30° Angle-tighten a further 15° 48 55 40 60 40 41 30 44 30 40 20 45 30 15 33 60 40 44 30 65 Angle-tighten a further 30° Angle-tighten a further 15° 48 50 Angle-tighten a further 60° Angle-tighten a further 15° 8 20 37 6 15 20 30 30 15 22 22 3510 Vauxhall/Opel Omega 2.5 and 3.0 litre engine in-car repair procedures 2C•3 Torque wrench settings (continued) Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil pump cover screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil pump retaining bolts - see text for details: M6 bolts with original timing belt rear cover: Initial torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M6 bolts with modified timing belt rear cover . . . . . . . . . . . . . . . . . . M8 bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil pump pick-up/strainer bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power steering pump pulley bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sump bolts: Sump pan bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main casting bolts: Casting-to-cylinder block/oil pump bolts . . . . . . . . . . . . . . . . . . . . Casting flange-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . Sump drain plug: Hex-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torx-head bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt cover bolts: Outer cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear cover: M6 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M8 threaded stud . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt lower guide pulley bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing belt tensioner pulley/upper guide pulley assembly: Backplate-to-cylinder head bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tensioner pulley nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Guide pulley bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nm 15 8 lbf ft 11 6 8 10 10 6 7 7 12 20 8 9 15 6 20 Angle-tighten a further 30° Angle-tighten a further 15° 15 8 Angle-tighten a further 30° 6 15 40 11 30 55 10 41 7 8 6 8 10 40 6 7 30 40 20 40 30 15 30 2C 1 General information How to use this Chapter 1 This Part of Chapter 2 is devoted to in-car repair procedures for the engine. All procedures concerning engine removal and refitting, and engine block/cylinder head overhaul can be found in Chapter 2D. 2 Most of the operations included in this Part are based on the assumption that the engine is still installed in the car. Therefore, if this information is being used during a complete engine overhaul, with the engine already removed, many of the steps included here will not apply. Engine description 3 The engine is a double overhead camshaft, V6 unit, mounted at the front of the car with the transmission on its rear. The cylinder banks are arranged at a 54° angle to keep the engine as compact as possible. This engine is often referred to as the V6 ECOTEC engine (Emission Consumption Optimized TEChnology). 4 The cylinder block is of the dry-liner type. The crankshaft is supported within the cylinder block on four shell-type main bearings. Thrustwashers are fitted to number 4 (flywheel/ driveplate end) main bearing, to control crankshaft endfloat. 5 The aluminium alloy pistons are of the slipper type, and are fitted with three piston rings, comprising two compression rings and a scraper-type oil control ring. The pistons are joined to the connecting rods by gudgeon pins; on 2.5 litre engines the pins are an interference-fit and on 3.0 litre engines the pins are secured in position with circlips. On all engines, the connecting rods are attached to the crankshaft by horizontally split shelltype big-end bearings. 6 The camshafts run directly in the cylinder heads, and are driven by the crankshaft via a toothed rubber timing belt. The camshafts operate each valve via a follower. Each follower incorporates a hydraulic selfadjusting valve which automatically adjust the valve clearances. 7 Lubrication is by pressure-feed from a rotor-type oil pump, which is mounted on the front end of the crankshaft. It draws oil through a strainer located in the sump, and then forces it through an externally mounted 3510 Vauxhall/Opel Omega full-flow cartridge-type filter. The oil flows into galleries in the main bearing cap bridge arrangement and cylinder block/crankcase, from where it is distributed to the crankshaft (main bearings) and camshafts. The big-end bearings are supplied with oil via internal drillings in the crankshaft, while the camshaft bearings also receive a pressurised supply. The camshaft lobes and valves are lubricated by splash, as are all other engine components. An oil cooler is fitted to help keep the oil temperature stable under arduous operating temperatures; the cooler is fitted to the top of the cylinder block where it is located in between the cylinder banks. 8 A semi-closed crankcase ventilation system is employed; crankcase fumes are drawn from cylinder head cover, and passed via a hose to the inlet manifold. Repair operations possible with the engine in the car 9 The following operations can be carried out without having to remove the engine from the vehicle. a) Removal and refitting of the cylinder heads. b) Removal and refitting of the timing belt and sprockets. 2C•4 2.5 and 3.0 litre engine in-car repair procedures 3.5a Align the relevant camshaft sprockets timing marks with the cutouts on the timing belt rear cover (arrowed) on both the righthand . . . c) Renewal of the camshaft oil seals. d) Removal and refitting of the camshafts and followers. e) Removal and refitting of the sump. f) Removal and refitting of the connecting rods and pistons*. g) Removal and refitting of the oil pump. h) Renewal of the crankshaft oil seals. i) Renewal of the engine mountings. j) Removal and refitting of the flywheel/driveplate. * Although the operation marked with an asterisk can be carried out with the engine in the car after removal of the sump, it is better for the engine to be removed, in the interests of cleanliness and improved access. For this reason, the procedure is described in Chapter 2D. 2 Compression test description and interpretation Refer to Chapter 2A, Section 2. 3 Top dead centre (TDC) for No 1 piston locating 3 1 In its travel up and down its cylinder bore, Top Dead Centre (TDC) is the highest point that each piston reaches as the crankshaft rotates. While each piston reaches TDC both at the top of the compression stroke and again at the top of the exhaust stroke, for the purpose of timing the engine, TDC refers to the piston position (usually number 1) at the top of its compression stroke. 2 Number 1 piston (and cylinder) is at the front (timing belt) end of the right-hand cylinder bank, and its TDC position is located as follows. Note that the crankshaft rotates clockwise when viewed from the front of the vehicle. 3.5b . . . and left-hand cylinder heads (arrowed) . . . 3 Disconnect the battery negative terminal. If necessary, remove all the spark plugs as described in Chapter 1 to enable the engine to be easily turned over. 4 Remove the timing belt outer cover to gain access to the camshaft sprocket timing marks (see Section 6). 5 Using a socket and extension bar on the crankshaft sprocket bolt, rotate the crankshaft until the relevant timing marks on the camshaft sprockets are all at the top and are correctly aligned with the marks on the timing belt rear cover. Each sprocket has two timing marks the correct mark to use is as follows (see illustrations). Camshaft Timing mark to be used Right-hand cylinder head exhaust 1 Right-hand cylinder head inlet 2 Left-hand cylinder head inlet 3 Left-hand cylinder head exhaust 4 6 With the camshaft sprocket marks correctly positioned, align the notch on the crankshaft pulley rim with the pointer on the oil pump housing (see illustration). The engine is now positioned with No1 piston at TDC on its compression stroke. Note: If the crankshaft pulley has been removed, use the mark on the crankshaft sprocket rim. The mark should be aligned with the cutout on the base of the oil pump housing (see Section 7). 4 Camshaft covers removal and refitting 3 Removal 1 Remove the inlet manifold as described in Chapter 4A. Right-hand cover 2 Disconnect the plug caps from the plugs then unclip the HT leads and position them clear of the cover. 3 Evenly and progressively slacken and remove the camshaft cover retaining bolts. 4 Lift the camshaft cover away from the cylinder head and recover the cover seals and the sealing rings which are fitted to each of the retaining bolt holes. Examine the seal and sealing rings for signs of wear or damage and renew if necessary. Left-hand cover 3.6 . . . and the crankshaft pulley notch with the pointer on the oil pump housing (arrowed) to position No1 piston at TDC on its compression stroke 3510 Vauxhall/Opel Omega 5 To improve access, remove the windscreen wiper arms and the water deflector panel (see Chapter 12, Sections 15 and 16). Access can be further improved by disconnecting the engine wiring harness as described in paragraphs 14 to 16 of Section 11 and positioning it clear of the cover. 6 On models with air conditioning, unbolt the air conditioning pipe/hose bracket from the front of the cylinder head and position the hose/pipe to one side. 7 Lift the oil filler neck retaining tab then twist the neck anti-clockwise and remove it from the top of the cover (see illustrations). Recover the neck sealing ring and discard it; a new one should be used on refitting. 2.5 and 3.0 litre engine in-car repair procedures 2C•5 4.7a Lift the retaining tab (arrowed) . . . 8 Remove the cover as described paragraphs 3 and 4 (see illustration). 4.7b . . . and rotate the oil filler neck anticlockwise to free it from the left-hand camshaft cover 4.8 Removing the left-hand camshaft cover 4.9a Fit the new seals securely to the cover grooves . . . 4.9b . . . and install the sealing rings in the bolt hole grooves in Refitting Right-hand cover 9 Ensure the cover and cylinder head surfaces are clean and dry then fit the seals securely to the cover grooves. Fit the sealing rings to the recesses around each retaining bolt hole, holding them in position with a smear of grease (see illustrations). 10 Apply a smear of suitable sealant (Vauxhall recommend the use of sealant 15 03 295 - available from your Vauxhall dealer) to the areas of the cylinder head surface around the front inlet and exhaust camshaft bearing caps and also to the semi-circular cutouts on the rear of the head (see illustrations). 11 Carefully manoeuvre the camshaft cover into position, taking great care to ensure all the sealing rings remain correctly seated. 12 Refit the cover retaining bolts and tighten the retaining bolts to the specified torque, working in a spiral pattern from the centre outwards. 13 Securely reconnect the plug caps to the spark plugs making sure the HT leads are clipped securely in position. 14 Refit the inlet manifold as described in Chapter 4A. Left-hand cover 15 Refit the cover as described in paragraphs 9 to 12. 16 Fit a new sealing ring to the filler neck then refit the neck to the cover making sure its retaining tab is correctly engaged with the cover retaining bolt. 17 Where necessary, refit the air conditioning pipe/hose retaining clip and securely tighten its retaining bolt. 18 Refit the windscreen wiper motor cover panel and wiper arms as described in Chapter 12. Where necessary, reconnect the engine wiring harness making sure the wiring 4.10a Apply sealant to the areas at the sides of the camshaft front bearing caps (arrowed) . . . is correctly routed and all connectors are securely connected. 5 Crankshaft pulley removal and refitting 2 Removal 1 Remove the auxiliary drivebelt as described in Chapter 1. Prior to removal, mark the direction of rotation on the belt to ensure the belt is refitted the same way around. 4.10b . . . and also to the semi-circular cut-outs (arrowed) on the rear of the cylinder head 3510 Vauxhall/Opel Omega 2C 2C•6 2.5 and 3.0 litre engine in-car repair procedures 6.4a Retain the coolant pump shaft with an open-ended spanner then undo the retaining bolts . . . 6.4b . . . and remove the pulley from the engine 2 Using a socket and extension bar on the crankshaft sprocket bolt, turn the crankshaft until the notch on the pulley rim is correctly aligned with the pointer on the cover. 3 Slacken and remove the small retaining bolts securing the pulley to the crankshaft sprocket and remove the pulley from the engine. If necessary, prevent crankshaft rotation by holding the sprocket retaining bolt with a suitable socket. 5 Refit the auxiliary drivebelt as described in Chapter 1 using the mark made prior to removal to ensure the belt is fitted the correct way around. Refitting Outer cover 4 Check that the crankshaft sprocket mark is still aligned with the mark on the oil pump housing then manoeuvre the crankshaft pulley into position. Align the notch on the pulley rim with the pointer then seat the pulley on the sprocket and tighten its retaining bolts to the specified torque. Note: New coolant pump and power steering pump pulley bolts will be required on refitting. 6.5a Insert a socket and extension bar through the power steering pump pulley then undo the retaining bolts . . . 6.7b . . . and right-hand covers and position the wiring harness clear of the tray 6 Timing belt covers removal and refitting 4 Removal 1 Remove the multi-ram air intake system pre-volume chamber assembly as described in Chapter 4A. 2 Remove the secondary air injection system front connecting pipe as described in Chapter 4B. 3 Remove the auxiliary drivebelt as described in Chapter 1. Prior to removal, mark the direction of rotation on the belt to ensure the belt is refitted the same way around. 4 Slacken and remove the coolant pump drivebelt pulley retaining bolts whilst retaining the pump shaft with an open-ended spanner. Remove the pulley and discard the bolts; new ones must be used on refitting (see illustrations). 5 Insert a socket and extension bar in through the one of the power steering pump pulley holes and locate it on a pump mounting bolt to prevent rotation. Slacken and remove the pulley retaining bolts and remove the pulley, noting which way around it is fitted (see illustrations). Discard the bolts; new ones must be used on refitting. 6 Disconnect the right-hand cylinder bank knock sensor wiring connector and unclip it from the front of the timing belt cover. 7 Unclip the covers from the front and righthand end of the wiring harness tray which runs across the front of the timing belt cover. Disconnect the wiring connector from the EGR valve and position the wiring harness clear of the timing belt cover then undo the retaining bolts and remove the tray from the belt cover (see illustrations). 8 Slacken and remove the retaining bolts and remove the auxiliary drivebelt tensioner assembly from the right-hand cylinder head (see illustration). 6.5b . . . and remove the pulley from the pump 6.7a Unclip the front . . . 6.7c Undo the retaining bolts and remove the tray from the timing belt cover 6.8 Undo the retaining bolts and remove the auxiliary drivebelt tensioner 3510 Vauxhall/Opel Omega 2.5 and 3.0 litre engine in-car repair procedures 2C•7 9 Slacken and remove the retaining bolts then remove the outer cover from the engine unit along with its seal (see illustration). Refitting 10 Ensure the seal is firmly fixed to the cover prior to refitting. If necessary, glue it in position with a suitable adhesive (Vauxhall recommend the use of adhesive 08 983 341). Refit the cover to the engine and tighten its retaining bolts to the specified torque. 11 Refit the auxiliary drivebelt tensioner and tighten its retaining bolts to the specified torque. 12 Refit the wiring harness tray onto the cover and securely tighten its retaining bolts. Seat the wiring correctly in the tray then clip on the front and right-hand covers. 13 Refit the drivebelt pulleys to the coolant and power steering pump then fit the new retaining bolts. Tighten the pulley bolts to the specified stage 1 torque then angle-tighten through the specified stage 2 and 3 angles. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy. 14 Refit the auxiliary drivebelt as described in Chapter 1 using the mark made prior to removal to ensure the belt is fitted the correct way around. 15 Refit the air injection system pipe and the pre-volume chamber as described in Chapter 4A and 4B. Rear cover Removal 16 Remove the timing belt as described in Section 7. 17 Remove the camshaft sprockets, the timing belt tensioner pulley/upper guide pulley assembly and the lower guide pulley as described in Section 8. 18 Drain the cooling system and remove the coolant pump (see Chapters 1 and 3). 19 Undo the retaining bolts, noting the correct fitted location of the threaded stud, and remove the rear cover from the engine unit (see illustration). Refitting 20 Refit the rear cover to the engine and tighten its retaining bolts and the threaded stud to their specified torque settings. 21 Refit the coolant pump as described in Chapter 3. 22 Refit the guide pulley, tensioner assembly, camshaft sprockets and crankshaft sprocket as described in Section 8 then refit the timing belt as described in Section 7. 23 On completion, refill the cooling system as described in Chapter 1. 7 Timing belt removal and refitting 4 Note: Accurate adjustment of the timing belt requires the use of the following Vauxhall service tools; camshaft sprocket locking tools (KM-800-1 and KM-800-2), crankshaft sprocket locking tool (KM-800-10), timing belt locating wedge (KM-800-30) and a camshaft sprocket timing gauge (KM-800-20) (see illustration). If the belt is to be refitted without the use of the service tools, it is recommended that the belt adjustment is checked at the earliest possible opportunity by a Vauxhall dealer. Note: The timing belt must be removed and refitted with the engine cold. Removal 1 Disconnect the battery negative lead then position No1 cylinder at TDC on its 6.19 Ensure the threaded stud is correctly positioned when refitting the timing belt rear cover 6.9 Removing the timing belt outer cover compression stroke as described in Section 3. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Remove the crankshaft pulley as described in Section 5. 3 Check the camshaft sprocket timing marks are all correctly aligned with the rear cover marks and the crankshaft sprocket timing mark is aligned with the cutout on the oil pump housing. 4 If the Vauxhall service tools are available, fix the service tool (KM-800-10) to the crankshaft sprocket and lock the crankshaft in position by clamping the tool locking arm firmly around the coolant pump flange. Lock the camshafts in position by inserting the service tools making sure the TOP marking on each tool is uppermost; the sprockets on the right-hand cylinder head must be locked with KM-800-1 (tool is stamped with numbers 1 and 2 and handle is coloured red) and the left-hand cylinder head sprockets with KM-800-2 (tool is stamped with numbers 3 and 4 and handle is coloured green) (see illustrations). 7.0 Vauxhall timing belt service tools 1 Timing gauge (KM-800-20) 2 Sprocket locking tool (KM-800-1) 3 Timing belt wedge (KM-800-30) 3510 Vauxhall/Opel Omega 4 Crankshaft locking tool (KM-800-10) 5 Sprocket locking tool (KM-800-2) 2C 2C•8 2.5 and 3.0 litre engine in-car repair procedures 7.4a If the service tools are available, firmly attach the crankshaft locking tool to the sprocket . . . 7.4b . . . and clamp its locking arm firmly around the coolant pump flange 7.4c Insert the locking tools correctly in between the sprockets . . . 7.4d . . . making sure their TOP markings are uppermost 7.5a Slacken the tensioner pulley retaining nut . . . 7.5b . . . then rotate the pulley clockwise, positioning it just before its stop, and secure it by retightening the nut 5 Slacken the timing belt tensioner pulley nut. Using an Allen key fitted to the hexagonal cutout, rotate the tensioner pulley clockwise so it is positioned just before its stop and hold it in position by securely tighten the retaining nut (see illustrations). 6 Slacken the retaining bolts for the timing belt upper and lower guide pulleys (see illustrations). 7 Slide the timing belt off from its sprockets and remove it from the engine. If the new belt is not being fitted straight away and the service tools are not being used, rotate the crankshaft backwards by approximately 60°; this will position the pistons approximately halfway up the bores reducing the risk of the valves contacting the pistons should the camshafts move. 8 Check the timing belt carefully for any signs of uneven wear, splitting or oil contamination, and renew it if there is the slightest doubt about its condition. If the fitting markings on the outside of the original belt are no longer visible the belt must be renewed regardless of its apparent condition (see paragraph 12). If the engine is undergoing an overhaul and has covered 40 000 miles or it was more than 4 years since the original belt was fitted, renew the belt as a matter of course, regardless of its apparent condition (from 1997 onwards the belt renewal interval was increased to 80 000 miles or 8 years). If signs of oil contamination are found, trace the source of the oil leak and rectify it, then wash down the engine timing belt area and all related components to remove all traces of oil. 7.6a Slacken the retaining bolts securing the upper guide pulley . . . 7.6b . . . and lower guide pulley in position then slide the belt off the sprockets 3510 Vauxhall/Opel Omega Refitting Note: There are two different types of timing belt and tensioner assembly available for this engine and it is essential that the timing belt is of the correct type for the tensioner. A modified tensioner assembly and timing belt were fitted as standard to later (1997 on model year) engines, enabling the belt renewal interval on these engines to be extended to 80 000 miles or 8 years. The modified tensioner assembly can be identified by checking the letter stamped on the tensioner pulley/upper guide roller backplate; the original tensioner is marked with D and the modified assembly marking has an E in it (EA or EB) (see illustration 7.15). It is most important to check the tensioner backplate marking before ordering a timing belt since the modified tensioner and belt can also be installed on early (pre 1997 model year) engines to enable the timing belt renewal interval to be extended. See your Vauxhall dealer for further details. 9 On reassembly, thoroughly clean the timing belt sprockets and tensioner/guide pulleys. 10 Check that the crankshaft sprocket timing mark is still aligned with the cutout on the oil pump housing and the camshaft sprocket marks are aligned with the marks on the rear cover (see Section 3) (see illustrations). If the crankshaft was moved back 60°, rotate it back to TDC to bring the marks into alignment. 2.5 and 3.0 litre engine in-car repair procedures 2C•9 7.10a Ensure the right-hand cylinder head camshaft sprocket markings (1 and 2) . . . 7.10b . . . and the left-hand cylinder head camshaft markings (3 and 4) are all correctly aligned with the rear cover cutouts (arrowed) . . . 7.10c . . . and the crankshaft sprocket timing mark is correctly aligned with the oil pump housing cutout (arrowed) 7.13a Align the double line on the timing belt with the crankshaft sprocket timing mark 7.13b If the service tool is available secure the belt in position with the wedge 11 If the special tools are available lock the camshaft sprockets and crankshaft sprocket in position as described in paragraph 4. 12 Examine the fitting marks on the outer face of the timing belt. The arrows on the belt must point in the direction of rotation and the double line on the belt should be aligned with the crankshaft sprocket mark. The four single lines on the belt will then align with the camshaft sprocket timing marks if the belt is correctly installed. 13 Ensure the arrows on the belt are pointing in the correct direction of rotation then align the double line on the belt with the crankshaft sprocket timing mark and engage the belt with the sprocket. If the locating wedge (KM800-30) is available secure the belt in position by inserting the wedge in between the righthand side of the belt and the rear cover (see illustrations). 14 Check the identification marking stamped onto the tensioner pulley/upper guide pulley backplate (see Note at the start of the refitting procedure). 15 On early engines with the original tensioner (marked with a D - see illustration), fit the timing belt over the lower guide pulley then around the left-hand cylinder head camshaft sprockets making sure the belt fitting marks are correctly aligned with the sprocket marks. Fit the belt around the upper guide pulley then over the right-hand cylinder camshaft, again making sure the fitting marks are correctly aligned and tensioner pulley. Do not twist the belt sharply while refitting it. 16 On all engines fitted with the modified tensioner (marked with an E - see illustration 7.15), fit the belt behind the tensioner pulley and then over the right-hand cylinder head camshaft sprockets ensuring that the fitting marks are both correctly aligned with the sprocket marks. Fit the belt around the upper guide pulley then over the left-hand cylinder camshaft sprockets, again making sure the fitting marks are correctly aligned, and finally over the lower guide pulley (see illustrations). Do not twist the belt sharply while refitting it. 7.15 Checking the marking (location arrowed) on the tensioner/upper guide pulley backplate to identify which type of tensioner assembly is fitted to your engine - see text 7.16a On engines with a modified tensioner, work around in a clockwise direction and engage the belt first with the right-hand cylinder head sprockets . . . 3510 Vauxhall/Opel Omega 2C 2C•10 2.5 and 3.0 litre engine in-car repair procedures 7.16b . . . and then the left-hand head sprockets (directional fitting arrows arrowed), making sure the fitting lines are all correctly aligned with the sprockets . . . 17 On all engines, ensure that the belt teeth are correctly seated centrally in the sprockets and the sprocket timing marks/belt fitting marks are correctly aligned. If adjustment is necessary, disengage the belt from the sprockets and make any necessary adjustments. 7.18a Remove all slack from the left-hand run of the belt by rotating the lower guide pulley whilst making sure the sprocket timing marks remain in alignment (timing gauge shown) . . . 7.18b . . . then hold the pulley stationary and tighten its retaining bolt to the specified torque 7.16c . . . and finally over the lower guide pulley 18 Slacken the lower guide pulley retaining bolt. Rotate the pulley anti-clockwise to remove all slack from the left-hand run of the belt without placing any excess strain on the belt. Ensure that all the sprocket timing marks remain in alignment as the pulley is moved; if the service tools are available, remove the locking tools and use the timing gauge (KM800-20) to check the sprocket mark positions. Once the pulley is correctly positioned, hold it stationary and tighten its retaining bolt to the specified torque (see illustrations). 19 Slacken the upper guide pulley retaining bolt. Rotate the pulley anti-clockwise to remove all slack from the top run of the belt without placing any excess strain on the belt. Ensure that all the sprocket timing marks remain in alignment as the pulley is moved. Once the pulley is correctly positioned, hold it stationary and tighten its retaining bolt to the specified torque (see illustration). 20 Slacken the timing belt tensioner pulley nut then, using an Allen key, rotate the tensioner arm anti-clockwise until the gap between the tensioner plate and its stop is 0.5 to 1.5 mm (see illustration). Hold the tensioner pulley in this position and securely tighten its retaining nut. 21 Remove all the service tools (where fitted) then using a socket on the crankshaft sprocket bolt, rotate the crankshaft smoothly through two complete turns (720°) in the normal direction of rotation to settle the timing belt in position. 22 Check that all the camshaft and crankshaft sprocket timing marks are correctly realigned then slacken the tensioner nut again. Note: The belt fitting lines will not be realigned with the sprocket marks; they serve no purpose once the belt has been installed. 23 Using an Allen key, position the tensioner pulley so that the index mark on the tensioner plate is positioned 3 to 4 mm above the mark on the backplate stop (see illustration). Hold the tensioner correctly in position and tighten its retaining nut to the specified torque. 24 Rotate the crankshaft smoothly through 7.19 Remove all slack from the top run of the belt then hold the upper pulley stationary and tighten its retaining bolt to the specified torque 7.20 Rotate the tensioner pulley anticlockwise until the gap (arrowed) is 0.5 to 1.5 mm then securely tighten its retaining nut 3510 Vauxhall/Opel Omega 2.5 and 3.0 litre engine in-car repair procedures 2C•11 7.23 Adjust the tensioner pulley so that its index mark (A) is positioned 3 to 4 mm above backplate mark (B) then tighten its retaining nut to the specified torque another two complete turns (720°) in the normal direction of rotation to bring the sprocket timing marks back into alignment. 25 If the service tools are available, lock the crankshaft in position (KM-800-10) and check the camshaft sprocket timing marks are correctly positioned using the timing gauge (KM-800-20). 26 If the service tools are not available, ensure the crankshaft sprocket timing mark is correctly aligned with the cutout on the oil pump housing and all the camshaft sprocket timing marks are exactly aligned with the cutouts on the rear cover. 27 If adjustment is necessary repeat the operations described in paragraphs 18 to 26. 28 Once the timing marks are all correctly aligned, refit the timing belt cover and crankshaft pulley as described in Sections 5 and 6. Note: If refitting has been carried out without the use of the service tools, it is advisable to have the belt adjustment checked by a Vauxhall dealer at the earliest possible opportunity. 8.2b If the camshaft cover has been removed, the camshaft can be held with an open-ended spanner on the flats provided 8.2a Using a home-made tool to prevent rotation as the camshaft sprocket bolt is slackened 8 Timing belt sprockets, tensioner and guide pulleys removal and refitting 4 Camshaft sprockets Note: New sprocket retaining bolt(s) will be required on refitting. Removal 1 Remove the timing belt as described in Section 7. Once the belt has been removed, rotate the crankshaft backwards by approximately 60°; this will position the pistons approximately halfway up the bores reducing the risk of the valves contacting the pistons. 2 The camshaft must be prevented from turning as the sprocket bolt is unscrewed, and this can be achieved in one of two ways. a) Make up a sprocket-holding tool using two lengths of steel strip (one long, the other short), and three nuts and bolts; one 8.3a Unscrew the retaining bolt and washer . . . 3510 Vauxhall/Opel Omega nut and bolt forms the pivot of a forked tool, with the remaining two nuts and bolts at the tips of the ‘forks’ to engage with the sprocket spokes (see illustration). b) Remove the camshaft cover as described in Section 4 and hold the camshaft with an open-ended spanner on the flats provided (see illustration). 3 Unscrew the retaining bolt and washer and remove the sprocket from the end of the camshaft (see illustrations). If the sprocket locating pin is a loose fit in the camshaft end, remove it and store it with the sprocket for safe-keeping. 4 If necessary, remove the remaining sprocket(s) using the same method. Refitting 5 Prior to refitting check the oil seal(s) for signs of damage or leakage. If necessary, renew as described in Section 9. 6 Ensure the locating pin is in position in the camshaft end. 8.3b . . . and remove the sprocket from the camshaft 2C 2C•12 2.5 and 3.0 litre engine in-car repair procedures 8.7a Right-hand cylinder head camshaft sprocket. Ensure timing mark and slot 1 are used on the exhaust camshaft and 2 on the inlet camshaft 8.7b Left-hand cylinder head camshaft sprocket. Ensure timing mark and slot 3 are used on the inlet camshaft and 4 on the exhaust camshaft 8.8a Ensure the locating pins are engaged in the correct sprocket slots (arrowed) . . . 8.8b . . . and the relevant sprocket timing marks are correctly aligned with the rear cover cutouts (arrowed) 7 Note that there are two pairs of camshaft sprockets, one for the right-hand cylinder head and the other for the left-hand cylinder head; the right-hand cylinder head sprockets carry the identification marks 1 and 2 and the left-hand cylinder head sprockets the marks 3 and 4. The inlet and exhaust camshaft sprockets on each head are the same but each one is equipped with two locating pin cutouts and two timing marks. On refitting is vital that the sprocket locating pin is engaged in the correct sprocket slot as follows and the correct timing mark is used (see illustrations). 8.9a Retaining the sprocket/camshaft then tighten the retaining bolt first to the stage 1 torque . . . 8.9b . . . and then through the specified stage 2 and 3 angles 3510 Vauxhall/Opel Omega Camshaft Sprocket slot/timing mark number to be used Right-hand cylinder head exhaust 1 Right-hand cylinder head inlet 2 Left-hand cylinder head inlet 3 Left-hand cylinder head exhaust 4 8 Ensure the camshaft locating pin is engaged in the correct sprocket cutout then fit the washer and new retaining bolt (see illustrations). 9 Retain the sprocket by the method used on removal, and tighten the sprocket retaining bolt to the specified stage 1 torque setting then angle-tighten the bolt through the specified stage 2 angle, using a socket and extension bar, and finally through the specified stage 3 angle (see illustrations). It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy. If a gauge is not available, use white paint to make alignment marks between the bolt head and sprocket prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 2.5 and 3.0 litre engine in-car repair procedures 2C•13 8.13 Home-made tool for preventing crankshaft rotation as the sprocket bolt is slackened 8.14a Unscrew the retaining bolt . . . 10 Ensure the relevant camshaft sprocket timing marks are all correctly aligned with the cutouts on the rear cover then carefully rotate the crankshaft in the normal direction of rotation until the sprocket mark is correctly realigned with the notch on the oil pump housing. 11 Refit the timing belt as described in Section 7 then (where necessary) refit the camshaft cover as described in Section 4. crankshaft. Discard the bolt; a new one must be used on refitting. If necessary, slide the spacer out from the oil seal and remove it from the crankshaft; if the outer surface of the spacer is damaged it should be renewed (see illustrations). Refitting 12 Remove the timing belt as described in Section 7. 13 The crankshaft must be prevented from turning as the sprocket bolt is unscrewed (the bolt is very tight), and this can be achieved in anyone of the following ways. a) Use the holding tool described in paragraph 2 securing the tool to the sprocket with two bolts screwed into opposite pulley retaining bolt holes (see illustration). b) On manual transmission models have an assistant select top gear and apply the brakes firmly. c) If the engine is removed from the vehicle or the transmission unit has been removed the flywheel/driveplate can be locked (see Section 15). 14 Unscrew the retaining bolt and remove the crankshaft sprocket from the end of the 15 Prior to refitting, examine the oil seal for signs of damage or deterioration and renew if necessary (see Section 16). 16 Slide the spacer (where removed) onto the crankshaft and into position taking care not to damage the oil seal lip. 17 Align the sprocket with the crankshaft slot and slide it into position, ensuring the sprocket flange is facing outwards. Fit the new retaining bolt. 18 Lock the crankshaft by the method used on removal, and tighten the sprocket retaining bolt to the specified stage 1 torque setting then angle-tighten the bolt through the specified stage 2 angle, using a socket and extension bar, and finally through the specified stage 3 angle. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy (see illustrations). If a gauge is not available, use white paint to make alignment marks between the bolt head and sprocket prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 19 Refit the timing belt as described in Section 7. 8.18a Tighten the crankshaft sprocket bolt to the specified stage 1 torque setting . . . 8.18b . . . then tighten it through the specified stage 2 and 3 angles Crankshaft sprocket Note: A new crankshaft sprocket retaining bolt will be required on refitting. Removal 8.14b . . . then slide off the crankshaft sprocket . . . 3510 Vauxhall/Opel Omega 8.14c . . . and, if necessary, withdraw the spacer from the oil seal Tensioner pulley/ upper guide pulley assembly Note: The tensioner pulley/upper guide pulley assembly must be renewed as a complete unit. It is not possible to renew the individual components of the assembly separately. Removal 20 Remove the timing belt as described in Section 7. 21 Slacken and remove the retaining bolts securing the backplate to the cylinder head and remove the assembly from the engine (see illustrations). Refitting 22 Fit the tensioner pulley/upper guide pulley assembly to the cylinder head and tighten its retaining bolts to the specified torque. 8.21a Undo the retaining bolts (arrowed) . . . 2C 2C•14 2.5 and 3.0 litre engine in-car repair procedures 9.2a Carefully drill/punch holes in the oil seal . . . 1 Remove the camshaft cover as described in Section 4. 2 Remove the camshaft sprockets as described in Section 8. If the right-hand cylinder head camshafts are to be removed, rotate both the inlet and exhaust camshaft backwards approximately 60°; this will minimise the valve spring pressure being exerted on the bearing caps and so lessen the risk of damage as the caps are removed. The left-hand cylinder head camshafts are best left positioned at TDC. 3 Starting on the inlet camshaft, working in a spiral pattern from the outside inwards, slacken the camshaft bearing cap retaining bolts by half-a-turn at a time, to relieve the pressure of the valve springs on the bearing caps gradually and evenly. Once the valve spring pressure has been relieved, the bolts can be fully unscrewed and removed along with the caps. The bearing caps and the cylinder head locations are numbered to ensure the caps are correctly positioned on refitting; an identification letter is also stamped on each cap (see illustration). Caution: If the bearing cap bolts are carelessly slackened, the bearing caps might break. If any bearing cap breaks then the complete cylinder head assembly must be renewed; the bearing caps are matched to the head and are not available separately. 4 Lift the camshaft out of the cylinder head and slide off the oil seal. Using a dab of paint or a suitable marker pen, make an identification mark on the inlet camshaft to avoid getting the camshafts mixed up on refitting; the inlet and exhaust camshafts are the same but it is important they are not interchanged as this will increase the rate of wear. 5 Repeat the operations described in paragraphs 3 and 4 and remove the exhaust camshaft. If the work is being carried out on the left-hand cylinder head, prior to removing the bearing caps, unbolt the camshaft sensor (see Chapter 4A, Section 14) and position it clear of the front bearing cap and free the knock sensor wiring. 6 Obtain twelve small, clean plastic containers, and label them for identification. Alternatively, divide a larger container into compartments. Lift the followers out from the 9.2b . . . then screw in a self-tapping screw and pull out the oil seal with pliers/grips 9.4 Tap the new seal into position using a socket which bears only on the seal outer edge as a drift 10.3 Prior to removal note the identification markings on the camshaft caps and cylinder head (arrowed) 8.21b . . . and remove the tensioner pulley/upper guide pulley assembly from the cylinder head 23 Refit the timing belt as described in Section 7. If a new tensioner assembly has been fitted, fit a new timing belt ensuring it is of the correct type for the tensioner. Lower guide pulley Removal 24 Remove the timing belt as described in Section 7. 25 Slacken and remove the retaining bolt and remove the lower guide pulley and its spacer from the engine (see illustration). Refitting 26 Position the spacer behind the guide pulley then refit the pulley retaining bolt, tightening it lightly only at this stage. 27 Refit the timing belt as described in Section 7. 8.25 Unscrew the retaining bolt and remove the lower guide pulley and its spacer (arrowed) from the engine 9 Camshaft oil seals renewal 4 1 Remove the relevant camshaft sprocket as described in Section 8. 2 Carefully punch or drill two small holes opposite each other in the oil seal. Screw a self-tapping screw into each, and pull on the screws with pliers to extract the seal (see illustrations). Alternatively carefully lever the oil seal out of position. 3 Clean the seal housing, and polish off any burrs or raised edges which may have caused the seal to fail in the first place. 4 Lubricate the lips of the new seal with clean engine oil, and press it into position using a suitable tubular drift (such as a socket) which bears only on the hard outer edge of the seal (see illustration). Take care not to damage the seal lips during fitting; note that the seal lips should face inwards. 5 Refit the camshaft sprocket as described in Section 8. 10 Camshafts and followers removal, inspection and refitting 4 Removal 3510 Vauxhall/Opel Omega 2.5 and 3.0 litre engine in-car repair procedures 2C•15 10.6 Removing a camshaft follower 10.11a Lay the camshafts in position . . . 10.11b . . . then temporarily refit the sprockets to position the shafts correctly (see text) top of the cylinder head and store each one in its respective fitted position (see illustration). Note: Store all the followers the correct way up to prevent the oil draining from the hydraulic valve adjustment mechanisms. 7 If necessary, repeat the operations described in paragraphs 1 to 6 and remove the camshafts and followers from the other cylinder head. If all the camshafts are to be removed at the same time, make identification marks on the shafts to ensure they are refitted in their original locations, and note the camshaft bearing caps identification letter locations to ensure the caps are refitted to the correct cylinder head. 10 Where removed, lubricate the followers with clean engine oil and carefully insert each one into its original location in the cylinder head. 11 Lubricate the camshaft followers with clean engine oil then lay the camshafts in position. Ensure the crankshaft is still positioned approximately 60° BTDC then temporarily refit the sprockets (see Section 8 for details) to the camshafts (see illustrations). On the left-hand cylinder head position each shaft so that its sprocket timing mark is aligned with cutouts on the rear cover and on the right-hand cylinder head position each shaft so that its sprocket timing mark is approximately 60∞ before the rear cover cutouts. This will position each camshaft so that the valve spring pressure will be equally exerted along its length as the bearing caps are tightened. 12 Ensure the mating surfaces of the bearing caps and cylinder head are clean and dry and lubricate the camshaft journals and lobes with clean engine oil. 13 Apply a smear of sealant (Vauxhall recommend the use of sealant 15 03 170 available from your Vauxhall dealer) to cylinder mating surfaces on each side of the camshaft oil seal apertures (see illustration). 14 Refit the camshaft bearing caps and the retaining bolts in their original locations on the cylinder head. The exhaust camshaft caps are numbered 1 to 4 from front to rear and the inlet camshaft caps 5 to 8 from front to rear with the corresponding numbers being marked on the cylinder head upper surface (see illustration). 15 Working on the exhaust camshaft, tighten the bearing cap bolts by hand only then, working in a spiral pattern from the centre outwards, tighten the bolts by half-a-turn at a time to gradually impose the pressure of the valve springs on the bearing caps. Repeat this sequence until all bearing caps are in contact with the cylinder head then go around and tighten the camshaft retaining bolts to the specified torque (see illustration). Caution: If the bearing cap bolts are carelessly tightened, the bearing caps might break. If any bearing cap breaks then the complete cylinder head assembly must be renewed; the bearing caps are matched to the head and are not available separately. 16 Tighten the inlet camshaft bearing cap bolts as described in paragraph 15. 17 If necessary, repeat the operations in paragraphs 10 to 15 and refit the camshafts to the opposite cylinder head. 18 Fit new camshaft oil seals as described in Section 9. 19 Refit the camshaft sprockets as described in Section 8. 20 Ensure the camshaft sprocket timing marks are all correctly aligned with the cutouts on the rear cover then carefully rotate the crankshaft in the normal direction of rotation until the sprocket mark is correctly realigned with the notch on the oil pump housing. 21 Refit the timing belt as described in Section 7. 22 Refit the camshaft cover(s) and timing belt cover as described in Sections 4 and 6. 10.13 Apply sealant to the cylinder head surface on each side of the camshaft oil seal apertures (arrowed) 10.14 Use the identification markings (arrowed) to ensure that the bearing caps are refitted in their original locations 10.15 Carefully tighten the camshaft bearing cap bolts as described in text Inspection 8 Examine the camshaft bearing surfaces and cam lobes for signs of wear ridges and scoring. Renew the camshaft if any of these conditions are apparent. Examine the condition of the bearing surfaces both on the camshaft journals and in the cylinder head. If the head bearing surfaces are worn excessively, the cylinder head will need to be renewed. 9 Examine the follower bearing surfaces which contact the camshaft lobes for wear ridges and scoring. Check the followers and their bores in the cylinder head for signs of wear or damage. If any follower is thought to be faulty or is visibly worn it should be renewed. Refitting 3510 Vauxhall/Opel Omega 2C 2C•16 2.5 and 3.0 litre engine in-car repair procedures 11.5 Disconnect the wiring connectors (arrowed) from the coolant temperature sender and sensor . . . 11.6 . . . then release the retaining clips and disconnect the coolant hoses from the outlet elbow 11.7 Unscrew the retaining bolts then remove the coolant outlet elbow from between the cylinder heads and recover the sealing washers (arrowed) 3 Remove the complete inlet manifold assembly, including the manifold flange, as described in Chapter 4A. 4 Drain the cooling system and remove the spark plugs as described in Chapter 1. 5 Disconnect the wiring connectors from the coolant temperature gauge sender and the engine management system coolant temperature sensor which are screwed into the coolant outlet which links the rear of the cylinder heads (see illustration). 6 Slacken the retaining clips and disconnect the coolant hoses from the cylinder head outlet (see illustration). 7 Unscrew the retaining bolts and remove the coolant outlet from the cylinder heads. Recover the sealing rings and discard them; new ones must be used on refitting (see illustration). 8 Remove the timing belt as described in Section 7. 9 Remove the camshaft sprockets, the timing belt tensioner pulley/upper guide pulley assembly and the lower guide pulley as described in Section 8. 10 Remove the coolant pump as described in Chapter 3. 11 Undo the retaining bolts and remove the timing belt rear cover from the engine unit (see Section 6). Proceed as described under the relevant sub-heading. 11.14 Disconnecting the wiring connector from the engine management ECU 12 Remove the camshaft cover as described in Section 4. 13 Disconnect the wiring connector and the right-hand cylinder head plug leads from the DIS module so the module is free to be removed with the head. Also unbolt the earth connections from the rear of the left-hand cylinder head. 14 Remove the cover from the relay box in the left-hand corner of the engine compartment. Lift out the engine management electronic control unit (ECU) then release the retaining clip and disconnect its wiring connector (see Chapter 4A, Section 14) (see illustration). The ECU can be left in position in the box. 15 Trace the engine wiring harness back from the left-hand cylinder head to the engine compartment relay box. Unclip the injection system relay connectors from the box then disconnect the harness connector and free the sealing grommet from the relay box (see illustrations). 16 Disconnect the harness connectors which are located at the rear of the battery then disconnect the camshaft sensor and left-hand cylinder bank knock sensor wiring connectors. Free the engine wiring harness auxiliary connections from the battery positive terminal and position the harness clear of the cylinder head. On some models the harness is connected to the fusible link housing instead of the battery terminal; where this is the case, remove the fusible link and unclip the connector from the housing (see illustrations). 17 Remove the exhaust system left-hand front pipe as described in Chapter 4A. 11.15a Unclip the injection system relays . . . 11.15b . . . then disconnect the wiring connector . . . 11.15c . . . and free the wiring harness from the relay box 11 Cylinder head removal and refitting 4 Removal Note: The engine must be cold when removing the cylinder head. New cylinder head bolts must be used on refitting. 1 Remove the battery as described in Chapter 5A. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Remove the windscreen wiper arms and the water deflector panel (see Chapter 12, Sections 15 and 16). Left-hand cylinder head 3510 Vauxhall/Opel Omega 2.5 and 3.0 litre engine in-car repair procedures 2C•17 11.16a Disconnect the harness connectors located at the rear of the battery 11.16b Where the engine harness is connected to the fusible link housing, remove the fusible link . . . 18 Remove the power steering pump as described in Chapter 10. 19 Slacken the retaining clip and disconnect the radiator upper coolant hose from the pipe at the front of the left-hand cylinder head. 20 Unscrew the bolt and spacer securing the coolant pipe and engine lifting bracket to the cylinder head and remove the lifting bracket. Move the coolant pipe to the left to free it from the thermostat housing then manoeuvre it out of position (see illustrations). Remove the sealing rings from the inner end of the pipe and discard them; new ones must be used on refitting. 21 Remove the dipstick then free the dipstick tube from the cylinder block and remove it from the engine. Discard the tube sealing rings; new ones should be used on refitting. 22 Remove the exhaust camshaft as described in Section 10. 23 Working in the reverse of the tightening sequence (see illustration 11.41a), progressively slacken the cylinder head bolts by a quarter of a turn at a time until all bolts can be unscrewed by hand (see illustration). Remove each bolt in turn, along with its washer. 24 Lift the cylinder head from the cylinder block (see illustration). If necessary, tap the cylinder head gently with a soft-faced mallet to free it from the block, but do not lever at the mating faces. Note the fitted positions of the two locating dowels, and remove them for safe keeping if they are loose. 25 Recover the cylinder head gasket, and discard it. 11.16c . . . then unclip the connector from the housing 11.16d Once all the wiring has been disconnected, position the harness clear of the cylinder head 11.20a Slacken and remove the retaining bolt and spacer . . . 11.20b . . . then remove the coolant pipe from the thermostat housing (shown with engine removed) removal tool if necessary, and drain the oil into the container. If the oil filter is damaged or distorted during removal, it must be renewed. Given the low cost of a new oil filter relative to the cost of repairing the damage which could result if a re-used filter springs a leak, it is probably a good idea to renew the filter in any case. 27 Unscrew the union nuts securing the oil cooler pipes to the cylinder block then unscrew the union bolts securing the pipes to the cooler. Recover the sealing washers from each side of the oil cooler unions and move the pipes to the rear (see illustrations). 28 Release the retaining clips and disconnect the radiator bottom hose, expansion tank hose and heater hose from the coolant pipe which runs along the right-hand side of the engine. Slacken and remove the retaining bolts then remove the pipe from the engine. 11.23 Evenly and progressively slacken and remove the cylinder head bolts . . . 11.24 . . . then lift the cylinder head off the block 11.27a Unscrew the union nuts (arrowed) securing the oil pipes to the cylinder block . . . Right-hand cylinder head 26 Position a suitable container beneath the oil filter. Unscrew the filter using an oil filter 3510 Vauxhall/Opel Omega 2C 2C•18 2.5 and 3.0 litre engine in-car repair procedures 11.27b . . . then remove the union bolts and sealing washers (arrowed) and free the pipes from the oil cooler 11.28a Disconnect the expansion tank hose . . . Recover the sealing ring and discard it; a new one should be used on refitting (see illustrations). 29 Remove the exhaust system right-hand front pipe as described in Chapter 4A. 30 Remove the exhaust camshaft as described in Section 10. 31 Remove the cylinder head as described in paragraphs 23 to 25 (see illustration). with a cloth rag. Clean the piston crowns in the same way. 33 Check the block and head for nicks, deep scratches and other damage. If slight, they may be removed carefully with a file. More serious damage may be repaired by machining, but this is a specialist job. 34 If warpage of the cylinder head is suspected, use a straight-edge to check it for distortion. Refer to Chapter 2D if necessary. 35 Ensure that the cylinder head bolt holes in the crankcase are clean and free of oil. Syringe or soak up any oil left in the bolt holes. This is most important in order that the correct bolt tightening torque can be applied and to prevent the possibility of the block being cracked by hydraulic pressure when the bolts are tightened. Renew the cylinder head bolts regardless of their apparent condition. Preparation for refitting 32 The mating faces of the cylinder head and block must be perfectly clean before refitting the head. Use a scraper to remove all traces of gasket and carbon, and also clean the tops of the pistons. Take particular care with the aluminium surfaces, as the soft metal is damaged easily. Also, make sure that debris is not allowed to enter the oil and water channels - this is particularly important for the oil circuit, as carbon could block the oil supply to the camshaft or crankshaft bearings. Using adhesive tape and paper, seal the water, oil and bolt holes in the cylinder block. To prevent carbon entering the gap between the pistons and bores, smear a little grease in the gap. After cleaning the piston, rotate the crankshaft so that the piston moves down the bore, then wipe out the grease and carbon Refitting Left-hand cylinder head 36 Ensure the crankshaft is till positioned approximately 60° BTDC and wipe clean the mating faces of the head and block. 37 Ensure that the two locating dowels are in position at each end of the cylinder block/crankcase surface. 11.31 Removing the right-hand cylinder head assembly 11.28b . . . and heater hose (arrowed) from the coolant pipe . . . 11.28c . . . then undo the retaining bolts and remove the pipe from the engine 38 Fit the new cylinder head gasket to the block, making sure it is fitted with the correct way up with its OBEN or TOP mark uppermost and at the front end of the engine (see illustration). 39 Carefully refit the cylinder head (complete with exhaust manifold), locating it on the dowels. 40 Lightly lubricate the threads and heads of the new cylinder head bolts with engine oil then carefully insert them into position (do not drop), tightening them finger-tight only at this stage. 11.38 Ensure the locating dowels (arrowed) are in position then fit the new head gasket 3510 Vauxhall/Opel Omega 2.5 and 3.0 litre engine in-car repair procedures 2C•19 11.41a Cylinder head bolt tightening sequence (left-hand head shown) 41 Working progressively and in the sequence shown, first tighten all the cylinder head bolts to the stage 1 torque setting (see illustrations). 42 Once all bolts have been tightened to the stage 1 torque, again working in the sequence shown, tighten each bolt through its specified stage 2 angle, using a socket and extension bar. It is recommended that an anglemeasuring gauge is used during this stage of the tightening, to ensure accuracy (see illustration). 43 Working in the specified sequence, go around again and tighten all bolts through the specified stage 3 angle. 44 Working again in the specified sequence, go around and tighten all bolts through the specified stage 4 angle. 45 Finally go around in the specified sequence again and tighten all bolts through the specified stage 5 angle. 46 The remainder of the refitting procedure is the reverse of removal noting the following points a) If the right-hand cylinder head has also been removed, refit this to the block before connecting any ancillaries. b) Fit new sealing rings to the dipstick tube and thermostat housing coolant pipe. Ensure the coolant pipe, dipstick tube and lifting bracket are correctly positioned before refitting the retaining bolt and spacer and tightening to the specified torque. c) Ensure the engine wiring harness is correctly routed and securely reconnect all the wiring connectors. Also make sure the earth lead retaining bolts are securely tightened. d) Refit the camshaft, timing belt and associated components as described in Sections 6 to 10. e) Use new sealing rings when refitting the coolant outlet to the cylinder heads and 11.41b Working in the specified sequence, tighten the cylinder head bolts to the specified stage 1 torque . . . tighten the retaining bolts to the specified torque. f) Ensure all coolant hoses are correctly reconnected and securely retained by their clips. g) Refit the exhaust front pipe and inlet manifold as described in Chapter 4A. h) On completion refill the cooling system and power steering fluid reservoir (see Chapter 1 and Weekly checks). Right-hand cylinder head 47 Refit the cylinder head as described in paragraphs 36 to 45 noting that the cylinder head gasket OBEN or TOP mark must be uppermost and at the rear end of the engine. 48 The remainder of the refitting procedure is the reverse of removal noting the following points a) If the left-hand cylinder head has also been removed, refit this to the block before connecting any ancillaries. b) Fit a new sealing ring to coolant pipe and securely tighten the pipe retaining bolts. c) Fit new sealing washers to each side of the oil cooler pipe unions and tighten the pipe union nuts and bolts to the specified torque. 11.42 . . . and then through the specified stage 2 to 5 angles using an angle measuring gauge for accuracy 3510 Vauxhall/Opel Omega d) Refit the camshaft, timing belt and associated components as described in Sections 6 to 10. e) Use new sealing rings when refitting the coolant outlet to the cylinder heads and tighten the retaining bolts to the specified torque. f) Ensure all coolant hoses are correctly reconnected and securely retained by their clips. g) Refit the exhaust front pipe and inlet manifold as described in Chapter 4A. h) Fit a new oil filter and refill the cooling system as described in Chapter 1. i) On completion, check the engine oil level as described in Weekly checks. 12 Sump removal and refitting 4 Removal Sump pan Note: New sump pan retaining bolts will be required on refitting. 1 Disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Firmly apply the handbrake then jack up the front of the car and support it on axle stands. Undo the retaining screws and remove the undercover from beneath the engine. 3 Drain the engine oil as described in Chapter 1, then fit a new sealing washer and refit the drain plug, tightening it to the specified torque. 4 Disconnect the wiring connector from the oil level sensor connector on the right-hand 2C 2C•20 2.5 and 3.0 litre engine in-car repair procedures 12.4 Slide off the retaining clip and push the oil level sensor wiring connector into the sump 12.16 Fit a new sealing ring to the oil pump pick-up/strainer before refitting 12.18 On refitting, locate the oil level sensor wiring connector in the main casting before bolting the sump pan in position side of the main casting then slide off the retaining clip and push the connector into the sump (see illustration). 5 Slacken and remove the sump pan retaining bolts then free it from the main casting and remove it along with its gasket. Take care not to damage the oil level sensor wiring as the pan is removed. 6 If necessary, undo the retaining bolts (one is tricky to reach) and remove the oil pump pick-up/strainer from the base of the oil pump housing along with its sealing ring. Check the oil pump pick-up/strainer for signs of clogging or splitting and renew/clean as necessary. 12 Attach an engine hoist to the engine lifting brackets then raise the hoist until it is supporting the weight of the engine. Alternatively use an engine support bar to take the weight of the engine. 13 Referring to Chapter 10, unscrew the front suspension subframe front mounting bolts by approximately 4 turns. Support the rear of the subframe with a jack then slacken and remove the rear mounting bolts. Lower the rear of the subframe approximately 10 cm to gain access to the main casting. 14 Unscrew the bolts securing the main casting flange to the transmission housing then progressively slacken and remove the bolts securing the main casting to the base of the cylinder block/oil pump. Break the joint by striking the casting with the palm of the hand, then lower it away from the engine and withdraw it. Remove the seal and discard it. Note: If the main casting is to be removed for any length of time, raise the subframe back up into position and refit its mounting bolts then lower the engine back down onto the subframe. then refit the strainer, tightening its retaining bolts to the specified torque (see illustration). 17 Ensure the sump pan and main casting surfaces are clean and dry and fit a new sealing ring to the oil level sensor wiring connector. 18 Place a new gasket on the top of the pan and offer it up to the main casting. Seat the oil level sensor wiring connector in the main casting, securing it in position with the retaining clip, then seat the sump pan on the main casting (see illustration). 19 Fit the new sump pan retaining bolts then go around in a diagonal sequence and tighten them to the specified stage 1 torque setting. Once all bolts have been tightened go around again and angle-tighten them through the specified stage 2 angle. It is recommended that an angle-measuring gauge is used during this stage of the tightening, to ensure accuracy. 20 Reconnect the oil level sender wiring connector then refit the undercover. 21 Lower the vehicle to the ground then fill the engine with fresh oil, with reference to Chapter 1. Main casting Note: New front suspension subframe mounting bolts will be required on refitting. New retaining nuts for the centre tie rod will also be required. 7 Remove the sump pan and oil pickup/strainer as described in paragraphs 1 to 6. 8 Referring to Chapter 12, on models with Xenon headlights, disconnect the wiring connector from the headlight system front vehicle level control sensor then unclip the link rod from the sensor arm balljoint. 9 Remove the steering linkage centre tie rod as described in Chapter 10, Section 25. 10 Slacken and remove the mounting bolts and remove the vibration dampers from the left- and right-hand engine mountings 11 Slacken and remove the nuts securing the engine left- and right-hand mountings to the subframe. 12.23 Apply a bead of sealant (arrowed) to the main casting seal groove in between the lines shown . . . Refitting Sump pan 15 Remove all traces of dirt and oil from the mating surfaces of the sump pan, main casting and (if necessary) the pick-up/strainer and oil pump housing. 16 Where necessary, position a new sealing ring on top of the oil pump pick-up/strainer 12.24a . . . then locate the new seal in the casting groove 3510 Vauxhall/Opel Omega Main casting 22 Remove all traces of dirt and oil from the mating surfaces of the main casting and cylinder block. 23 Ensure the main casting seal groove is completely dry then apply a bead of sealant (Vauxhall recommend the use of sealant 15 03 298 - available from your Vauxhall dealer) to the areas of the groove shown (see illustration). Note: If the Vauxhall sealant is being used, the main casting must be bolted in position on the cylinder block within ten minutes of applying the sealant. 24 Locate the new seal correctly in its groove then apply a bead of the sealant, approximately 3mm in diameter, to the main casting surface as shown (see illustrations). The sealant should go around the outside of the seal around the front of the casting and the inside at the rear, making sure the sealant overlaps at the points shown. 25 Apply a smear of suitable sealant (Vauxhall recommend the use of sealant 15 03 295 available from your Vauxhall dealer) to the areas of the cylinder block mating surface 2.5 and 3.0 litre engine in-car repair procedures 2C•21 around the areas of the oil pump housing and rear main bearing cap joints (see illustrations). 26 Manoeuvre the casting into position and loosely refit all its retaining bolts. 27 Working out from the centre in a diagonal sequence, progressively tighten the bolts securing the main casting to the cylinder block/oil pump to their specified torque setting. 28 Tighten the bolts securing the casting flange to the transmission housing to their specified torque settings. 29 Raise the subframe back up into position making sure the engine mounting lugs engage correctly with the subframe cutouts. Fit the four new rear retaining bolts then remove the subframe front retaining bolts and fit the new ones. Tighten the subframe mounting bolts to their specified torque setting and then through the specified angles as described in Chapter 10. 30 Remove the hoist/support bar from the engine then refit the nuts securing the engine mountings to the subframe, tightening them to the specified torque. Refit the vibration dampers to the mountings and tighten their mounting bolts to the specified torque. 31 Refit the steering linkage centre tie rod as described in Chapter 10 32 On models with Xenon headlights clip the link rod balljoint back onto the vehicle level control sensor and reconnect the wiring connector (see Chapter 12). 33 Refit the sump pan as described in paragraphs 15 to 21. 13 Oil pump removal, overhaul and refitting 2C 4 Removal 1 Remove the timing belt as described in Section 7. 2 Remove all the camshaft sprockets, the crankshaft sprocket, the belt tensioner pulley/upper guide pulley assembly and the lower guide pulley as described in Section 8. 3 Undo the retaining bolts and remove the rear timing belt cover from the front of the engine (see Section 6). 4 Remove the sump pan, oil pump pickup/strainer and main casting as described in Section 12. 5 Slacken and remove the alternator lower mounting bolt then slacken the upper bolt and pivot the alternator clear of the oil pump housing. 6 Disconnect the wiring connector from the oil pressure switch then unscrew the bolt securing the wiring guide to the front of the pump housing. 7 Slacken and remove the retaining bolts then slide the oil pump housing assembly off of the end of the crankshaft, taking great care not to lose the locating dowels. Remove the housing gasket and discard it. 12.24b Apply beads of sealant to the main casting mating surface as shown 12.25a Apply a smear of sealant to the joints between the oil pump housing and cylinder block . . . 3510 Vauxhall/Opel Omega 12.25b . . . and the rear main bearing cap and block 2C•22 2.5 and 3.0 litre engine in-car repair procedures 13.8 Undo the retaining screws and remove the cover from the oil pump 13.9 Note the identification markings (where present) on the pump rotors . . . 13.10 . . . then lift both rotors out of the housing 13.11a Slacken and remove the oil pressure relief valve bolt and sealing washer . . . 13.11b . . . then remove the valve plunger and spring from the pump 13.11c Slacken and remove the safety valve bolt and sealing washer . . . 9 Using a suitable marker pen, mark the surface of both the pump inner and outer rotors; the marks can then be used to ensure the rotors are refitted the correct way around. On some pump identification marks may already exist on the rotors (see illustration). 10 Lift out the inner and outer rotors from the pump housing (see illustration). 11 Unscrew the oil pressure relief valve and the safety valve bolts from the top of the housing and withdraw the valve springs and plungers from the housing, noting which way around the plungers are fitted. Remove the sealing washers from the valve bolts (see illustrations). Note: The pressure relief valve can be removed with pump in position on the engine unit once the timing belt front cover has been removed. 12 Clean the components, and carefully examine the rotors, pump body and valve plungers for any signs of scoring or wear. Renew any component which shows signs of wear or damage; if the rotors or pump housing are marked then the complete pump assembly should be renewed. 13 If the components appear serviceable, measure the rotor endfloat, and check the flatness of the end cover. If the clearances exceed the specified tolerances, the pump must be renewed. 14 If the pump is satisfactory, reassemble the components in the reverse order of removal, noting the following. a) Ensure both rotors are fitted the correct way around. b) Tighten the pump cover screws to the specified torque. c) Fit new sealing rings to the valve bolts and ensure the plungers and springs are fitted the correct way around (see illustrations). 13.11d . . . and withdraw the spring and plunger from the pump Overhaul 8 Undo the retaining screws and lift off the pump cover from the rear of the housing (see illustration). 13.14a Oil pressure relief valve components 1 Spring 2 Plunger 3 Sealing washer 4 Valve bolt 13.14b Safety valve components 1 Plunger 2 Spring 3510 Vauxhall/Opel Omega 3 Sealing washer 4 Valve bolt 2.5 and 3.0 litre engine in-car repair procedures 2C•23 d) On completion prime the oil pump by filling it with clean engine oil whilst rotating the inner rotor. Refitting 15 Prior to refitting it is necessary to determine which of the three possible types of oil pump assembly is fitted to your engine. The first step is to check the diameter of the oil pump retaining bolts; during the 1999 model year the pump retaining bolt diameter was increased from M6 to M8. If M6 retaining bolts are used, it will then be necessary to determine whether the engine is fitted with an original oil pump and timing belt rear cover arrangement or the modified arrangement (see illustration). The modified cover has an additional hole through which the oil pump upper bolt (number 6 in the tightening sequence) can be reached and this affects the refitting procedure. Proceed as described under the relevant sub-heading. Oil pump with M6 retaining bolts and the original timing belt rear cover 16 Prior to refitting, carefully lever out the crankshaft oil seal using a flat-bladed screwdriver. Fit the new oil seal, ensuring its sealing lip is facing inwards, and press it squarely into the housing using a tubular drift which bears only on the hard outer edge of the seal (see illustrations). Press the seal into position so that it is flush with the housing and lubricate the oil seal lip with clean engine oil. 17 Ensure the mating surfaces of the oil pump and cylinder block are clean and dry and the locating dowels are in position. 18 Apply a thin coat of sealant (Vauxhall recommend the use of sealant 15 03 170 available from your Vauxhall dealer), approximately 0.2 mm thick, to the shaded areas of the oil pump side of the new pump gasket as shown (see illustration). 19 Fit the gasket to the cylinder block then carefully manoeuvre the oil pump into position and engage the inner rotor with the crankshaft end. Locate the pump on the dowels, taking great care not damage the oil seal lip (see illustrations). 20 Refit the pump housing retaining bolts in their original locations and tighten them to the initial specified torque in the order shown (see illustration). 13.18 Apply sealant (see text) to the shaded areas of the oil pump side of the new gasket 13.15 Oil pump and timing belt rear cover identification details (pump retained by M6 bolts) A Original pump and timing belt cover B Modified pump and timing belt cover (shaded areas show differences) which allow access to the bolt shown with the cover in position 2C 13.16a Lever out the oil seal out from the pump with a large flat-bladed screwdriver . . . 13.16b . . . and tap the new seal squarely into position, using a socket which bears only on the seal outer edge 13.19a Locate the pump gasket on the dowels . . . 13.19b . . . then refit the oil pump assembly 3510 Vauxhall/Opel Omega 2C•24 2.5 and 3.0 litre engine in-car repair procedures 13.20 Oil pump bolt tightening sequence pump with M6 retaining bolts 21 Fit the timing belt lower guide pulley to the pump and tighten its retaining bolt to the specified torque. 22 Refit the alternator lower mounting bolt and tighten to the specified torque (see Chapter 5A). 23 Wait approximately 10 minutes to allow the sealant on the pump gasket to cure then go around again in the specified sequence and tighten them to the final specified torque setting. 24 Remove the lower guide pulley from the oil pump and refit the timing belt rear cover (see Section 6), tightening its retaining bolts to the specified torque. 25 Reconnect the oil pressure sensor wiring connector and secure the wiring guide in position with the bolt. 26 Refit the sump main casting, oil pump pick-up/strainer and sump pan as described in Section 12. 27 Refit the timing belt sprockets, guide pulleys and tensioner then refit the belt as described in Sections 7 and 8. 28 On completion, fit a new oil filter and fill the engine with clean oil as described in Chapter 1. 13.40 Oil pump bolt tightening sequence pump with M8 retaining bolts position with the retaining bolt. 34 Refit the sump main casting, oil pump pick-up/strainer and sump pan as described in Section 12. 35 Refit the timing belt sprockets, guide pulleys and tensioner then refit the belt as described in Sections 7 and 8. Prior to refitting the timing belt outer cover, go around in the specified sequence (see illustration 13.20) and retighten all the oil pump retaining bolts to the specified torque. 36 On completion, fit a new oil filter and fill the engine with clean oil as described in Chapter 1. Oil pump with M8 retaining bolts 37 Remove all traces of locking compound from the oil pump retaining bolt threads. 38 Carry out the operations described in paragraphs 16 to 19. 39 Apply a drop of locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the thread of each pump retaining bolt then refit the bolts in their original locations, tightening them by hand only. 14 Oil cooler removal and refitting Oil pump with M6 retaining bolts and the modified timing belt rear cover 29 Carry out the operations described in paragraphs 16 to 19. 30 Refit the pump housing retaining bolts in their original locations and tighten them to the specified torque in the order shown (see illustration 13.20). 31 Refit the alternator lower mounting bolt and tighten to the specified torque (see Chapter 5A). 32 Refit the timing belt rear cover (see Section 6) and tighten its retaining bolts to the specified torque. 33 Reconnect the oil pressure sensor wiring connector and secure the wiring guide in 40 Go around in the specified sequence and tighten all the pump retaining bolts to the specified stage 1 torque setting (see illustration). 41 Refit the alternator lower mounting bolt and tighten to the specified torque (see Chapter 5A). 42 Go around again in the specified sequence and tighten all the pump retaining bolts to the specified stage 2 torque setting. 43 Reconnect the oil pressure sensor wiring connector and secure the wiring guide in position with the retaining bolt. 44 Refit the timing belt rear cover (see Section 6) and tighten its retaining bolts to the specified torque. 45 Refit the sump main casting, oil pump pick-up/strainer and sump pan as described in Section 12. 46 Refit the timing belt sprockets, guide pulleys and tensioner then refit the belt as described in Sections 7 and 8. 47 On completion, fit a new oil filter and fill the engine with clean oil as described in Chapter 1. 4 Removal 14.3 Disconnect the wiring connectors (arrowed) from the coolant temperature sender and sensor . . . 3510 Vauxhall/Opel Omega 1 Drain the cooling system as described in Chapter 1. 2 Remove the complete inlet manifold, including the manifold flange, as described in Chapter 4A. 3 Disconnect the wiring connectors from the coolant temperature gauge sender and the engine management system coolant temperature sensor which are screwed into the coolant outlet which links the rear of the cylinder heads (see illustration). 2.5 and 3.0 litre engine in-car repair procedures 2C•25 14.4 . . . then release the retaining clips and disconnect the coolant hoses from the outlet elbow 4 Slacken the retaining clips and disconnect the coolant hoses from the cylinder head outlet (see illustration). 5 Unscrew the retaining bolts and remove the coolant outlet from the cylinder heads. Recover the sealing rings and discard them; new ones must be used on refitting (see illustration). 6 Undo the retaining bolts and remove the upper heatshield from the left-hand cylinder bank exhaust manifold. If necessary, to improve access to the rear bolt remove the 14.5 Unscrew the retaining bolts then remove the coolant outlet elbow from between the cylinder heads and recover the sealing washers (arrowed) exhaust system front pipe as described in Chapter 4A. 7 Position a suitable container beneath the oil filter. Unscrew the filter using an oil filter removal tool if necessary, and drain the oil into the container. If the oil filter is damaged or distorted during removal, it must be renewed. Given the low cost of a new oil filter relative to the cost of repairing the damage which could result if a re-used filter springs a leak, it is probably a good idea to renew the filter in any case. 8 Unscrew the union nuts securing the oil cooler pipes to the cylinder block then unscrew the union bolts securing the pipes to the cooler. Recover the sealing washers from each side of the oil cooler unions and position the pipes clear of the oil cooler (see illustrations). 9 Unscrew the large nuts securing the oil cooler unions to the cover then undo the retaining bolts and remove the cover from the top of the cylinder block (see illustrations). Recover the gasket (where fitted) and discard it; sealant will be needed to replace the gasket on refitting. 10 Lift out the oil cooler and remove it from the engine, keeping it upright to prevent oil spillage (see illustration). Recover the sealing rings from the cooler unions and discard them; new ones must be used on refitting. 11 If the oil cooler shows signs of damage it must be renewed. Refitting 14.8a Slacken the union nuts (arrowed) securing the oil pipes to the block . . . 14.8b . . . then remove the union bolts and sealing washers (arrowed) and free the pipes from the oil cooler 12 Ensure the mating surfaces of the oil cooler, cover and cylinder block are clean and dry. 13 Fit new sealing rings to the oil cooler unions then refit the cover and screw on the large nuts, tightening them by hand only at this stage. 14.9a Unscrew the large nuts from the cooler unions . . . 14.9b . . . then undo the retaining bolts and lift off the oil cooler cover 14.10 Removing the oil cooler from the cylinder block 3510 Vauxhall/Opel Omega 2C 2C•26 2.5 and 3.0 litre engine in-car repair procedures 14.14 Apply a bead of sealant to the groove in the oil cooler cover 14 Apply a bead of suitable sealant (Vauxhall recommend the use of sealant 15 03 296 available from your Vauxhall dealer), approximately 2 mm in diameter, to the groove on the oil cooler cover (see illustration). 15 Refit the cooler assembly to the cylinder block and refit the cover retaining bolts, tightening them evenly and progressively to their specified torque. Once the cover bolts are correctly tightened, tighten the cooler nuts to their specified torque (see illustration). 16 Manoeuvre the oil cooler pipes into position and screw their union nuts into the cylinder block by a few turns each. Position a new sealing washer on each side of the pipe unions then refit the union bolts. Tighten the union bolts to the specified torque then tighten the pipe union nuts to the specified torque. 17 Fit new sealing rings to each side of the coolant outlet then refit it to the cylinder heads, tightening its retaining bolts to the specified torque. Reconnect the hoses to the outlet, securing them in position with the retaining clips, and the temperature sensor wiring connectors. 18 Refit the inlet manifold as described in Chapter 4A and install the exhaust manifold heatshield and (where necessary) front pipe. 14.15 Tighten the cover retaining bolts to the specified torque then tighten the cooler nuts to their specified torque 19 Fit a new oil filter and refill the cooling system as described in Chapter 1. 20 On completion, check the engine oil level as described in Weekly checks. 15 Flywheel/driveplate removal, inspection and refitting 4 Note: New flywheel/driveplate retaining bolts will be required on refitting. Removal Manual transmission models 1 Remove the transmission as described in Chapter 7A then remove the clutch assembly as described in Chapter 6. 2 Prevent the flywheel from turning by locking the ring gear teeth with a similar arrangement to that shown (see illustration). Alternatively, bolt a strap between the flywheel and the cylinder block/crankcase. Make alignment marks between the flywheel and crankshaft using paint or a suitable marker pen. 3 Slacken and remove the retaining bolts and remove the flywheel. Do not drop it, as it is very heavy. Automatic transmission models 4 Remove the transmission as described in Chapter 7B. 5 Lock the driveplate as described in paragraph 2 then slacken the driveplate retaining bolts. 6 Unscrew the retaining bolts and remove the retaining plate, centering ring and driveplate from the end of the crankshaft, noting each components correct fitted location. Inspection 15.2 Lock the flywheel/driveplate ring gear with a tool similar to that shown 7 On manual transmission models, examine the flywheel for scoring of the clutch face. If the clutch face is scored, the flywheel may be surface-ground, but renewal is preferable. 3510 Vauxhall/Opel Omega Check for wear or chipping of the ring gear teeth, if the teeth are damaged the flywheel must be renewed (ring gear renewal is not possible). 8 On automatic transmission models closely examine the driveplate for ring gear teeth for signs of wear or damage and check the driveplate surface for any signs of cracks. 9 If there is any doubt about the condition of the flywheel/driveplate, seek the advice of a Vauxhall dealer or engine reconditioning specialist. They will be able to advise if it is possible to recondition it or whether renewal is necessary. Refitting Manual transmission models 10 Clean the mating surfaces of the flywheel and crankshaft and remove all traces of locking compound from the flywheel retaining bolt threads in the crankshaft. 11 Offer up the flywheel and fit the new retaining bolts. If the original is being refitted align the marks made prior to removal. 12 Lock the flywheel by the method used on removal, and tighten the retaining bolts to the specified stage 1 torque setting then angletighten the bolts through the specified stage 2 angle, using a socket and extension bar, and finally through the specified stage 3 angle. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy. If a gauge is not available, use white paint to make alignment marks between the bolt head and flywheel prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 13 Refit the clutch as described in Chapter 6 then remove the locking tool, and refit the transmission as described in Chapter 7A. Automatic transmission models 14 Clean the mating surfaces of the driveplate and crankshaft and remove all 2.5 and 3.0 litre engine in-car repair procedures 2C•27 traces of locking compound from the driveplate retaining bolt threads in the crankshaft. 15 Offer up the driveplate complete with the centering ring and retaining plate, making sure all components are fitted the correct way around, then screw in the new retaining bolts. 16 Tighten the retaining bolts through the specified torque and angles as described in paragraph 12 then remove the locking tool and refit the transmission as described in Chapter 7B. 16 Crankshaft oil seals renewal 4 Front (timing belt end) oil seal 1 Remove the crankshaft sprocket and spacer as described in Section 8. 2 Carefully punch or drill two small holes opposite each other in the oil seal. Screw a self-tapping screw into each and pull on the screws with pliers to extract the seal. Alternatively carefully lever the seal out of position. Caution: Great care must be taken to avoid damage to the oil pump 3 Clean the seal housing and polish off any burrs or raised edges which may have caused the seal to fail in the first place. 4 Lubricate the lips of the new seal with clean engine oil and ease it into position on the end of the shaft. Press the seal squarely into position until it is flush with the housing. If necessary, a suitable tubular drift, such as a socket, which bears only on the hard outer edge of the seal can be used to tap the seal into position. Take great care not to damage the seal lips during fitting and ensure that the seal lips face inwards. 5 Wash off any traces of oil, then refit the spacer and crankshaft sprocket as described in Section 8. levering against it to check for free play; where this is not possible, enlist the aid of an assistant to move the engine/transmission unit back and forth, or from side to side, while you watch the mounting. While some free play is to be expected even from new components, excessive wear should be obvious. If excessive free play is found, check first that the fasteners are correctly secured, then renew any worn components as described below. 16.7 Fitting a new crankshaft rear oil seal Rear (flywheel/driveplate end) oil seal 6 Remove the flywheel/driveplate as described in Section 15. 7 Renew the seal as described in paragraphs 2 to 4 (see illustration). 8 Refit the flywheel/driveplate as described in Section 15. 17 Engine/transmission mountings inspection and renewal 3 Inspection 1 If improved access is required, raise the front of the car and support it securely on axle stands. Undo the retaining bolts and remove the undercover from beneath the engine unit. 2 Check the mounting rubber to see if it is cracked, hardened or separated from the metal at any point; renew the mounting if any such damage or deterioration is evident. 3 Check that all the mounting’s fasteners are securely tightened; use a torque wrench to check if possible. 4 Using a large screwdriver or a pry bar, check for wear in the mounting by carefully 17.8a Slacken and remove the upper and lower nuts . . . Renewal Left- and right-hand engine mountings Note: It is recommended that the engine mountings are replaced as a matched pair. 5 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. If necessary, to improve access undo the retaining screws and remove the undercover from beneath the engine unit. 6 Support the weight of the engine/transmission using a trolley jack with a block of wood placed on its head. Alternatively attach an engine hoist/support bar to the lifting brackets on the cylinder head and use this to support the engine. 7 Slacken and remove the mounting bolts and remove the vibration damper (where fitted) from the mounting assembly. 8 Unscrew the upper and lower nuts securing the relevant engine mounting to the cylinder block bracket and subframe then raise the engine unit slightly and manoeuvre the mounting out of position (see illustrations). If necessary the mounting bracket can be unbolted and removed from the cylinder block. Note: Take great care not to place any excess stress on any engine wiring/hoses or the exhaust system or when raising the engine. 9 Check all components for signs of wear or damage, and renew as necessary. 17.8b . . . then lift the engine slightly until there is sufficient clearance to manoeuvre the mounting out of position 3510 Vauxhall/Opel Omega 2C 2C•28 2.5 and 3.0 litre engine in-car repair procedures 10 On refitting, refit the mounting to the subframe aligning its locating lug with the subframe slot then refit the lower nut and tighten to the specified torque. 11 Refit the mounting bracket (where removed) to the cylinder block and tighten its retaining bolts to the specified torque. 12 Lower the engine unit back down onto the mounting then refit the upper retaining nut to the mounting, tightening it to the specified torque. 13 Where necessary, refit the vibration damper to the mounting bracket and subframe and tighten its mounting bolts to the specified torque. 14 Refit the undercover (where removed) then lower the vehicle to the ground. Transmission unit rear mounting 15 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 16 Place a jack with a block of wood beneath the transmission, and raise the jack to take the weight of the transmission. 17 With the transmission securely supported, slacken and remove the bolts securing the transmission unit rear mounting crossmember to the vehicle body. Unscrew the nuts securing the crossmember to the mounting and remove it from the vehicle. 18 Slacken and remove the bolts and remove the mounting from the base of the transmission unit. 19 Check all components for signs of wear or 3510 Vauxhall/Opel Omega damage, and renew as necessary. Remove all traces of locking compound from the crossmember to body bolt threads. 20 Fit the mounting to the transmission unit and tighten its retaining bolts to the specified torque. 21 Refit the crossmember to the mounting and lightly tighten its retaining nuts. 22 Apply a few drops of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of each crossmember to body bolt then refit both bolts and tighten them to the specified torque. 23 Remove the jack from underneath the transmission unit then tighten the mounting to crossmember nuts to the specified torque before lowering the vehicle to the ground. 2D•1 Chapter 2 Part D: General engine overhaul procedures Contents Crankshaft - inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Crankshaft - refitting and main bearing running clearance check . . . 17 Crankshaft - removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Cylinder block - cleaning and inspection . . . . . . . . . . . . . . . . . . . . . 11 Cylinder head - dismantling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Cylinder head - reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Cylinder head and valves - cleaning and inspection . . . . . . . . . . . . . 7 Engine - initial start up after overhaul . . . . . . . . . . . . . . . . . . . . . . . . 19 Engine - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Engine overhaul - dismantling sequence . . . . . . . . . . . . . . . . . . . . . . 5 Engine overhaul - general information . . . . . . . . . . . . . . . . . . . . . . . . 2 Engine overhaul - reassembly sequence . . . . . . . . . . . . . . . . . . . . . . 15 Engine removal - methods and precautions . . . . . . . . . . . . . . . . . . . 3 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Main and big-end bearings - inspection . . . . . . . . . . . . . . . . . . . . . . 14 Piston rings - refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Piston/connecting rod assembly - inspection . . . . . . . . . . . . . . . . . . 12 Piston/connecting rod assembly - refitting and big-end running clearance check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Piston/connecting rod assembly - removal . . . . . . . . . . . . . . . . . . . . 9 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic Specifications Cylinder head 2.0 litre engine Maximum gasket face distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder head height: SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve seat width: SOHC engine: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve guide height in cylinder head: SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine Maximum gasket face distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder head height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve seat width: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve guide height in cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 mm 95.75 to 96.25 mm 134 mm 1.0 to 1.5 mm 1.7 to 2.2 mm 1.0 to 1.4 mm 1.4 to 1.8 mm 83.25 to 84.05 mm 13.70 to 14.00 mm 0.05 mm 134 mm 1.0 to 1.4 mm 1.4 to 1.8 mm 13.7 to 14.0 mm 3510 Vauxhall/Opel Omega 4 Very difficult, suitable for expert DIY or professional 5 2D 2D•2 General engine overhaul procedures Valves and guides 2.0 litre engine Valve stem diameter*: SOHC engine: Inlet: Standard (GM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm - GM K1) . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.150 mm - GM K2) . . . . . . . . . . . . . . . . . . . . . . . 3rd oversize (0.250 mm - A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust: Standard (GM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm - GM K1) . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.150 mm - GM K2) . . . . . . . . . . . . . . . . . . . . . . . 3rd oversize (0.250 mm - A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Inlet: Standard (GM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm - GM K1) . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.150 mm - GM K2) . . . . . . . . . . . . . . . . . . . . . . . Exhaust: Standard (GM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm - GM K1) . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.0150 mm - GM K2) . . . . . . . . . . . . . . . . . . . . . . Valve stem runout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve guide bore diameter: SOHC engine: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.150 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3rd oversize (0.250 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.150 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stem-to-guide clearance: SOHC engine: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve length: SOHC engine: Inlet: Standard valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust: Standard valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Inlet: Standard valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust: Standard valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve stem fitted height: SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Standard valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve head diameter: SOHC engine: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.998 to 7.012 mm 7.073 to 7.087 mm 7.148 to 7.162 mm 7.248 to 7.262 mm 6.978 to 6.992 mm 7.053 to 7.067 mm 7.128 to 7.142 mm 7.228 to 7.262 mm 5.955 to 5.970 mm 6.030 to 6.045 mm 6.105 to 6.120 mm 5.945 to 5.960 mm 6.020 to 6.035 mm 6.095 to 6.110 mm Less than 0.03 mm 7.030 to 7.050 mm 7.105 to 7.125 mm 7.180 to 7.200 mm 7.280 to 7.300 mm 6.000 to 6.012 mm 6.075 to 6.090 mm 6.150 to 6.165 mm 0.018 to 0.052 mm 0.038 to 0.072 mm 0.030 to 0.057 mm 0.040 to 0.067 mm 104.0 to 104.4 mm 103.6 to 104.0 mm 103.75 to 104.25 mm 103.35 to 103.85 mm 101.9 to 102.3 mm 101.5 to 101.9 mm 92.05 to 92.45 mm 91.65 to 92.05 mm 17.85 to 18.25 mm 39.6 to 40.2 mm 39.2 to 39.8 mm 41.8 mm 36.5 mm 31.9 to 32.1 mm 28.9 to 29.1 mm 3510 Vauxhall/Opel Omega General engine overhaul procedures 2D•3 Valves and guides (continued) 2.5 and 3.0 litre engine Valve stem diameter*: Inlet: Standard (GM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm - GM K1) . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.150 mm - GM K2) . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust: Standard (GM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm - GM K1) . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.0150 mm - GM K2) . . . . . . . . . . . . . . . . . . . . . . . . Valve stem runout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve guide bore diameter: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st oversize (0.075 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd oversize (0.150 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stem-to-guide clearance: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve length: Inlet: Standard valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust: Standard valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve head diameter: Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . *Identification marking in brackets 5.955 to 5.970 mm 6.030 to 6.045 mm 6.105 to 6.120 mm 5.945 to 5.960 mm 6.020 to 6.035 mm 6.095 to 6.110 mm Less than 0.03 mm 6.000 to 6.012 mm 6.075 to 6.090 mm 6.150 to 6.165 mm 0.030 to 0.057 mm 0.040 to 0.067 mm 101.9 to 102.3 mm 101.5 to 101.9 mm 92.05 to 92.45 mm 91.65 to 92.05 mm 31.9 to 32.1 mm 28.9 to 29.1 mm Cylinder block 2.0 litre engine Maximum gasket face distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder bore diameter: Standard: Size group 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize (0.5 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum cylinder bore ovality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum cylinder bore taper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine Maximum gasket face distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder bore diameter: 2.5 litre engine: Standard: Size group 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize (0.5 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine: Standard: Size group 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize (0.5 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum cylinder bore ovality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum cylinder bore taper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 mm 2D 85.975 to 85.985 mm 85.985 to 85.995 mm 85.995 to 86.005 mm 86.005 to 86.015 mm 86.015 to 86.025 mm 86.465 to 86.475 mm 0.013 mm 0.013 mm 0.05 mm 81.575 to 81.585 mm 81.585 to 81.595 mm 81.595 to 81.605 mm 81.605 to 81.615 mm 81.615 to 81.625 mm 82.065 to 82.075 mm 85.975 to 85.985 mm 85.985 to 85.995 mm 85.995 to 86.005 mm 86.005 to 86.015 mm 86.015 to 86.025 mm 86.465 to 86.475 mm 0.013 mm 0.013 mm 3510 Vauxhall/Opel Omega 2D•4 General engine overhaul procedures Pistons and rings 2.0 litre engine Piston diameter: Standard: Size group 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize (0.5 mm) - size group 7 + 0.5 . . . . . . . . . . . . . . . . . . . . . . . . Piston-to-bore clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Piston ring end gaps (fitted in bore): Top and second compression rings . . . . . . . . . . . . . . . . . . . . . . . . . . Oil control ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Piston ring thickness: Top and second compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil control ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Piston ring-to-groove clearance: Top and second compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil control ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine Piston diameter: 2.5 litre engine: Standard: Size group 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize (0.5 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine: Standard: Size group 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 99 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size group 02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oversize (0.5 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Piston-to-bore clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Piston ring end gaps (fitted in bore): Top and second compression rings . . . . . . . . . . . . . . . . . . . . . . . . . . Oil control ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Piston ring thickness: Top and second compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil control ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Piston ring-to-groove clearance: Top and second compression ring . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil control ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.945 to 85.955 mm 85.955 to 85.965 mm 85.965 to 85.975 mm 85.975 to 85.985 mm 85.985 to 85.995 mm 86.435 to 86.445 mm 0.02 to 0.04 mm 0.3 to 0.5 mm 0.4 to 1.4 mm 1.5 mm 3.0 mm 0.02 to 0.04 mm 0.01 to 0.03 mm 81.540 to 81.550 mm 81.550 to 81.560 mm 81.560 to 81.570 mm 81.570 to 81.580 mm 81.580 to 81.590 mm 82.030 to 82.040 mm 85.940 to 85.950 mm 85.950 to 85.960 mm 85.960 to 85.970 mm 85.970 to 85.980 mm 85.980 to 85.990 mm 86.430 to 86.440 mm 0.025 to 0.045 mm 0.3 to 0.5 mm 0.4 to 1.4 mm 1.5 mm 3.0 mm 0.02 to 0.04 mm 0.01 to 0.03 mm Gudgeon pins 2.0 litre engine Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gudgeon pin-to-piston clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine Diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Length: 2.5 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gudgeon pin-to-piston clearance: 2.5 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gudgeon pin-to-connecting rod clearance: 2.5 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.990 to 21.000 mm 61.2 to 61.8 mm 0.011 to 0.014 mm 20.990 to 21.000 mm 55.7 to 56.0 mm 57.7 to 58.0 mm 0.011 to 0.014 mm 0.001 to 0.015 mm Interference-fit 0.014 to 0.030 mm 3510 Vauxhall/Opel Omega General engine overhaul procedures 2D•5 Crankshaft 2.0 litre engine Endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main bearing journal diameter: Standard: 1st size group (white) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd size group (green) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3rd size group (brown) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st (0.25 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd (0.50 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Big-end bearing journal (crankpin) diameter: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st (0.25 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd (0.50 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Journal out-of round . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Journal taper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft runout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main bearing running clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Big-end bearing (crankpin) running clearance . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine Endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main bearing journal diameter: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st (0.25 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd (0.50 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Big-end bearing journal (crankpin) diameter: 2.5 litre engine: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st (0.25 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd (0.50 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1st (0.25 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2nd (0.50 mm) undersize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Journal out-of round . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Journal taper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft runout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Main bearing running clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Big-end bearing (crankpin) running clearance . . . . . . . . . . . . . . . . . . . . 0.05 to 0.15 mm 57.974 to 57.981 mm 57.981 to 57.988 mm 57.988 to 57.995 mm 57.732 to 57.745 mm 57.482 to 57.495 mm 48.970 to 48.988 mm 48.720 to 48.738 mm 48.470 to 48.488 mm 0.04 mm 0.04 mm Less than 0.03 mm 0.015 to 0.043 mm 0.006 to 0.031 mm 0.01 to 0.76 mm 67.980 to 67.996 mm 67.730 to 67.746 mm 67.480 to 67.496 mm 48.971 to 48.990 mm 48.721 to 48.740 mm 48.471 to 48.490 mm 53.971 to 53.990 mm 53.721 to 53.740 mm 53.471 to 53.490 mm 0.04 mm 0.04 mm Less than 0.03 mm 0.014 to 0.043 mm 0.010 to 0.061 mm 2D Torque wrench settings 2.0 litre engine SOHC engine - Refer to Chapter 2A Specifications DOHC engine - Refer to Chapter 2B Specifications 2.5 and 3.0 litre engine Refer to Chapter 2C Specifications 1 General information 1 Included in this Part of Chapter 2 are details of removing the engine from the vehicle and general overhaul procedures for the cylinder head, cylinder block and all other engine internal components. 2 The information given ranges from advice concerning preparation for an overhaul and the purchase of replacement parts, to detailed step-by-step procedures covering removal, inspection, renovation and refitting of engine internal components. 3 After Section 5, all instructions are based on the assumption that the engine has been removed from the car. For information concerning in-car engine repair, as well as the removal and refitting of those external components necessary for full overhaul, refer to the relevant in-car repair procedure section (Chapter 2A to 2C) of this Chapter and to Section 7. Ignore any preliminary dismantling operations described in the relevant in-car repair sections that are no longer relevant once the engine has been removed from the car. 4 Apart from torque wrench settings, which are given at the beginning of the relevant incar repair procedure Chapter (2A to 2C), all specifications relating to engine overhaul are at the beginning of this Part of Chapter 2. 3510 Vauxhall/Opel Omega 2 Engine overhaul general information 1 It is not always easy to determine when, or if, an engine should be completely overhauled, as a number of factors must be considered. 2 High mileage is not necessarily an indication that an overhaul is needed, while low mileage does not preclude the need for an overhaul. Frequency of servicing is probably the most important consideration. An engine which has had regular and frequent oil and filter changes, as well as other required maintenance, should give many thousands of 2D•6 General engine overhaul procedures miles of reliable service. Conversely, a neglected engine may require an overhaul very early in its life. 3 Excessive oil consumption is an indication that piston rings, valve seals and/or valve guides are in need of attention. Make sure that oil leaks are not responsible before deciding that the rings and/or guides are worn. Perform a compression test, as described in Part A of this Chapter, to determine the likely cause of the problem. 4 Check the oil pressure with a gauge fitted in place of the oil pressure switch, and compare it with that specified. If it is extremely low, the main and big-end bearings, and/or the oil pump, are probably worn out. 5 Loss of power, rough running, knocking or metallic engine noises, excessive valve gear noise, and high fuel consumption may also point to the need for an overhaul, especially if they are all present at the same time. If a complete service does not remedy the situation, major mechanical work is the only solution. 6 An engine overhaul involves restoring all internal parts to the specification of a new engine. During an overhaul, the pistons and the piston rings are renewed. New main and big-end bearings are generally fitted; if necessary, the crankshaft may be reground/renewed, to restore the journals. The valves are also serviced as well, since they are usually in less-than-perfect condition at this point. While the engine is being overhauled, other components, such as the starter and alternator, can be overhauled as well. The end result should be an as-new engine that will give many troublefree miles. Note: Critical cooling system components such as the hoses, thermostat and coolant pump should be renewed when an engine is overhauled. The radiator should be checked carefully, to ensure that it is not clogged or leaking. Also, it is a good idea to renew the oil pump whenever the engine is overhauled. 7 Before beginning the engine overhaul, read through the entire procedure, to familiarise yourself with the scope and requirements of the job. Overhauling an engine is not difficult if you follow carefully all of the instructions, have the necessary tools and equipment, and pay close attention to all specifications. It can, however, be time-consuming. Plan on the car being off the road for a minimum of two weeks, especially if parts must be taken to an engineering works for repair or reconditioning. Check on the availability of parts and make sure that any necessary special tools and equipment are obtained in advance. Most work can be done with typical hand tools, although a number of precision measuring tools are required for inspecting parts to determine if they must be renewed. Often the engineering works will handle the inspection of parts and offer advice concerning reconditioning and renewal. Note: Always wait until the engine has been completely dismantled, and until all components (especially the cylinder block and the crankshaft) have been inspected, before deciding what service and repair operations must be performed by an engineering works. The condition of these components will be the major factor to consider when determining whether to overhaul the original engine, or to buy a reconditioned unit. Do not, therefore, purchase parts or have overhaul work done on other components until they have been thoroughly inspected. As a general rule, time is the primary cost of an overhaul, so it does not pay to fit worn or sub-standard parts. 8 As a final note, to ensure maximum life and minimum trouble from a reconditioned engine, everything must be assembled with care, in a spotlessly-clean environment. 3 Engine removal methods and precautions 1 If you have decided that the engine must be removed for overhaul or major repair work, several preliminary steps should be taken. 2 Locating a suitable place to work is extremely important. Adequate work space, along with storage space for the car, will be needed. If a workshop or garage is not available, at the very least, a flat, level, clean work surface is required. 3 Cleaning the engine compartment and engine/transmission before beginning the removal procedure will help keep tools clean and organised. 4 An engine hoist or A-frame will also be necessary. Make sure the equipment is rated in excess of the weight of the engine. Safety is of primary importance, considering the potential hazards involved in lifting the engine out of the car. 5 If this is the first time you have removed an engine, an assistant should ideally be available. Advice and aid from someone more experienced would also be helpful. There are many instances when one person cannot simultaneously perform all of the operations required when lifting the engine out of the vehicle. 6 Plan the operation ahead of time. Before starting work, arrange for the hire of or obtain all of the tools and equipment you will need. Some of the equipment necessary to perform engine removal and installation safely and with relative ease (in addition to an engine hoist) is as follows: a heavy duty trolley jack, complete sets of spanners and sockets as described in the front of this manual, wooden blocks, and plenty of rags and cleaning solvent for mopping up spilled oil, coolant and fuel. If the hoist must be hired, make sure that you arrange for it in advance, and perform all of the operations possible without it beforehand. This will save you money and time. 3510 Vauxhall/Opel Omega 7 Plan for the car to be out of use for quite a while. An engineering works will be required to perform some of the work which the do-ityourselfer cannot accomplish without special equipment. These places often have a busy schedule, so it would be a good idea to consult them before removing the engine, in order to accurately estimate the amount of time required to rebuild or repair components that may need work. 8 Always be extremely careful when removing and refitting the engine. Serious injury can result from careless actions. Plan ahead and take your time, and a job of this nature, although major, can be accomplished successfully. 4 Engine removal and refitting 4 Note: On 2.5 and 3.0 litre engine models with air conditioning, it will be necessary to disconnect the refrigerant lines in order to remove the engine unit from the vehicle (see Warnings in Chapter 3). Have the refrigerant discharged by an air conditioning specialist before starting work and have ready some caps/plugs to plug the hose/pipe end fittings whilst the engine is removed. On completion it will be necessary to have the system recharged by an air conditioning specialist. Do not operate the air conditioning system whilst it is discharged. Removal 1 Park the vehicle on firm, level ground then remove the bonnet as described in Chapter 11. 2 Remove the battery as described in Chapter 5A. 3 Chock the rear wheels, then firmly apply the handbrake. Apply the handbrake, then jack up the front of the vehicle. Securely support it on axle stands then undo the retaining screws and remove the undercover from beneath the engine unit. 4 Drain the cooling system as described in Chapter 1. If the engine is to be dismantled, also drain the engine oil and remove the oil filter. 5 Working as described in Chapter 4A, depressurise the fuel system then remove the engine management electronic control unit (ECU). 6 Remove the lid from the engine compartment relay box and trace the engine wiring harness into the box. Unclip the injection system relay connectors from the box then disconnect the harness connector(s) (see illustrations). Free the sealing grommet and position the harness clear of the relay box. 7 Disconnect the engine wiring harness connectors which are located at the rear of the battery (see illustration). General engine overhaul procedures 2D•7 4.6a Unclip the injection system relays . . . 4.6b . . . and disconnect the engine wiring harness connector from the relay box 8 Free the engine wiring harness auxiliary connections connector from the battery positive terminal so the harness is free to be removed with the engine and (where necessary) unbolt the earth lead from the front of the engine. On some models the harness is connected to the fusible link housing instead of the battery terminal; where this is the case, remove the fusible link and unclip the connector from the housing (see illustrations). Proceed as described under the relevant sub-heading. disconnect the radiator top hose from the cylinder head. 12 Remove the cooling fan from the rear of the radiator as described in Chapter 3. 13 Referring to Chapter 10, unbolt the power steering pump and position it clear of the engine unit with its hoses still attached. 14 On models with air conditioning, unbolt the compressor and position it clear of the engine with its pipes/hoses still attached. Do not open the refrigerant system (see Chapter 3). 15 Attach the hoist to the engine lifting brackets then remove the transmission unit as described in Chapter 7A or 7B, as applicable. 16 Make a final check that any components which would prevent the removal of the engine from the car have been removed or disconnected. Ensure all wiring/hoses are secured so that they cannot be damaged on removal. 17 Slacken and remove the nuts securing the left- and right-hand engine mounting brackets to the top of the mountings 18 With the aid of assistant, lift the engine until the brackets are clear of the mountings then carefully move the engine forwards sufficiently to allow it to be lifted cleanly out of position and clear of the vehicle. Great care must be taken to ensure that no components are trapped and damaged during the removal procedure. 19 Lower the engine onto a suitable work area and detach the hoist. 2.0 litre SOHC engine 9 Referring to Chapter 4A, carry out the following procedures. a) Remove the air cleaner housing and intake ducts. b) Remove the exhaust front pipe. c) Disconnect the fuel feed and return hoses from the fuel rail. d) Disconnect the accelerator cable and (where necessary) cruise control cable from the throttle linkage then unbolt the cable mounting bracket and position it clear of the engine. e) Disconnect the brake servo hose and various vacuum hoses and from the inlet manifold, noting each hoses correct fitted location. Also disconnect the coolant hose from the throttle housing. 10 Remove the DIS module as described in Chapter 5B. Once the module has been removed, refit the lifting bracket to the cylinder head and securely tighten the retaining bolt. 11 Disconnect the engine coolant hose from the rear of the coolant pipe on the right-hand side of the engine compartment. Also 4.8a Where necessary, remove the fusible link . . . 4.7 Disconnect the engine wiring harness connectors which are located at the rear of the battery a) Remove the air cleaner housing and intake ducts. b) Remove the throttle housing. c) Remove the exhaust front pipe. d) Disconnect the fuel feed and return hoses from the fuel rail. e) Disconnect the brake servo hose and various vacuum hoses and from the inlet manifold, noting each hoses correct fitted location. Also disconnect the hose from the secondary air injection valve on the exhaust manifold. 21 Disconnect the engine coolant hose from the rear of the coolant pipe on the right-hand side of the engine compartment. Also disconnect the radiator top hose from the cylinder head and the hose from the DIS module mounting bracket on the rear of the cylinder head. 22 Remove the engine as described in paragraphs 12 to 19. 2.5 and 3.0 litre engine 20 Referring to Chapter 4A, carry out the following procedures. 23 Remove the windscreen wiper motor as described in Chapter 12. 24 Remove the radiator as described in Chapter 3. 25 Slacken the retaining clip and disconnect the radiator top hose from the coolant pipe on the left-hand cylinder head. 26 Wipe clean the area around the hose/pipe unions on the power steering pump (see illustration). Slacken the retaining clip then disconnect the fluid supply hose from the pump and drain the reservoir contents into a suitable container. Unscrew the union nut and 4.8b . . . and unclip the engine harness connector from the fusible link housing 4.26 On 2.5 and 3.0 litre engines, disconnect the fluid supply hose (A) and the feed pipe (B) from the power steering pump 2.0 litre DOHC engine 3510 Vauxhall/Opel Omega 2D 2D•8 General engine overhaul procedures 4.27a Slacken the union nuts and disconnect the fuel hoses from the fuel rail 4.27b Disconnecting the hose from the secondary air injection non-return valve 4.27c Disconnect the multi-ram intake system vacuum hoses from the servo unit pipe disconnect the feed pipe from the pump then plug the hose and pump unions to minimise fluid loss and prevent the entry of dirt into the system. 27 Referring to Chapter 4A, carry out the following procedures. a) Remove the air cleaner housing and intake ducts. b) Disconnect the accelerator cable and (where necessary) cruise control cable from the throttle linkage and free them from the mounting bracket. c) Remove the exhaust front pipes. d) Disconnect the fuel feed and return hoses from the fuel rail (see illustration). e) Disconnect the brake servo hose from the inlet manifold then disconnect the breather hoses from the rear of the manifold and position the servo hose clear of the engine. f) Disconnect the air hose from the secondary air injection non-return valve at the front of the engine (see illustration). g) Disconnect the carbon canister hose from the purge valve and multi-ram intake system vacuum hoses from the servo unit vacuum pipe (see illustration). 28 Release the retaining clips and disconnect the engine coolant hoses from the expansion tank. Remove the retaining clip and slide the tank out of the engine compartment, disconnecting the wiring connector from the level sender as it becomes accessible (see illustrations). 29 Locate the heater matrix coolant hose unions on the bulkhead. Pull back on the quick-release fitting collars and detach both hoses from their unions. Disconnect the vacuum hose from the heater cut-off valve (see illustrations). 30 On models with air conditioning, disconnect the wiring connector from the compressor. Referring to Chapter 3, having had the refrigerant discharged by a specialist, disconnect the compressor refrigerant pipes at their unions on the receiver/drier damper and directly above the left-hand cylinder head. On models with quick-release fittings, separate the unions by sliding back the dust seal and releasing the locking collar tabs by inserting a collar (special tools KM-917-1 and KM-917-2 are designed for this task) into the fitting and on models with screw-type fittings, unscrew the union nuts then disconnect the pipes and recover the union sealing rings. Immediately fit the closure cap/plugs to the pipe/union ends to keep moisture out of the system. Unscrew the mounting clamp bolts and position the damper clear of the engine unit (see illustrations). 4.28a Disconnect the engine coolant hoses from the expansion tank . . . 4.28b . . . and remove the tank retaining clip 4.28c Free the expansion tank from its mountings and remove it, disconnecting the wiring connector from the level sender 4.29a Pull back on the locking collars and detach the heater matrix coolant hoses from their unions on the bulkhead . . . 4.29b . . . then disconnect the vacuum hose from the heater cut-off valve 3510 Vauxhall/Opel Omega 4.30a On models with air conditioning disconnect the wiring connector from the compressor . . . General engine overhaul procedures 2D•9 4.30b . . . and separate the air refrigerant pipes at the unions above the left-hand cylinder head . . . 4.30c . . . and at the front of the engine (quick-release fitting pipes shown) 31 Attach the hoist to the engine lifting brackets then remove the transmission unit as described in Chapter 7A or 7B, as applicable (see illustration). 32 Make a final check that any components which would prevent the removal of the engine from the car have been removed or disconnected. Ensure all wiring/hoses are secured so that they cannot be damaged on removal. 33 Unscrew the mounting bolts and remove the vibration dampers (where fitted) from the left- and right-hand engine mountings. 34 Slacken and remove the nuts securing the left- and right-hand engine mountings to the subframe and engine brackets. 35 With the aid of assistant, lift the engine until the brackets are clear of the mountings then remove both mountings from the vehicle. Carefully move the engine forwards sufficiently to allow it to be lifted cleanly out of position and clear of the vehicle (see illustration). Great care must be taken to ensure that no components are trapped and damaged during the removal procedure. 36 Lower the engine onto a suitable work area and detach the hoist. the engine onto its mounting rubbers. Ensure the brackets are correctly engaged with the mountings then refit the mounting nuts and tighten to the specified torque setting. 39 The remainder of the refitting procedure is a direct reversal of removal, noting the following. Refitting 37 Reconnect the hoist to the engine lifting brackets and, with the aid of an assistant, carefully lift the assembly into position the engine compartment taking great care not to trap any components. 38 Align the engine mounting brackets with the left- and right-hand mountings and lower 4.31 Remove the covers from the engine lifting brackets and attach the hoist a) Refit the transmission unit as described in Chapter 7A or 7B, as applicable. b) On 2.5 and 3.0 litre models with air conditioning, fit new sealing rings to the compressor pipe unions and securely tighten the union nuts (screw-type fittings) or ensure the pipes are pushed securely together until an audible click is emitted (quick-release fittings). On completion have the refrigerant system recharged by an air conditioning specialist before using the vehicle. c) Ensure that all wiring is correctly routed and retained by all the relevant retaining clips and that all connectors are correctly and securely reconnected. d) Ensure that all disturbed hoses are correctly reconnected, and securely retained by their retaining clips. Ensure all the cooling system quick-release fittings are securely retained by their collars. e) Adjust the accelerator cable as described in the Chapter 4A. f) Fit a new oil filter (where necessary) and refill the engine with fresh oil as described in Chapter 1. g) Refill the cooling system as described in Chapter 1. 4.35 Lifting the engine unit out of position 3510 Vauxhall/Opel Omega 4.30d Release the receiver/drier damper mounting bracket and position the damper clear of the engine 5 Engine overhaul dismantling sequence 1 It is much easier to dismantle and work on the engine if it is mounted on a portable engine stand. These stands can often be hired from a tool hire shop. Before the engine is mounted on a stand, the flywheel/driveplate should be removed, so that the stand bolts can be tightened into the end of the cylinder block. 2 If a stand is not available, it is possible to dismantle the engine with it blocked up on a sturdy workbench, or on the floor. Be extracareful not to tip or drop the engine when working without a stand. 3 If you are going to obtain a reconditioned engine, all the external components must be removed first, to be transferred to the replacement engine (just as they will if you are doing a complete engine overhaul yourself). These components include the following: a) Inlet and exhaust manifolds (Chapter 4A). b) Alternator/power steering pump/air conditioning compressor bracket(s) (as applicable). c) Coolant pump (Chapter 3). d) Fuel system components (Chapter 4A). e) Wiring harness and all electrical switches and sensors. f) Oil filter (Chapter 1). g) Flywheel/driveplate (relevant part of this Chapter). Note: When removing the external components from the engine, pay close attention to details that may be helpful or important during refitting. Note the fitted position of gaskets, seals, spacers, pins, washers, bolts, and other small items. 4 If you are obtaining a ‘short’ engine (which consists of the engine cylinder block, crankshaft, pistons and connecting rods all assembled), then the cylinder head(s), sump, oil pump, and timing belt will have to be removed also. 5 If you are planning a complete overhaul, the engine can be dismantled, and the internal components removed, in the order given below, referring to the relevant part of this Chapter unless otherwise stated. 2D 2D•10 General engine overhaul procedures 6.4a Using a valve spring compressor 6.4b Pull off the valve stem seals using a pair of pliers 6.6 Removing a valve a) Inlet and exhaust manifolds (Chapter 4A). b) Timing belt, sprockets and tensioner. c) Cylinder head(s). d) Flywheel/driveplate. e) Sump. f) Oil pump. g) Piston/connecting rod assemblies. h) Crankshaft. 6 Before beginning the dismantling and overhaul procedures, make sure that you have all of the correct tools necessary. Refer to the Tools and working facilities Section of this manual for further information. 1 On 2.0 litre SOHC engines, referring to Part A of this Chapter, remove the cylinder head from the engine then lift the camshaft followers, thrust pads and hydraulic tappets out from the cylinder head. 2 On 2.0 litre DOHC engines remove the camshafts and followers as described in Part B of this Chapter then remove the cylinder head from the engine. 3 On 2.5 and 3.0 litre engines remove the camshafts and followers as described in Part C of this Chapter then remove the cylinder head(s) from the engine. 4 On all models, using a valve spring compressor, compress each valve spring in turn until the split collets can be removed. Release the compressor, and lift off the spring retainer and spring. Using a pair of pliers, carefully extract the valve stem seal from the top of the guide then slide off the spring seat (see illustrations). 5 If, when the valve spring compressor is screwed down, the spring retainer refuses to free and expose the split collets, gently tap the top of the tool, directly over the retainer, with a light hammer. This will free the retainer. 6 Withdraw the valve through the combustion chamber (see illustration). It is essential that each valve is stored together with its collets, retainer, spring, and spring seat. The valves should also be kept in their correct sequence, unless they are so badly worn that they are to be renewed (see Haynes hint). combustion chambers and ports, then wash the cylinder head thoroughly with paraffin or a suitable solvent. Scrape off any heavy carbon deposits that may have formed on the valves, then use a power-operated wire brush to remove deposits from the valve heads and stems. 4 Ensure the cylinder head oilways are clean and free of obstructions. If you have access to compressed air, use it to blow out the oilways and galleries. To ensure a thorough job is done, remove all oil gallery plugs prior to cleaning. Once the galleries are clean, apply suitable sealant to the oil gallery plugs and refit them to the cylinder head, tightening them securely. 6 Cylinder head dismantling 4 Note: New and reconditioned cylinder heads are available from the manufacturer, and from engine overhaul specialists. Be aware that some specialist tools are required for the dismantling and inspection procedures, and new components may not be readily available. It may therefore be more practical and economical for the home mechanic to purchase a reconditioned head, rather than dismantle, inspect and recondition the original head. 7 Cylinder head and valves cleaning and inspection If the components are to be refitted, place each valve and its associated components in a labelled polythene bag or similar small container. Mark the bag/container with the relevant valve number to ensure that it is refitted in its original location 4 Warning: Wear eye protection when using compressed air! Inspection Note: Be sure to perform all the following inspection procedures before concluding that the services of a machine shop or engine overhaul specialist are required. Make a list of all items that require attention. Cylinder head 5 Inspect the head very carefully for cracks, evidence of coolant leakage, and other damage. If cracks are found, a new cylinder head should be obtained. 6 Use a straight-edge and feeler blade to check that the cylinder head surface is not distorted (see illustration). If it is, it may be possible to resurface it, provided that the cylinder head is not reduced to less than the minimum specified height. 1 Thorough cleaning of the cylinder head and valve components, followed by a detailed inspection, will enable you to decide how much valve service work must be carried out during the engine overhaul. Note: If the engine has been severely overheated, it is best to assume that the cylinder head is warped check carefully for signs of this. Cleaning 2 Scrape away all traces of old gasket material from the cylinder head. 3 Scrape away the carbon from the 3510 Vauxhall/Opel Omega 7.6 Checking the cylinder head surface for distortion General engine overhaul procedures 2D•11 7 Examine the valve seats in each of the combustion chambers. If they are severely pitted, cracked or burned, then they will need to be renewed (if possible) or recut by an engine overhaul specialist. If they are only slightly pitted, this can be removed by grinding-in the valve heads and seats with fine valve-grinding compound, as described below. 8 If the valve guides are worn (indicated by a side-to-side motion of the valve, and accompanied by excessive blue smoke in the exhaust when running) new guides must be fitted. Measure the diameter of the existing valve stems (see below) and the bore of the guides, then calculate the clearance and compare the result with the specified value. If the clearance is not within the specified limits, renew the valves and/or guides as necessary. 9 The renewal of valve guides is best carried out by an engine overhaul specialist. If the work is to be carried out at home, however, use a stepped, double-diameter drift to drive out the worn guide towards the combustion chamber. On fitting the new guide, place it first in a deep-freeze for one hour, then drive it into its cylinder head bore from the camshaft side until it projects the specified amount above the cylinder head surface. 10 If the valve seats are to be re-cut this must be done only after the guides have been renewed. Valves Caution: On 3.0 litre engines, the exhaust valves are filled with sodium and must therefore be disposed of carefully. Wearing protective goggles, gloves and some overalls, cut the exhaust valves in half then immerse them in water noting that the sodium will react violently as soon as it contacts the water. When the reaction between the sodium and water has finished, the valves can then be disposed of normally. Dispose of the water bearing in mind that it will contain sodium hydroxide (caustic soda) which is highly corrosive. 11 Examine the head of each valve for pitting, burning, cracks and general wear, and check the valve stem for scoring and wear ridges. Rotate the valve, and check for any obvious indication that it is bent. Look for pitting and excessive wear on the tip of each valve stem. Renew any valve that shows any such signs of wear or damage. 12 If the valve appears satisfactory at this stage, measure the valve stem diameter at several points using a micrometer (see illustration). Any significant difference in the readings obtained indicates wear of the valve stem. Should any of these conditions be apparent, the valve(s) must be renewed. 13 If the valves are in satisfactory condition, they should be ground (lapped) into their respective seats, to ensure a smooth gastight seal. If the seat is only lightly pitted, or if it has been re-cut, fine grinding compound only should be used to produce the required 7.12 Using a micrometer to measure valve stem diameter finish. Coarse valve-grinding compound should not be used unless a seat is badly burned or deeply pitted; if this is the case, the cylinder head and valves should be inspected by an expert to decide whether seat recutting, or even the renewal of the valve or seat insert, is required. 14 Valve grinding is carried out as follows. Place the cylinder head upside-down on a bench. 15 Smear a trace of the appropriate grade of valve-grinding compound on the seat face, and press a suction grinding tool onto the valve head. With a semi-rotary action, grind the valve head to its seat, lifting the valve occasionally to redistribute the grinding compound (see illustration). A light spring placed under the valve head will greatly ease this operation. 16 If coarse grinding compound is being used, work only until a dull, matt even surface is produced on both the valve seat and the valve, then wipe off the used compound and repeat the process with fine compound. When a smooth unbroken ring of light grey matt finish is produced on both the valve and seat, the grinding operation is complete. Do not grind in the valves any further than absolutely necessary, or the seat will be prematurely sunk into the cylinder head. 17 When all the valves have been ground-in, carefully wash off all traces of grinding compound using paraffin or a suitable solvent before reassembly of the cylinder head. 8.1 Lubricate the valve stem with engine oil and insert it into the correct guide 3510 Vauxhall/Opel Omega 7.15 Grinding in a valve Valve components 18 Examine the valve springs for signs of damage and discoloration; if possible; also compare the existing spring free length with new components. 19 Stand each spring on a flat surface, and check it for squareness. If any of the springs are damaged, distorted or have lost their tension, obtain a complete new set of springs. 8 Cylinder head reassembly 4 1 Lubricate the stems of the valves, and insert them into their original locations (see illustration). If new valves are being fitted, insert them into the locations to which they have been ground. 2 Working on the first valve, refit the spring seat. Dip the new valve stem seal in fresh engine oil, then carefully locate it over the valve and onto the guide. Take care not to damage the seal as it is passed over the valve stem. Use a suitable socket or metal tube to press the seal firmly onto the guide (see illustrations). Note: If genuine seals are being fitted there maybe an oil seal protector supplied with the seals; the protector fits over the valve stem and prevents the oil seal lip being damaged on the valve. 3 Locate the spring on the seat and fit the spring retainer (see illustration). 8.2a Fit the spring seat . . . 2D 2D•12 General engine overhaul procedures 8.2b . . . then fit the seal protector (where provided) . . . 8.2c . . . and install the valve stem oil seal 8.3 Fit the valve spring and spring retainer 8.4 Compress the valve and locate the collets in the recess on the valve stem 4 Compress the valve spring, and locate the split collets in the recess in the valve stem (see illustration). Release the compressor, then repeat the procedure on the remaining valves. 8 On 2.5 and 3.0 litre engines, working as described in Part C, refit the cylinder head to the engine and install the followers and camshafts. Use a little dab of grease to hold the collets in position on the valve stem while the spring compressor is released 5 With all the valves installed, using a hammer and interposed block of wood, tap the end of each valve stem to settle the components. 6 On 2.0 litre SOHC engine, working as described in Part A, Sections 11 and 12, refit the hydraulic tappets, thrust pads and followers to the head then refit the cylinder head. 7 On 2.0 litre DOHC engine, working as described in Part B, refit the cylinder head to the engine and install the followers and camshafts. 9 Piston/connecting rod assembly removal 4 Note: New connecting rod big-end cap bolts will be needed on refitting 1 On 2.0 litre SOHC engines, working as described in Part A of this Chapter, remove the cylinder head and sump then unbolt the pick-up/strainer and remove the baffle plate. 2 On 2.0 litre DOHC engines, referring to Part B of this Chapter, remove the cylinder head, sump and oil pick-up/strainer. On later (1998 model year onwards) engines, remove the crankshaft balancer unit. On early (pre 1998 model year) engines with a two-piece sump, 9.3 Removing the baffle plate 2.5 and 3.0 litre engine 3510 Vauxhall/Opel Omega 8.2d Press the oil seal fully onto the guide with a suitable socket unscrew the retaining bolts and remove the baffle plate from the base of the cylinder block; discard the retaining bolts new ones should be used on refitting. 3 On 2.5 and 3.0 litre engines remove the cylinder heads and sump as described in Part C of this Chapter. Unbolt the baffle plate and remove it from the base of the main bearing bridge casting (see illustration). 4 On all models, if there is a pronounced wear ridge at the top of any bore, it may be necessary to remove it with a scraper or ridge reamer, to avoid piston damage during removal. Such a ridge indicates excessive wear of the cylinder bore. 5 Using a hammer and centre-punch, paint or similar, mark each connecting rod and its bearing cap with its respective cylinder number on the flat machined surface provided; if the engine has been dismantled before, note carefully any identifying marks made previously (see illustration). On 2.0 litre engines No 1 cylinder is at the timing belt end of the engine and on 2.5 and 3.0 litre engines No1 cylinder it is at the timing belt end of the right-hand cylinder bank. 6 Turn the crankshaft to bring piston 1 to BDC (bottom dead centre). 7 Unscrew the bolts from No 1 piston big-end bearing cap. Take off the cap and recover the bottom half bearing shell. If the bearing shells are to be re-used, tape the cap and the shell together. 9.5 Make identification markings on the connecting rods and bearing caps (circled). Note that the lug on the bearing cap faces towards the flywheel/driveplate end of the engine General engine overhaul procedures 2D•13 Caution: On some engines, the connecting rod/bearing cap mating surfaces are not machined flat; the big-end bearing caps are ‘cracked’ off from the rod during production and left untouched to ensure the cap and rod mate perfectly. Where this type of connecting rod is fitted, great care must be taken to ensure the mating surfaces of the cap and rod are not marked or damaged in anyway. Any damage to the mating surfaces will adversely affect the strength of the connecting rod and could lead to premature failure. 8 Using a hammer handle, push the piston up through the bore, and remove it from the top of the cylinder block. Recover the bearing shell, and tape it to the connecting rod for safe-keeping. 9 Loosely refit the big-end cap to the connecting rod, and secure with the bolts this will help to keep the components in their correct order. 10 On 2.0 litre engines, remove No 4 piston assembly in the same way then turn the crankshaft through 180° to bring pistons 2 and 3 to BDC (bottom dead centre), and remove them in the same way. 11 On 2.5 and 3.0 litre engines, remove the remaining five piston assemblies in the same way, positioning the crankshaft as necessary to gain access to the bearing cap bolts. 10 Crankshaft removal 4 10.5 The main bearing caps should be numbered (No 1 cap shown) 10.7 Removing the centre (No 3) main bearing cap. Note the thrust flanges incorporated into the bearing shell or a suitable marker pen, number the caps from 1 to 5 from the timing belt end of the engine and mark each cap to indicate its correct fitted direction to avoid confusion on refitting. 6 Working in a diagonal sequence, evenly and progressively slacken the ten main bearing cap retaining bolts by half a turn at a time until all bolts are loose. Remove all bolts. 7 Carefully remove each cap from the cylinder block, ensuring that the lower main bearing shell remains in position in the cap (see illustration). 8 Carefully lift out the crankshaft, taking care not to displace the upper main bearing shells (see illustration). Remove the flywheel/ driveplate end oil seal and discard it. 9 Recover the upper bearing shells from the cylinder block, and tape them to their respective caps for safe-keeping (see illustration). 12 Check the crankshaft endfloat as described in Section 13, then proceed as follows. 13 Prior to removal, check the main bearing bridge casting fitting mark is clearly visible. There should be an arrow on the casting which points towards the timing belt end of the engine. 14 With the cylinder block upside down, slacken and remove the four bolts securing the main bearing bridge casting to the cylinder block. 15 Working in a diagonal sequence, evenly and progressively slacken the eight main bearing cap/bridge retaining bolts by half a turn at a time until all bolts are loose. Remove the bolts then lift off the bridge casting from the cylinder block. 16 The main bearing caps should be numbered 1 to 3 from the timing belt end of the engine; the flywheel/driveplate end bearing cap is not numbered but is easily identified anyway. If the bearing caps are not marked, using a hammer and punch or a suitable marker pen, number the caps from 1 to 3 from the timing belt end of the engine and mark each cap to indicate its correct fitted direction to avoid confusion on refitting. 17 Carefully remove each cap from the cylinder block, ensuring that the lower main bearing shell remains in position in the cap. If the rear cap is a tight-fit, screw two M8 bolts into the threaded holes and use the bolts to pull the cap out (see illustration). 18 Carefully lift out the crankshaft, taking care not to displace the upper main bearing 2.0 litre engine 2.5 and 3.0 litre engines Note: New main bearing cap bolts will be required on refitting. 1 Remove the oil pump and flywheel/driveplate. Refer to Part A for information on SOHC engine and Part B for information on the DOHC engine. 2 Remove the piston and connecting rod assemblies as described in Section 9. If no work is to be done on the pistons and connecting rods, unbolt the caps and push the pistons far enough up the bores that the connecting rods are positioned clear of the crankshaft journals. 3 On earlier DOHC engines with a two-piece sump, evenly and progressively slacken the remaining bolts and remove the main bearing ladder casting from the base of the block. Discard the retaining bolts; new ones must be used on refitting. 4 Check the crankshaft endfloat as described in Section 13, then proceed as follows. 5 The main bearing caps should be numbered 1 to 5 from the timing belt end of the engine (see illustration). Note: On some engines the flywheel/driveplate end (number 5) bearing cap may not be numbered but is easily identified anyway. If the bearing caps are not marked, using a hammer and punch Note: New main bearing cap/bridge bolts will be required on refitting. 10 Remove the oil pump and flywheel/ driveplate as described in Part C of this Chapter. 11 Remove the piston and connecting rod assemblies as described in Section 9. If no work is to be done on the pistons and connecting rods, unbolt the caps and push the pistons far enough up the bores that the connecting rods are positioned clear of the crankshaft journals. 10.8 Remove the crankshaft . . . 3510 Vauxhall/Opel Omega 10.9 . . . and lift out the upper main bearing shells from the cylinder block 2D 2D•14 General engine overhaul procedures 10.17 If the rear cap is tight, screw two M8 bolts into the cap and use them to work the cap free 10.18 Removing the crankshaft 2.5 and 3.0 litre engine shells (see illustration). Remove the flywheel/driveplate end oil seal and discard it. 19 Recover the upper bearing shells from the cylinder block, and tape them to their respective caps for safe-keeping. with a pair of grips or a slide hammer. On 2.5 and 3.0 litre engines the core plugs are screwed in position. 2 Scrape all traces of gasket from the cylinder block taking care not to damage the gasket/sealing surfaces. 3 Remove all oil gallery plugs (where fitted). The plugs are usually very tight - they may have to be drilled out, and the holes re-tapped. Use new plugs when the engine is reassembled. On 2.5 and 3.0 litre engines, it is recommended that the oil bypass valve is also removed; the valve is located behind the oil filter (a new one will be needed on refitting). To remove the bypass valve, cut a thread into the centre of the valve bore with an M10 tap; use the finishing (blunt-ended) tap to ensure the valve is threaded right up to the ball. Draw the valve out from the block using an M10 bolt and washers and a socket as a spacer (see illustrations). 4 If any of the castings are extremely dirty, all should be steam-cleaned. 5 After the castings are returned, clean all oil holes and oil galleries one more time. Flush all internal passages with warm water until the water runs clear. Dry thoroughly, and apply a light film of oil to all mating surfaces, to prevent rusting. Also oil the cylinder bores. If you have access to compressed air, use it to speed up the drying process, and to blow out all the oil holes and galleries (see illustration). 11 Cylinder block cleaning and inspection 4 Cleaning 1 Remove all external components and electrical switches/sensors from the block. For complete cleaning, the core plugs should ideally be removed. On 2.0 litre engines the core plugs are a press-fit; to remove a plug, drill a small hole then insert a self-tapping screw into the hole and pull out the plug either you can stand!), soapy water and a stiff brush. Take plenty of time, and do a thorough job. Regardless of the cleaning method used, be sure to clean all oil holes and galleries very thoroughly, and to dry all components well. Protect the cylinder bores as described above, to prevent rusting. 7 All threaded holes must be clean, to ensure accurate torque readings during reassembly. To clean the threads, run the correct-size tap into each of the holes to remove rust, corrosion, thread sealant or sludge, and to restore damaged threads. If possible, use compressed air to clear the holes of debris produced by this operation. A good alternative is to inject aerosol-applied waterdispersant lubricant into each hole, using the long spout usually supplied. Warning: Wear eye protection when cleaning out these holes in this way! 8 Apply suitable sealant to the new oil gallery plugs, and insert them into the holes in the block. Tighten them securely. 9 If the engine is not going to be reassembled right away, cover it with a large plastic bag to keep it clean; protect all mating surfaces and the cylinder bores as described above, to prevent rusting. Inspection 11.3a On 2.5 and 3.0 litre engines cut an M10 thread into the oil bypass valve . . . 6 If the castings are not very dirty, you can do an adequate cleaning job with hot (as hot as 10 Visually check the castings for cracks and corrosion. Look for stripped threads in the threaded holes. If there has been any history of internal water leakage, it may be worthwhile having an engine overhaul specialist check the cylinder block/crankcase with special equipment. If defects are found, have them repaired if possible, or renew the assembly. 11 Check the bore of each cylinder for scuffing and scoring. 12 Measure the diameter of each cylinder bore at the top (just below the wear ridge), centre and bottom of the bore, both parallel to the crankshaft axis and at right angles to it, so that a total of six measurements are taken. Note that there are various size groups of standard bore diameter to allow for manufacturing tolerances; the size group markings are stamped on the cylinder block upper surface. 13 Compare the results with the Specifications at the beginning of this 11.3b . . . then use an M10 bolt and washer and a suitable socket . . . 11.3c . . . to draw the valve assembly out from the cylinder block 11.5 Use compressed air to blow out all the cylinder block internal drillings and oilways Warning: Wear eye protection when using compressed air! 3510 Vauxhall/Opel Omega General engine overhaul procedures 2D•15 Chapter; if any measurement exceeds the service limit specified, the cylinder block must be rebored if possible, or renewed and new piston assemblies fitted. 14 If the cylinder bores are badly scuffed or scored, or if they are excessively worn, out-ofround or tapered, or if the piston-to-bore clearances is excessive (see Section 12), the cylinder block must be rebored (if possible) or renewed and new pistons fitted. Oversize (0.5 mm) pistons are available for all engines. 15 If the bores are in reasonably good condition and not worn to the specified limits, then the piston rings should be renewed. If this is the case, the bores should be honed to allow the new rings to bed in correctly and provide the best possible seal. The conventional type of hone has spring-loaded stones, and is used with a power drill. You will also need some paraffin (or honing oil) and rags. The hone should be moved up and down the bore to produce a crosshatch pattern, and plenty of honing oil should be used. Ideally, the crosshatch lines should intersect at approximately a 60° angle. Do not take off more material than is necessary to produce the required finish. If new pistons are being fitted, the piston manufacturers may specify a finish with a different angle, so their instructions should be followed. Do not withdraw the hone from the bore while it is still being turned – stop it first. After honing a bore, wipe out all traces of the honing oil. If equipment of this type is not available, or if you are not sure whether you are competent to undertake the task yourself, an engine overhaul specialist will carry out the work at moderate cost. 16 On 2.5 and 3.0 litre engines, on completion fit a new oil bypass valve to the cylinder block and tap it fully into position using a hammer and tubular drift (a 15 mm socket is ideal) (see illustrations). 12 Piston/connecting rod assembly inspection 4 1 Before the inspection process can begin, the piston/connecting rod assemblies must be cleaned, and the original piston rings removed from the pistons. 2 Carefully expand the old rings over the top of the pistons (see illustration). The use of two or three old feeler blades will be helpful in preventing the rings dropping into empty grooves. Be careful not to scratch the piston with the ends of the ring. The rings are brittle, and will snap if they are spread too far. They’re also very sharp - protect your hands and fingers. Note that the third (oil control) ring consists of a spacer and two side rails. Always remove the rings from the top of the piston. Keep each set of rings with its piston if the old rings are to be re-used. 3 Scrape away all traces of carbon from the top of the piston. A hand-held wire brush (or a 11.16a On 2.5 and 3.0 litre engines, insert the new bypass valve into the cylinder block . . . 11.16b . . . and tap it fully into position using a hammer and socket piece of fine emery cloth) can be used, once the majority of the deposits have been scraped away. The piston identification markings should now be visible. 4 Remove the carbon from the ring grooves in the piston, using an old ring. Break the ring in half to do this (be careful not to cut your fingers - piston rings are sharp). Be careful to remove only the carbon deposits - do not remove any metal, and do not nick or scratch the sides of the ring grooves. 5 Once the deposits have been removed, clean the piston/connecting rod assembly with paraffin or a suitable solvent, and dry thoroughly. Make sure that the oil return holes in the ring grooves are clear. 6 If the cylinder bores are not damaged or worn excessively, and if the cylinder block does not need to be rebored (see Section 11), check the pistons as follows. 7 Carefully inspect each piston for cracks around the skirt, around the gudgeon pin holes, and at the piston ring ‘lands’ (between the ring grooves). 8 Look for scoring and scuffing on the piston skirt, holes in the piston crown, and burned areas at the edge of the crown. If the skirt is scored or scuffed, the engine may have been suffering from overheating, and/or abnormal combustion which caused excessively high operating temperatures. The cooling and lubrication systems should be checked thoroughly. Scorch marks on the sides of the pistons show that blow-by has occurred. A hole in the piston crown, or burned areas at the edge of the piston crown, indicates that abnormal combustion (pre-ignition, knocking, or detonation) has been occurring. If any of the above problems exist, the causes must be investigated and corrected, or the damage will occur again. The causes may include incorrect ignition timing or a faulty injector. 9 Corrosion of the piston, in the form of pitting, indicates that coolant has been leaking into the combustion chamber and/or the crankcase. Again, the cause must be corrected, or the problem may persist in the rebuilt engine. 10 Measure the piston diameter at right angles to the gudgeon pin axis; compare the results with the Specifications at the beginning of this Chapter. Note that there are various size groups of standard piston diameter to allow for manufacturing tolerances; the size group markings are stamped on the piston crown. 11 To measure the piston-to-bore clearance, either measure the bore (see Section 11) and piston skirt as described and subtract the skirt diameter from the bore measurement, or insert each piston into its original bore, then select a feeler gauge blade and slip it into the bore along with the piston. The piston must be aligned exactly in its normal attitude, and the feeler gauge blade must be between the piston and bore, on one of the thrust faces, just up from the bottom of the bore. If the clearance is excessive, a new piston will be required. If the piston binds at the lower end of the bore and is loose towards the top, the bore is tapered. If tight spots are encountered as the piston/feeler gauge blade is rotated in the bore, the bore is out-of-round. 12 Repeat this procedure for the remaining pistons and cylinder bores. Any piston which is worn beyond the specified limits must be renewed. 13 Examine each connecting rod carefully for signs of damage, such as cracks around the big-end and small-end bearings. Check that the rod is not bent or distorted. Damage is highly unlikely, unless the engine has been seized or badly overheated. Detailed checking of the connecting rod assembly can only be carried out by a Vauxhall dealer or engine repair specialist with the necessary equipment. 3510 Vauxhall/Opel Omega 12.2 Using a feeler blade to remove a piston ring 2D 2D•16 General engine overhaul procedures result can be compared with the specified amount, and will give an indication as to whether new main bearing shells are required. 3 If a dial gauge is not available, feeler gauges can be used (see illustration). First push the crankshaft fully towards the flywheel/driveplate end of the engine, then use feeler gauges to measure the gap between the web of the crankpin and the side of thrustwasher which is incorporated into number 3 main bearing shells on 2.0 litre engines and number 4 shell on 2.5 and 3.0 litre engines. 12.20a Ensure the piston and connecting rod are assembled so the arrow on the piston crown (circled) is pointing away from . . . 14 On 2.0 and 2.5 litre engines, the gudgeon pins are an interference fit in the connecting rod small-end bearing. Therefore, piston and/or connecting rod renewal should be entrusted to a Vauxhall dealer or engine repair specialist, who will have the necessary tooling to remove and install the gudgeon pins. If new pistons are to be fitted, ensure that the correct size group pistons are fitted to each bore (see Section 12). Note: Vauxhall state that the piston/connecting rod assemblies should not be disassembled. If any components requires renewal, then the complete assembly must be renewed. Do not fit a new piston to an old connecting rod or vice versa. 15 On 3.0 litre engines, the gudgeon pins are of the floating type, secured in position by two circlips. On these engines, the pistons and connecting rods can be separated as follows. 16 Using a small flat-bladed screwdriver, prise out the circlips, and push out the gudgeon pin. Hand pressure should be sufficient to remove the pin. Identify the piston and rod to ensure correct reassembly. Discard the circlips - new ones must be used on refitting. 17 Examine the gudgeon pin and connecting rod small-end bearing for signs of wear or damage. Wear will require the renewal of both the pin and connecting rod. 18 The connecting rods themselves should not be in need of renewal, unless seizure or some other major mechanical failure has occurred. Check the alignment of the 13.2 Checking crankshaft endfloat with a dial gauge 12.20b . . . the assembly mark (circled) on the side of the connecting rod connecting rods visually, and if the rods are not straight, take them to an engine overhaul specialist for a more detailed check. 19 Examine all components, and obtain any new parts from your Vauxhall dealer. If new pistons are purchased, they will be supplied complete with gudgeon pins and circlips. Circlips can also be purchased individually. 20 Assemble the piston and connecting rod so that the arrow on the piston crown is pointing away from the assembly mark which is cast onto one side of the connecting rod, on the top of the big-end bore (see illustrations). 21 Apply a smear of clean engine oil to the gudgeon pin. Slide it into the piston and through the connecting rod small-end. Check that the piston pivots freely on the rod, then secure the gudgeon pin in position with two new circlips, ensuring that each circlip is correctly located in its groove in the piston. Inspection 4 Clean the crankshaft using paraffin or a suitable solvent, and dry it, preferably with compressed air if available. Be sure to clean the oil holes with a pipe cleaner or similar probe, to ensure that they are not obstructed. Warning: Wear eye protection when using compressed air. 1 If the crankshaft endfloat is to be checked, this must be done when the crankshaft is still installed in the cylinder block, but is free to move (see Section 10). 2 Check the endfloat using a dial gauge in contact with the end of the crankshaft (see illustration). Push the crankshaft fully one way, and then zero the gauge. Push the crankshaft fully the other way, and check the endfloat. The 5 Check the main and big-end bearing journals for uneven wear, scoring, pitting and cracking. 6 Big-end bearing wear is accompanied by distinct metallic knocking when the engine is running (particularly noticeable when the engine is pulling from low speed) and some loss of oil pressure. 7 Main bearing wear is accompanied by severe engine vibration and rumble - getting progressively worse as engine speed increases - and again by loss of oil pressure. 8 Check the bearing journal for roughness by running a finger lightly over the bearing surface. Any roughness (which will be accompanied by obvious bearing wear) indicates that the crankshaft requires regrinding (where possible) or renewal. 9 Check for burrs around the crankshaft oil holes (the holes are usually chamfered, so burrs should not be a problem unless regrinding has been carried out carelessly). Remove any burrs with a fine file or scraper, and thoroughly clean the oil holes as described previously. 10 Using a micrometer, measure the diameter of the main and big-end bearing journals, and compare the results with the Specifications (see illustration). By measuring the diameter 13.3 Using a feeler blade to measure crankshaft endfloat (2.0 litre engine shown) 13.10 Using a micrometer to measure a main bearing journal 13 Crankshaft inspection 4 Checking crankshaft endfloat 3510 Vauxhall/Opel Omega General engine overhaul procedures 2D•17 at a number of points around each journal’s circumference, you will be able to determine whether or not the journal is out-of-round. Take the measurement at each end of the journal, near the webs, to determine if the journal is tapered. Compare the results obtained with those given in the Specifications. If the crankshaft paint markings are still visible, the bearing journal size can be determined from these. 11 Check the oil seal contact surfaces at each end of the crankshaft for wear and damage. If the seal has worn a deep groove in the surface of the crankshaft, consult an engine overhaul specialist; repair may be possible, but otherwise a new crankshaft will be required. 12 Set the crankshaft up in V-blocks, and position a dial gauge on the top of the crankshaft number 1 main bearing journal. Zero the dial gauge, then slowly rotate the crankshaft through two complete revolutions, noting the journal run-out. Repeat the procedure on the remaining main bearing journals, so that a run-out measurement is available for all main bearing journals. If the difference between the run-out of any two journals exceeds the service limit given in the Specifications, the crankshaft must be renewed. 13 Undersize big-end and main bearing shells are produced by Vauxhall for all engines. If the crankshaft journals have not already been reground, it may be possible to have the crankshaft reconditioned, and to fit undersize shells. Main bearing shells are available in 0.25 and 0.50 mm undersizes and the big-end bearing shells are available in 0.25 and 0.50 mm undersizes for the 2.5 and 3.0 litre engines and 0.25 mm undersize for 2.0 litre engine. 14 Main and big-end bearings inspection 14.1 Typical main bearing shell identification marking general position as their location in the engine. This will enable you to match any bearing problems with the corresponding crankshaft journal. 4 Dirt and other foreign matter gets into the engine in a variety of ways. It may be left in the engine during assembly, or it may pass through filters or the crankcase ventilation system. It may get into the oil, and from there into the bearings. Metal chips from machining operations and normal engine wear are often present. Abrasives are sometimes left in engine components after reconditioning, especially when parts are not thoroughly cleaned using the proper cleaning methods. Whatever the source, these foreign objects often end up embedded in the soft bearing material, and are easily recognised. Large particles will not embed in the bearing, and will score or gouge the bearing and journal. The best prevention for this cause of bearing failure is to clean all parts thoroughly, and keep everything spotlessly-clean during engine assembly. Frequent and regular engine oil and filter changes are also recommended. 5 Lack of lubrication (or lubrication 4 1 Even though the main and big-end bearings should be renewed during the engine overhaul, the old bearings should be retained for close examination, as they may reveal valuable information about the condition of the engine. The identification number stamped on the rear of the bearing shells can be used by a Vauxhall dealer to identify the size group of the bearing (see illustration). 2 Bearing failure can occur due to lack of lubrication, the presence of dirt or other foreign particles, overloading the engine, or corrosion (see illustration). Regardless of the cause of bearing failure, the cause must be corrected (where applicable) before the engine is reassembled, to prevent it from happening again. 3 When examining the bearing shells, remove them from the cylinder block, the main bearing caps, the connecting rods and the connecting rod big-end bearing caps. Lay them out on a clean surface in the same breakdown) has a number of interrelated causes. Excessive heat (which thins the oil), overloading (which squeezes the oil from the bearing face) and oil leakage (from excessive bearing clearances, worn oil pump or high engine speeds) all contribute to lubrication breakdown. Blocked oil passages, which usually are the result of misaligned oil holes in a bearing shell, will also oil-starve a bearing, and destroy it. When lack of lubrication is the cause of bearing failure, the bearing material is wiped or extruded from the steel backing of the bearing. Temperatures may increase to the point where the steel backing turns blue from overheating. 6 Driving habits can have a definite effect on bearing life. Full-throttle, low-speed operation (labouring the engine) puts very high loads on bearings, tending to squeeze out the oil film. These loads cause the bearings to flex, which produces fine cracks in the bearing face (fatigue failure). Eventually, the bearing material will loosen in pieces, and tear away from the steel backing. 7 Short-distance driving leads to corrosion of bearings, because insufficient engine heat is produced to drive off the condensed water and corrosive gases. These products collect in the engine oil, forming acid and sludge. As the oil is carried to the engine bearings, the acid attacks and corrodes the bearing material. 8 Incorrect bearing installation during engine assembly will lead to bearing failure as well. Tight-fitting bearings leave insufficient bearing running clearance, and will result in oil starvation. Dirt or foreign particles trapped behind a bearing shell result in high spots on the bearing, which lead to failure. 9 As mentioned at the beginning of this Section, the bearing shells should be renewed as a matter of course during engine overhaul; to do otherwise is false economy. 15 Engine overhaul reassembly sequence 14.2 Typical bearing failures 3510 Vauxhall/Opel Omega 1 Before reassembly begins, ensure that all new parts have been obtained, and that all necessary tools are available. Read through the entire procedure to familiarise yourself with the work involved, and to ensure that all items necessary for reassembly of the engine are at hand. In addition to all normal tools and materials, thread-locking compound will be needed. A good quality tube of liquid sealant will also be required for the joint faces that are fitted without gaskets (the numbers of the Vauxhall recommended sealants are given in the text). 2 In order to save time and avoid problems, engine reassembly can be carried out in the following order: a) Crankshaft. b) Piston/connecting rod assemblies. c) Oil pump. 2D 2D•18 General engine overhaul procedures its groove. Check the ring-to-groove clearance of each ring using feeler gauges and check that the clearance is within the specified range then position the ring end gaps as shown (see illustrations). 17 Crankshaft refitting and main bearing running clearance check 16.4 Measuring a piston ring end gap using a feeler gauge d) e) f) g) Sump. Flywheel/driveplate. Cylinder head(s). Timing belt tensioner and sprockets, and belts. h) Inlet and exhaust manifolds (Chapter 4A). i) Engine external components. 3 At this stage, all engine components should be absolutely clean and dry, with all faults repaired. The components should be laid out (or in individual containers) on a completely clean work surface. 16 Piston rings refitting 4 1 Before fitting new piston rings, the ring end gaps must be checked as follows. 2 Lay out the piston/connecting rod assemblies and the new piston ring sets, so that the ring sets will be matched with the same piston and cylinder during the end gap measurement and subsequent engine reassembly. 3 Insert the top ring into the first cylinder, and push it down the bore using the top of the piston. This will ensure that the ring remains square with the cylinder walls. Push the ring 16.11b Piston ring end gap positions I Top and second compression rings II Oil control ring side rails 16.11a Checking the piston ring-to-groove clearance using a feeler gauge down into the bore until it is positioned 15 to 20 mm down from the top edge of the bore, then withdraw the piston. 4 Measure the end gap using feeler gauges, and compare the measurements with the figures given in the Specifications (see illustration). 5 If the gap is too small (unlikely if genuine Vauxhall parts are used), it must be enlarged, or the ring ends may contact each other during engine operation, causing serious damage. Ideally, new piston rings providing the correct end gap should be fitted. As a last resort, the end gap can be increased by filing the ring ends very carefully with a fine file. Mount the file in a vice with soft jaws, slip the ring over the file with the ends contacting the file face, and slowly move the ring to remove material from the ends. Take care, as piston rings are sharp, and are easily broken. 6 With new piston rings, it is unlikely that the end gap will be too large. If the gaps are too large, check that you have the correct rings for your engine and for the particular cylinder bore size. 7 Repeat the checking procedure for each ring in the first cylinder, and then for the rings in the remaining cylinders. Remember to keep rings, pistons and cylinders matched up. 8 Once the ring end gaps have been checked and if necessary corrected, the rings can be fitted to the pistons. 9 Fit the piston rings using the same technique as for removal. Fit the bottom (oil control) spacer first then install both the side rails, noting that both the spacer and side rails can be installed either way up. 10 The second and top compression rings are different and can be identified by their cross-sections; the top ring is square whilst the second ring is tapered. Fit the second and top compression rings ensuring that each ring is fitted the correct way up with its identification (TOP) mark uppermost. Note: Always follow any instructions supplied with the new piston ring sets - different manufacturers may specify different procedures. Do not mix up the top and second compression rings. On some engines the top ring will not have an identification marking and can be fitted either way up. 11 With the piston rings correctly installed, check that each ring is free to rotate easily in 3510 Vauxhall/Opel Omega 4 Note: It is recommended that new main bearing shells are fitted regardless of the condition of the original ones. Selection of bearing shells 1 Although the original bearing shells fitted at the factory maybe of various grades, all replacement bearing shells sold are of the same grade. Vauxhall supply both standard size bearing shells and undersize shells for use when the crankshaft has been reground. The required size of shell required can be determined by measuring the crankshaft journals (see Section 13). Main bearing running clearance check 2 Clean the backs of the bearing shells and the bearing locations in both the cylinder block and the main bearing caps. 3 Press the bearing shells into their locations, ensuring that the tab on each shell engages in the notch in the cylinder block or main bearing cap (see illustration). If the original bearing shells are being used for the check ensure they are refitted in their original locations. When fitting new shells on 2.5 and 3.0 litre engines, note that No1 bearing is wider than No2 and 3 and that the grooved shell of No2 and 3 bearing should be fitted in the upper location. The clearance can be checked in either of two ways. 4 One method (which will be difficult to achieve without a range of internal micrometers or internal/external expanding calipers) is to refit the main bearing caps to the cylinder block, with bearing shells in place. With the cap retaining bolts correctly tightened (use the original bolts for the check, not the new ones), measure the internal diameter of each assembled pair of bearing 17.3 Fit each main bearing shell making sure its tab is correctly seated in the notch (arrowed) General engine overhaul procedures 2D•19 17.7 Plastigauge in place on a crankshaft journal 17.10 Measure the width of the crushed Plastigauge using the scale on the card provided shells. If the diameter of each corresponding crankshaft journal is measured and then subtracted from the bearing internal diameter, the result will be the main bearing running clearance. 5 The second (and more accurate) method is to use a product known as Plastigauge. This consists of a fine thread of perfectly round plastic which is compressed between the bearing shell and the journal. When the shell is removed, the plastic is deformed and can be measured with a special card gauge supplied with the kit. The running clearance is determined from this gauge. Plastigauge is sometimes difficult to obtain but enquiries at one of the larger specialist quality motor factors should produce the name of a stockist in your area. The procedure for using Plastigauge is as follows. 6 With the main bearing upper shells in place, carefully lay the crankshaft in position. Do not use any lubricant; the crankshaft journals and bearing shells must be perfectly clean and dry. 7 Cut several lengths of the appropriate size Plastigauge (they should be slightly shorter than the width of the main bearings) and place one length on each crankshaft journal axis (see illustration). 8 With the main bearing lower shells in position, refit the main bearing caps, using the identification marks to ensure each one is correctly positioned. On 2.5 and 3.0 litre engines also refit the main bearing bridge casting ensuring the arrow cast on it is pointing towards the timing belt end of the engine. 9 Refit the original main bearing retaining bolts and tighten them to the specified stage 1 torque and then through the stage 2 and 3 angles (see paragraphs 22 and 23). Take care not to disturb the Plastigauge and do not rotate the crankshaft at any time during this operation. Evenly and progressively slacken and remove the main bearing cap bolts then lift off the caps again taking great care not to disturb the Plastigauge or rotate the crankshaft. 10 Compare the width of the crushed Plastigauge on each journal to the scale printed on the Plastigauge envelope to obtain the main bearing running clearance (see illustration). Compare the clearance measured with that given in the Specifications at the start of this Chapter. 17.15 Crankshaft sensor rotor is secured to the crankshaft by four bolts (three arrowed) 11 If the clearance is significantly different from that expected, the bearing shells may be the wrong size (or excessively worn if the original shells are being re-used). Before deciding that the crankshaft is worn, make sure that no dirt or oil was trapped between the bearing shells and the caps or block when the clearance was measured. If the Plastigauge was wider at one end than at the other, the crankshaft journal may be tapered. 12 Before condemning the components concerned, seek the advice of your Vauxhall dealer or suitable engine repair specialist. They will also be able to inform as to the best course of action or whether renewal will be necessary. 13 Where necessary, obtain the correct size of bearing shell and repeat the running clearance checking procedure as described above. 14 On completion, carefully scrape away all traces of the Plastigauge material from the crankshaft and bearing shells using a fingernail or other object which is unlikely to score the bearing surfaces. Final crankshaft refitting 2.0 litre engine 15 Carefully lift the crankshaft out of the cylinder block once more. If a new crankshaft is being fitted, do not forget to transfer the crankshaft sensor rotor over from the original crankshaft to the new one. Secure the rotor in position with new retaining bolts, tightening them to the specified torque (see illustration). 16 Place the bearing shells in their locations as described above in paragraphs 2 and 3 (see illustration). If new shells are being fitted, ensure that all traces of the protective grease are cleaned off using paraffin. Wipe dry the shells and caps with a lint-free cloth. 17.16 The bearing shells which incorporate the thrust flanges (A) must be fitted to the centre (No 3) bearing on 2.0 litre engines and the rear (No 4) bearing on 2.5 and 3.0 litre engine. All other shells have no flanges (B) 3510 Vauxhall/Opel Omega 2D 2D•20 General engine overhaul procedures 17.17 Lubricate the upper bearing shells with clean engine oil then lower the crankshaft into position 17.19 Refit the bearing caps number 1 to 4 ensuring each one is refitted in its original location 17.20 Fill the side grooves of the rear (number 5) bearing cap with sealant prior to refitting it to the engine 17 Lubricate the upper shells with clean engine oil then lower the crankshaft into position (see illustration). 18 Ensure the crankshaft is correctly seated then check the endfloat as described in Section 13. 19 Ensure the bearing shells are correctly located in the caps and refit the caps number 1 to 4 to the cylinder block (see illustration). Ensure the caps are fitted in their correct locations, with number 1 cap at the timing belt end. 20 Ensure the rear (number 5) bearing cap is clean and dry then fill the groove on each side of the cap with sealing compound (Vauxhall recommend the use of sealant 15 03 295 available from your Vauxhall dealer) (see illustration). Fit the bearing cap to the engine, ensuring it is fitted the correct way around. bolts to the casting centre retaining holes (the outer bolts are fitted later with the baffle plate) and tighten them first to the specified stage 1 torque setting then tighten them through the specified stage 2 angle. 27 On all engines refit/reconnect the piston connecting rod assemblies to the crankshaft as described in Section 18. 28 Referring to Part A (SOHC engine) or Part B (DOHC engine), fit a new crankshaft oil seal then refit the flywheel/driveplate, oil pump, cylinder head, timing belt sprocket(s) and fit a new timing belt. 17.21 Lubricate the threads of the new main bearing cap bolts . . . 21 Apply a smear of clean engine to oil to the threads and underneath the heads of the new main bearing cap bolts. Fit the bolts tightening them all by hand (see illustration). 22 Working in a diagonal sequence from the centre outwards, tighten the main bearing cap bolts to the specified Stage 1 torque setting (see illustration). 23 Once all bolts are tightened to the specified Stage 1 torque, go around again and tighten all bolts through the specified Stage 2 angle then go around for once more and tighten all bolts through the specified Stage 3 angle. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy (see illustration). If a gauge is not available, use white paint to make alignment marks between the bolt head and cap prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 24 Once all the bolts have been tightened, inject more sealant down the grooves in the rear main bearing cap until sealant is seen to be escaping through the joints. Once you are sure the cap grooves are full of sealant, wipe off all excess sealant using a clean cloth. 25 Check that the crankshaft is free to rotate smoothly; if excessive pressure is required to turn the crankshaft, investigate the cause before proceeding further. 26 On earlier DOHC engines with a two-piece sump, ensure the mating surfaces are clean and dry then refit the main bearing ladder casting to the block. Fit the new retaining 17.22 . . . then tighten the bolts to the specified stage 1 torque setting . . . 17.23 . . . and then through the specified stage 2 and 3 angles 3510 Vauxhall/Opel Omega 2.5 and 3.0 litre petrol engines 29 Refit the crankshaft as described in paragraphs 15 to 18. 30 Ensure the bearing shells are correctly located in the caps and refit the caps number 1 to 3 to the cylinder block (see illustration). Ensure the caps are fitted in their correct locations, with number 1 cap at the timing belt end. 31 Ensure the rear bearing cap is clean and dry then fill the groove on each side of the cap with sealing compound (Vauxhall recommend the use of sealant 15 03 295 - available from your Vauxhall dealer). Fit the bearing cap to the engine, ensuring it is fitted the correct way around (see illustrations). 32 Back off the threaded sleeves until they no longer protrude from the main bearing bridge casting then refit the casting, making sure the arrow is pointing towards the timing belt end of the engine (see illustration). 17.30 Refit the bearing caps number 1 to 3 ensuring each one is refitted in its original location General engine overhaul procedures 2D•21 17.31a Fill the side grooves of the rear (number 4) bearing cap with sealant . . . 17.31b . . . then refitting it to the cylinder block 17.32 Refit the main bearing bridge casting making sure the arrow (circled) is pointing towards the timing belt end of the engine 17.33 Lubricate the threads of the new main bearing cap bolts . . . 17.34 . . . then tighten the bolts to the specified stage 1 torque setting . . . 17.35 . . . and then through the specified stage 2 and 3 angles 33 Apply a smear of clean engine to oil to the threads and underneath the heads of the new main bearing cap bolts (see illustration). Fit the bolts tightening them all by hand. 34 Working in a diagonal sequence from the 17.36 Inject sealant down each of the rear main bearing cap grooves until it is seen to be escaping through the joints (arrowed) centre outwards, evenly and progressively tighten the main bearing cap bolts to the specified Stage 1 torque setting (see illustration). 35 Once all bolts are tightened to the specified Stage 1 torque, go around again and tighten all bolts through the specified Stage 2 angle then go around for once more and tighten all bolts through the specified Stage 3 angle. It is recommended that an anglemeasuring gauge is used during the final stages of the tightening, to ensure accuracy (see illustration). If a gauge is not available, use white paint to make alignment marks between the bolt head and cap prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 36 Once all the bolts have been tightened, inject more sealant down the grooves in the rear main bearing cap until sealant is seen to be escaping through the joints (see illustration). Once you are sure the cap grooves are full of sealant, wipe off all excess sealant using a clean cloth. 37 Check that the crankshaft is free to rotate smoothly; if excessive pressure is required to turn the crankshaft, investigate the cause before proceeding further. 38 Tighten the threaded sleeves to the main bearing bridge casting and tighten them to the specified torque. Once the sleeves are tight, refit the bolts securing the casting to the cylinder block and tighten them to the specified torque (see illustrations). 39 Refit/reconnect the piston connecting rod assemblies to the crankshaft as described in Section 18. 40 Referring to Part C, fit a new crankshaft oil seal then refit the flywheel/driveplate, oil pump, cylinder heads, timing belt sprockets and fit a new timing belt. 17.38a Tighten the main bearing bridge casting threaded sleeves (arrowed) to the specified torque . . . 17.38b . . . then refit the bolts securing the casting to the cylinder block . . . 17.38c . . . and tighten them (arrowed) to their specified torque setting 3510 Vauxhall/Opel Omega 2D 2D•22 General engine overhaul procedures 18.3 Fit the bearing shells to the connecting rod and cap making sure their tabs are correctly seated in the cutouts 18 Piston/connecting rod assembly - refitting and bigend running clearance check 4 Note: It is recommended that new piston rings and big-end bearing shells are fitted regardless of the condition of the original ones. Selection of bearing shells 1 Although the original bearing shells fitted at the factory maybe of various grades, all replacement bearing shells sold are of the same grade. Vauxhall supply both standard size bearing shells and undersize shells for use when the crankshaft has been reground. The required size of shell required can be determined by measuring the crankshaft journals (see Section 13). Big-end bearing running clearance check 2 Clean the backs of the bearing shells and the bearing locations in both the connecting rod and bearing cap. 3 Press the bearing shells into their locations, ensuring that the tab on each shell engages in the notch in the connecting rod and cap (see 18.8 Ensure the piston ring end gaps are correctly positioned then clamp them in position with a ring compressor illustration). If the original bearing shells are being used for the check ensure they are refitted in their original locations. The clearance can be checked in either of two ways. 4 One method is to refit the big-end bearing cap to the connecting rod, with bearing shells in place. With the cap retaining bolts (use the original bolts for the check) correctly tightened, use an internal micrometer or vernier caliper to measure the internal diameter of each assembled pair of bearing shells. If the diameter of each corresponding crankshaft journal is measured and then subtracted from the bearing internal diameter, the result will be the big-end bearing running clearance. 5 The second method is to use Plastigauge as described in Section 17, paragraphs 5 to 14. Place a strand of Plastigauge on each (cleaned) crankpin journal and refit the (clean) piston/connecting rod assemblies, shells and big-end bearing caps. Tighten the bolts (see paragraphs 13 - use the original bolts for the check) correctly taking care not to disturb the Plastigauge. Dismantle the assemblies without rotating the crankshaft and use the scale printed on the Plastigauge envelope to obtain the big-end bearing running clearance. On completion of the measurement, carefully scrape off all traces of Plastigauge from the journal and shells using a fingernail or other object which will not score the components. position with a piston ring compressor (see illustration). 9 Insert the piston/connecting rod assembly into the top of cylinder No 1, ensuring that the arrow marking on the piston crown is pointing towards the timing belt end of the engine. Using a block of wood or hammer handle against the piston crown, tap the assembly gently (do not force it) into the cylinder until the piston crown is flush with the top of the cylinder (see illustration). As the piston is fitted make sure the connecting rod lower end remains correctly aligned with the crankshaft to avoid damage. 10 Taking care not to mark the cylinder bore, liberally lubricate the crankpin and both bearing shells, then pull the piston/connecting rod assembly down the bore and onto the crankpin. 11 Ensure the connecting rod and bearing cap mating surfaces are completely clean and dry; this is most important on engines where the bearing caps are ‘cracked’ off of the rod. 12 Refit the big-end bearing cap, using the markings to ensure it is fitted the correct way around (the lug on the bearing cap base should be facing the flywheel/driveplate end of the engine), then screw in the new retaining bolts (see illustrations). Final piston/connecting rod assembly refitting 18.9 Insert the piston into the correct bore, tapping it gently into position with the handle of a hammer 6 Ensure the bearing shells are correctly refitted as described above in paragraphs 2 and 3. If new shells are being fitted, ensure that all traces of the protective grease are cleaned off using paraffin. Wipe dry the shells and connecting rods with a lint-free cloth. 7 Lubricate the bores, the pistons and piston rings then lay out each piston/connecting rod assembly in its respective position. 8 Starting with assembly number 1, make sure that the piston rings are still spaced as described in Section 16, then clamp them in 3510 Vauxhall/Opel Omega 18.12a Refit the bearing cap making sure the lug is facing towards the flywheel/driveplate end of the engine . . . General engine overhaul procedures 2D•23 18.12b . . . and screw in the new retaining bolts 18.13a Tighten both bolts to the specified stage 1 torque setting . . . 13 Tighten both bearing cap bolts to the specified Stage 1 torque setting then tighten them through the specified Stage 2 angle, and finally through the specified Stage 3 angle. It is recommended that an angle-measuring gauge is used during the final stages of the tightening, to ensure accuracy (see illustrations). If a gauge is not available, use white paint to make alignment marks between the bolt head and cap prior to tightening; the marks can then be used to check that the bolt has been rotated through the correct angle. 14 Refit the remaining piston and connecting rod assemblies in the same way. 15 Rotate the crankshaft, and check that it turns freely, with no signs of binding or tight spots. 16 On 2.0 litre SOHC engines, working as described in Part A of this Chapter, fit the baffle plate, oil pump pick-up/strainer and sump to the cylinder block then refit the cylinder head. 17 On 2.0 litre DOHC engines carry out the following: a) On early (pre 1998 model year) engines with a two-piece sump, refit the baffle plate to the main bearing ladder casting and screw in the new retaining bolts. Working in a diagonal sequence from the centre outwards, tighten the bolts first to the specified stage 1 torque and then tighten them through the specified stage 2 angle. b) On later engines refit the crankshaft balancer unit as described in Part B. c) On all engines refit the oil pump pickup/strainer and sump then refit the cylinder head as described in Part B. 18 On 2.5 and 3.0 litre engines refit the baffle plate to the base of the main bearing bridge casting and tighten its retaining bolts to the specified torque (see illustration). Working as described in Part C of this Chapter, refit the sump then install the cylinder heads. 18.13b . . . then tighten them through the specified stage 2 and 3 angles 19 Engine initial start up after overhaul 1 With the engine refitted in the vehicle, double-check the engine oil and coolant levels. Make a final check that everything has been reconnected, and that there are no tools or rags left in the engine compartment. 2 Ensure the ignition is switched off then disable the ignition system by disconnecting the wiring connector from the DIS module (see Chapter 5A) and the fuel system by removing the fuel pump relay from the engine compartment relay box (see Chapter 4A, Section 13). 3 Turn the engine on the starter until the oil pressure warning light goes out then stop. Ensure the ignition is switched off then securely refit the relay and reconnect the wiring connector. 4 Start the engine as normal noting that this may take a little longer than usual, due to the fuel system components having been disturbed. 3510 Vauxhall/Opel Omega 18.18 On 2.5 and 3.0 litre engines, refit the baffle plate and tighten its retaining bolts to the specified torque 5 While the engine is idling, check for fuel, water and oil leaks. Don’t be alarmed if there are some odd smells and smoke from parts getting hot and burning off oil deposits. 6 Assuming all is well, keep the engine idling until hot water is felt circulating through the top hose, then switch off the engine. 7 Allow the engine to cool then recheck the oil and coolant levels as described in Weekly checks, and top-up as necessary. 8 If new pistons, rings or crankshaft bearings have been fitted, the engine must be treated as new, and run-in for the first 500 miles (800 km). Do not operate the engine at full-throttle, or allow it to labour at low engine speeds in any gear. It is recommended that the oil and filter be changed at the end of this period. 2D 3•1 Chapter 3 Cooling, heating and ventilation systems Contents Air conditioning system - description and precautions . . . . . . . . . . . 11 Air conditioning system components - removal and refitting . . . . . . 12 Antifreeze mixture - general . . . . . . . . . . . . . . . . . . .See Weekly checks Blower motor and series resistor - removal and refitting . . . . . . . . . 10 Coolant pump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 5 Cooling system - draining, flushing and refilling . . . . . . .see Chapter 1 Electric cooling fans - removal and refitting . . . . . . . . . . . . . . . . . . . 3 Electronic Climate Control (ECC) components - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Expansion tank - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 6 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Heater control system components - removal and refitting . . . . . . . 8 Heater matrix - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 9 Pollen filter - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . .see Chapter 1 Radiator - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Temperature gauge sender unit - removal and refitting . . . . . . . . . . 7 Thermostat - removal, testing and refitting . . . . . . . . . . . . . . . . . . . . 4 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications System type All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pressurised, with cross-flow radiator, centrifugal water pump driven by timing belt, bypass thermostat, and remote expansion tank. Thermostatically controlled electric main cooling fan, with one or two auxiliary electric cooling fans, depending on specification. Thermostat Opening commences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fully open . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92ºC (198ºF) 107ºC (225ºF) Coolant Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Refer to Weekly checks Refer to Chapter 1 3510 Vauxhall/Opel Omega 3 3•2 Cooling, heating and ventilation systems Torque wrench settings Nm lbf ft 35 20 26 15 All models Air conditioning compressor: Front mounting bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear mounting bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air conditioning refrigerant lines unions: To bulkhead flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . To compressor (M10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . To condenser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . To expansion valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . To pulsation damper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . To receiver/dryer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air conditioning tri-switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coolant pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering column bracing strut: To steering column . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . To floorpan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 40 20 9 27 20 7 25 15 30 15 7 20 15 5 28 22 22 16 16 4-cylinder models Coolant pipe to thermostat cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Temperature gauge sender unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thermostat housing cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 11 15 6 8 11 6-cylinder models Coolant bridge to cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coolant intake pipe to cylinder block . . . . . . . . . . . . . . . . . . . . . . . . . . . Coolant intake pipe to exhaust manifold . . . . . . . . . . . . . . . . . . . . . . . . Coolant pipe to cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Temperature gauge sender unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thermostat housing cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 20 6 25 18 20 22 15 4 18 13 15 1 General description 1 The cooling system comprises a radiator, timing belt driven coolant pump (depending on engine), a waxstat-type bypass thermostat, and a remotely-mounted plastic expansion tank. A thermostatically-controlled electric cooling fan is fitted to all models, between the front of the engine and the radiator. An auxiliary cooling fan is also fitted, in front of the radiator. Models with air conditioning also have a second electric auxiliary cooling fan, to cope with the extra demand of cooling the refrigerant condenser. 2 Cold water from the coolant pump is forced around the cylinder block, cylinder head and heater matrix during the warm up cycle. When 2.2 Lift out the radiator upper cover panel the engine reaches a predetermined temperature, the thermostat starts to open and the coolant then circulates through the radiator via a transfer pipe, to provide extra cooling. The main cooling fan is controlled by the temperature of air behind the radiator. 2 Radiator removal and refitting 3 Removal Models with 6-cylinder engines 1 Ensure that the engine has cooled completely before starting work. Drain the cooling system as described in Chapter 1. 2 Remove the screws and lift out the radiator upper cover panel (see illustration). 2.5a Disconnect the wiring from cooling fan thermo-switches . . . 3510 Vauxhall/Opel Omega 3 Disconnect the negative and positive cables from the battery terminals, then remove the battery as described in Chapter 5A. 4 Refer to Chapter 4A and remove multi-ram air intake pre-volume chamber. 5 Disconnect the wiring from cooling fan thermo-switches, secondary air-cut-off valve, and auxiliary coolant pump (as applicable) (see illustrations). Label each connector carefully, to aid correct refitting. 6 Disconnect all coolant hoses from the radiator; these include the expansion tank hose, the radiator top and bottom hoses, and the auxiliary coolant pump hose (where applicable) (see illustrations). 7 Release the securing clips and disconnect the air hoses from secondary air cut-off valve. 8 On models with air conditioning, unscrew the securing bolts and disconnect the refrigerant condenser from radiator (see illustration). 2.5b . . . secondary air-cut-off valve . . . Cooling, heating and ventilation systems 3•3 2.5c . . . and auxiliary coolant pump 2.6c Disconnect the coolant expansion tank hose from the radiator 9 On models with automatic transmission, release the hose clips and disconnect the narrow bore hoses from the transmission fluid cooler (see illustration). Plug the pipes to prevent excessive fluid loss and the ingress of debris. 10 Release the spring clips at the top of the radiator, then withdraw radiator complete with the cooling fan from engine compartment (see illustrations). Models with 4-cylinder engines 11 Ensure that the engine has cooled completely before starting work. Drain the cooling system as described in Chapter 1. 12 Disconnect the negative cable from the battery and position it away from the terminal. 13 Disconnect the wiring from main cooling fans and is associated thermo-switch. Label the connector(s), to aid correct refitting. 2.6a Disconnect the top hose from the radiator 2.6b Disconnect the bottom hose from the engine coolant transfer pipe 2.8 Unscrew the securing bolts and disconnect the air conditioning refrigerant condenser from radiator 2.9 Disconnect the narrow bore transmission fluid cooler hoses from the radiator 14 Disconnect all coolant hoses from the radiator, including the expansion tank hose, and the radiator top and bottom hoses. 15 On models with air conditioning, undo the screws and disconnect the refrigerant heat exchanger from radiator. 16 On models with automatic transmission, release the hose clips and disconnect the narrow bore pipes from the transmission fluid cooler. Plug the pipes to prevent excessive fluid loss and the ingress of debris. 17 Release the spring clips at the top of the radiator, then withdraw radiator complete with the cooling fan from engine compartment. b) On models with automatic transmission, use new union seals when reconnecting the automatic transmission fluid cooler pipes. c) On models with air conditioning, secure the heat exchanger to the base of the radiator and tighten the retaining bolts securely. d) Refill the cooling system as described in Chapter 1. e) Where applicable, top up the level of automatic transmission fluid as described in Chapter 1. Refitting 3 Electric cooling fan(s) removal and refitting 18 Refitting is a reversal of the removal procedure, noting the following points:. a) Ensure that all coolant hose clips are securely tightened. 2 Main cooling fan Removal Models with 4-cylinder engines 2.10a Release the spring clips at the top of the radiator . . . 2.10b . . . then withdraw radiator complete with the cooling fan from engine compartment 3510 Vauxhall/Opel Omega 1 Disconnect the battery negative cable and position it away from the terminal. 2 Unplug the wiring from the rear of the fan motor, at the connector. 3 Remove the two screws that secure the fan/cowling assembly to the rear of the radiator. 4 Disengage the fan housing from its lower mounting, then lift the fan and housing from of the engine bay, taking care not to damage the cooling fins of the radiator (and airconditioning heat exchanger, where fitted). 5 The fan motor can be separated from the 3 3•4 Cooling, heating and ventilation systems 3.12 Slacken and remove the securing screws . . . housing by slackening and removing the three securing nuts. Removal Models with 6-cylinder engines 6 Disconnect the negative and positive cables from the battery terminals, then remove the battery as described in Chapter 5A. 7 Release the mounting bracket and detach secondary air cut-off valve from the fan housing. 8 Remove the screws and lift off the radiator upper cover panel. 9 Refer to Chapter 4A and remove multi-ram air intake pre-volume chamber. 10 Disconnect the wiring from the rear of the fan motor. Label each connector carefully, to aid correct refitting. 11 Release the mounting bracket and detach the auxiliary coolant pump from the side of the fan housing (where applicable). 3.13 . . . and remove the cooling fan together with its housing from the radiator (shown with radiator removed for clarity) 12 Remove the three screws that secure the fan/cowling assembly to the rear of the radiator (see illustration). 13 Disengage the fan housing from its lower mounting, then lift the fan and housing from of the engine bay, taking care not to damage the cooling fins of the radiator (and airconditioning heat exchanger, where fitted) (see illustration). 14 The fan motor can be separated from the housing by slackening and removing the three securing nuts (see illustration). Refitting (all models) 15 Refit the cooling fan by following the removal procedure in reverse. Auxiliary cooling fan(s) 3.14 Fan motor securing nuts (arrowed) 17 With reference to Chapter 11, remove the radiator grille, then unbolt and remove the cross-member from the front of the engine compartment. 18 Undo the securing screws and detach the air intake duct from the crossmember (see illustration). 19 Unclip the cover panel then unplug the wiring harness from the auxiliary fan at the multi-way connector. Release the harness from the cable ties (see illustrations). 20 To improve access, unclip the wiring harness conduit from the bodywork (see illustration). 21 Slacken and remove the securing screws then withdraw the fan and motor from its housing (see illustrations). Refitting 16 Disconnect the battery negative cable and position it away from the terminal. Refitting 22 Refitting is a reversal of removal. 3.18 Undo the securing screws and detach the air intake duct from the crossmember 3.19a Unclip the cover panel . . . 3.19b . . . then unplug the wiring harness from the auxiliary fan at the multi-way connector 3.20 Unclip the wiring harness conduit from the bodywork 3.21a Slacken and remove the securing screws . . . 3.21b . . . then withdraw the fan and motor from its housing 3510 Vauxhall/Opel Omega Cooling, heating and ventilation systems 3•5 4 Thermostat removal, testing and refitting 3 Models with 4-cylinder engines Removal 1 Drain the cooling system as described in Chapter 1. 2 Loosen the clip and disconnect the coolant hose from the thermostat housing cover. 3 Unscrew the bolts and remove the cover. Note that the thermostat is integral with the cover. 4 Carefully clean the mating surface of the thermostat housing. Refitting 5 Refitting is a reversal of the removal procedure. Use a new thermostat housing cover sealing ring and ensure that the securing screws are tightened to the specified torque. On completion, refill the cooling system as described in Chapter 1. Models with 6-cylinder engines Removal 6 Drain the cooling system as described in Chapter 1. 7 Release the clip and disconnect the radiator top hose from the engine coolant transfer pipe. 8 Slacken and remove the bolt securing the coolant transfer pipe to the cylinder head. Note that this bolt also secures one of the engine lifting eyelets and the dipstick tube. 9 Carefully pull the coolant transfer pipe from the thermostat housing, using just enough effort to disengage the O-ring seals (see illustrations). 10 Remove the upper half of the inlet manifold, with reference to Chapter 4A. 11 Unscrew the bolts and remove the cover. Note that the thermostat is integral with the cover (see illustration). Refitting 12 Refitting is a reversal of the removal procedure, noting the following points (see illustration):. a) Fit a new sealing ring to the thermostat cover. b) Ensure that the thermostat cover securing screws are tightened to the specified torque. c) Use new O-ring seals when refitting the coolant transfer pipe to the thermostat housing. d) On completion, refill the cooling system as described in Chapter 1. 4.9a Carefully pull the coolant transfer pipe from the thermostat housing . . . 4.9b . . . using just enough effort to disengage the O-ring seals thermostat begins to open. If a suitably graduated thermometer is available, the temperature at which the thermostat begins to open may be determined and then compared with the figure given in the Specifications. Note that as tap water begins to boil as its temperature approaches 100º, it will not be possible to test the thermostat in its fully open position. Using additives to raise the boiling point of the water may adversely affect the operation of thermostat, hence this is not recommended. 14 A thermostat which fails to close as the water cools must also be considered faulty and should be renewed. the fitted position of each bolt to ensure correct refitting. 5 Lift the coolant pump away from the engine and recover the seal. 5 Coolant pump removal and refitting 4 Models with 4-cylinder engines Removal 1 Drain the cooling system as described in Chapter 1. 2 Remove the camshaft timing belt tensioner pulley, as described in Chapter 2A/B. 3 Release the crankshaft sensor wiring from the timing belt cover, noting its routing ensure correct refitting. 4 Progressively slacken and remove the water pump retaining bolts. Note that the bolts are of different lengths; make a note of Refitting 6 Refit the coolant pump by following the removal procedure in reverse, noting these points:. a) Use a new coolant pump sealing ring. b) Coat the new sealing ring and the pump mating surface with silicon grease before fitting. c) The lug on the side of the coolant pump flange must be aligned with the corresponding recess in the cylinder block. d) Tighten the coolant pump securing bolts to the specified torque. e) Refit the timing belt tensioner pulley, according to the information given in Chapter 2A/B (as applicable). f) On completion, refill the cooling system with the specified quantity of correctlymixed coolant. Models with 6-cylinder engines Removal 7 Drain the cooling system as described in Chapter 1. 8 Remove the camshaft timing belt front cover, as described in Chapter 2C. Note that this entails the removal of the auxiliary drivebelt (see Chapter 1) and the coolant pump pulley. Thermostat testing 13 A rough test of the thermostat may be made by suspending it on the end of a piece of string in a saucepan full of water. Bring the water to the boil and check that the 4.11 Unscrew the bolts, then remove the cover and integral thermostat 3510 Vauxhall/Opel Omega 4.12 Fit a new sealing ring to the thermostat cover 3 3•6 Cooling, heating and ventilation systems disconnect the radiator vent hose. 4 Unclip the expansion tank from the front suspension turret. 5 Loosen the clips and disconnect the coolant supply and return hoses. 6 Withdraw the expansion tank from the engine compartment. Refitting 7 Refitting is a reversal of the removal procedure. On completion, refill the cooling system with reference to Chapter 1 . 5.9 Progressively slacken and remove the water pump retaining bolts 9 Progressively slacken and remove the water pump retaining bolts (see illustration). Note that the bolts are of different lengths; make a note of the fitted position of each bolt to ensure correct refitting. 10 Lift the coolant pump away from the engine and recover the seal (see illustrations). Refitting 11 Refit the coolant pump by following the removal procedure in reverse, noting these points:. a) Use a new coolant pump sealing ring.. b) Coat the new sealing ring and the pump mating surface with silicon grease before fitting. c) Tighten the coolant pump securing bolts to the specified torque. d) Refit the timing belt cover, coolant pump pulley and auxiliary drive belt, according to the information given in Chapter 2C and Chapter 1 (as applicable). e) On completion, refill the cooling system with the specified quantity of correctlymixed coolant. 6 Expansion tank removal and refitting 2 7 Temperature gauge sender unit removal and refitting 2 Removal Warning: If the engine is hot, allow it to cool before attempting to remove the unit. 1 On all models, the temperature gauge sender unit is located on the rear of the cylinder block between the cylinder heads. Note that the gauge sender has a single electrical terminal; do not confuse it with the engine management coolant temperature sensor which has a two-way electrical connector. To gain access, refer to Chapter 4A and remove the upper section of the inlet manifold. 2 Remove the filler cap from the radiator or expansion tank to release any remaining pressure, then refit the cap - the vacuum will help to reduce the loss of coolant. 3 Disconnect the wiring from the terminal on the sender unit. 4 Unscrew and remove the sender unit, recovering the sealing ring (where fitted). Temporarily plug the aperture with a suitable bung. Note: Be prepared for an amount of coolant loss - position a container under the thermostat housing and pad the area with absorbent rags . Refitting Removal 1 Drain the cooling system as described in Chapter 1. 2 Remove the filler cap. 3 Where applicable, loosen the clip and 5 Refitting is a reversal of the removal procedure. Use a new sealing ring and tighten the sender to the specified torque. On completion, top up the cooling system as detailed in Weekly checks. 8 Heater/ventilation system components removal and refitting 3 Note: For models equipped with Electronic Climate Control, refer to the information given in Section 13. Heater control panel switches Removal 1 Disconnect the battery negative cable and position it away from the terminal. 2 The number and types of switches fitted will vary with model specification, but the removal method for each switch is identical. 3 Obtain two small flat bladed screwdrivers. Pad the ends of the blades with insulating tape. 4 Insert the screwdrivers into the recesses at either side of the switch to be removed. Carefully depress the locking tabs and lever the switch button away from the switch body. 5 Squeeze the locking tabs at either side of the switch body together, then slide the switch body from the heater control panel. Refitting 6 Refitting is a reversal of the removal procedure. Heater control panel Removal 7 Remove the switches from the heater control panel as described in the previous sub-Section. 8 Pull the rotary knobs from the four heat and air distribution control shafts. 9 Remove radio unit from the facia as described in Chapter 12. 10 Unclip and remove the storage compartment adjacent to the radio aperture. 11 Slacken and remove the five heater control panel securing screws; one at the rear of the radio aperture, one at the rear of the storage compartment aperture, and one below each heat/air distribution control shaft. 12 Withdraw the heater control panel from heater control unit. 13 At the rear of the control panel, slide the locking bars to one side and unplug the electrical connectors from the panel. Also unplug the wiring for the panel illumination bulbs and the cigarette lighter. Refitting 14 Refitting is a reversal of the removal procedure. Heater control unit 5.10a Lift the coolant pump away from the engine . . . 5.10b . . . and recover the seal 3510 Vauxhall/Opel Omega 15 Remove the heater control panel as described in the previous sub-Section. 16 Remove the screws and detach the heater control unit from the facia. 17 Prise open the retaining brackets and release both air temperature control cables from the control shafts. Cooling, heating and ventilation systems 3•7 18 Unplug the wiring connector from the rear of the fan control switch. 19 Disconnect the vacuum control hose manifold from the rear of the control panel. 20 Remove the control panel from the vehicle. 38 Working inside the car, unscrew and remove the last distribution unit securing bolt. 39 Pull the unit up and away from the facia, the lift it over the facia wiring harness and remove it from the vehicle. Refitting 40 Refitting is a reversal of the removal procedure, noting the following points:. a) Use new O-ring seals when reconnecting the heater matrix coolant pipes. b) Use new O-ring seals when reconnecting the air conditioning refrigerant pipes to the bulkhead. c) Observe the correct tightening torques when reconnecting the steering column bracing strut (see Chapter 10). d) On model with air conditioning, have the refrigerant circuit evacuated and recharged by an air conditioning specialist or a Vauxhall dealer. e) Ensure that all vacuum and electrical connections are securely re-made f) On completion, refill the cooling system as described in Chapter 1. 21 Refitting is a reversal of the removal procedure. Air distribution unit Note: On models with air conditioning, this procedure involves having the refrigerant circuit discharged by a Vauxhall dealer or an air conditioning specialist. Removal 22 Drain the coolant as described in Chapter 1. 23 Remove the facia as described in Chapter 11. 24 On models with air conditioning, the refrigerant circuit must be now be discharged by an air conditioning specialist or a Vauxhall dealer, to allow the air conditioning lines to be disconnected from the engine compartment bulkhead. Refer to the precautions given in Section 11 before proceeding. 25 Unclip and remove the duct for the face level air vent on the drivers side of the vehicle. 26 With reference to Chapter 10, unbolt and remove the steering column bracing strut, from the steering column and the floorpan. 27 Undo the bolt and release the earth cable from the bulkhead. 28 Unplug the wiring connector from the blower motor resistor pack, at the connector. 29 Place a suitable container beneath the point where the heater matrix coolant pipes enter the air distribution unit. 30 Unscrew the bolt to release the pipe retaining plate, then disconnect the coolant pipes from the heater matrix, at the right hand side of the air distribution unit. Allow the escaping coolant to drain into the container. Press the coolant pipes back towards the engine compartment, clear of the air distribution unit. 31 On models with air conditioning, disconnect the black vacuum hose from the coolant cut-off valve. 32 Unplug the wiring connector from the recirculation valve solenoid. 33 On models without electronic climate control, disconnect the yellow vacuum hose from the air distribution unit. 34 Undo the securing screws and detach the rear passenger compartment footwell ducts from the distribution unit. 35 Disconnect the blue vacuum hose from the recirculation valve vacuum unit. 36 On models with automatic transmission, release the cable ties and separate the selector cable from the recirculation valve solenoid. 37 Working in the engine compartment, slacken and withdraw the two distribution unit securing bolts, located near the upper edge of the bulkhead. Refitting Heater matrix 41 See Section 9. Blower motor and fan 42 See Section 10. Heater control cable driver’s side Removal 43 Release the facia from the bulkhead, with reference to Chapter 11. Pull it away from the bulkhead just far enough to gain access to the rear of the air distribution unit. 44 Prise open the retaining clip and then disconnect the cable inner from the operating lever on the air distributor unit. 45 Remove the heater control panel as described earlier in this Section. 46 Prise open the retaining clip and then disconnect the cable inner from the quadrant at the end of the control shaft. 47 Remove the cable from the vehicle. Refitting 48 Refitting is a reversal of the removal procedure. Set the operating lever on the air distributor unit in the vertical position before reconnecting the control cable inner. Heater control cable passenger side 49 Proceed as described for the driver’s side control cable, in the previous sub-Section, noting that the air duct for the passenger footwell vent must be removed to gain access to the cable. Recirculation air valve solenoid Removal 50 Disconnect the battery negative cable and position it away from the terminal. 3510 Vauxhall/Opel Omega 51 On right hand drive models, remove the glove compartment from the facia, as described in Chapter 11, then unclip and remove the air duct for the passenger footwell vent. 52 On left hand drive models, remove the lower trim panel from the drivers side of the facia, then unclip and remove the air duct for the drivers footwell vent. 53 The solenoid is mounted on the left hand side of the air distributor unit. Note the connection order of each of the vacuum hoses, then disconnect them from the solenoid valve ports. 54 Unplug the wiring connector from the solenoid valve. 55 Slacken and withdraw the securing screw then remove the solenoid valve from the vehicle. Refitting 56 Refitting is a reversal of the removal procedure. Ensure that the valve sits squarely in its guide slots, and that the vacuum hoses are correctly reconnected according to the notes made during removal. Recirculation air valve vacuum unit Removal 57 Remove the glove compartment from the facia, as described in Chapter 11. 58 Release the cable ties, then depress the locking tabs and disengage the wiring harness support from the facia. Unclip and remove the air ducting. 59 The recirculation air valve vacuum unit is located on the left hand side of the blower motor housing, and is distinguished by the blue vacuum hose leading to it. 60 Disconnect the vacuum hose from the side of the vacuum unit. 61 Lever the unit from its mounting boss. Disconnect the actuator arm from the lever at the base of the vacuum unit, then remove the vacuum unit from the vehicle. Refitting 62 Refitting is a reversal of the removal procedure. Defroster valve vacuum unit 63 Proceed as described for the recirculation valve vacuum unit, in the previous subSection. The defroster valve vacuum unit is located on the right hand side of the air distributor unit and is distinguished by the brown vacuum hose leading to it. Footwell valve vacuum unit 64 Proceed as described for the recirculation valve vacuum unit, in the previous subSection. The footwell valve vacuum unit is located on the right hand side of the air distributor unit and is distinguished by the green vacuum hose leading to it. 3 3•8 Cooling, heating and ventilation systems Vacuum control circuit General information 65 The heating and ventilation system is controlled by a series of valves which direct air through the required air ducts, according to the position of the control knobs on the heater control panel. The valves are actuated by vacuum supplied engine inlet manifold. The following diagram is provided to show the order of vacuum hose and vacuum unit connection (see illustration). 9 Heater matrix removal and refitting 4 Removal 1 Disconnect the battery negative cable and position it away from the terminal. 2 Drain the coolant as described in Chapter 1. 3 Refer to Chapter 11 and remove the facia. 4 With reference to Chapter 10, unbolt the lower end of the steering column bracing strut and pivot it upwards away from the floorpan. 5 Remove the securing screw and unclip the air duct for the drivers footwell vent from the side of the air distributor unit. 6 Detach the drivers side control cable from the air distributor unit, as described in the previous Section. 7 Place a suitable container beneath the point where the heater matrix coolant pipes enter the air distribution unit. 8 Unscrew the bolt to release the pipe retaining plate, then disconnect the coolant pipes from the heater matrix, at the right hand side of the air distribution unit, and recover the O-ring seals. Allow the escaping coolant to drain into the container. Press the coolant pipes back towards the engine compartment, clear of the air distribution unit. 9 Slacken and remove the securing screws then withdraw the heater matrix from the side of the air distribution unit, recover the rubber seal (see illustration). If a new heater matrix is to be fitted, extract the captive nut (for the coolant pipe retaining plate) from the plastic casing of the old matrix and transfer it to the new one. 8.65 Heating/ventilation system vacuum control circuit 1 2 3 4 5 6 7 8 Vacuum reservoir Blue vacuum hose Vacuum unit, recirculating air valve Vacuum unit, defroster valve Brown vacuum hose Vacuum unit, footwell valve Green vacuum hose Connector, vacuum hoses 9 10 11 12 13 14 15 16 Refitting 10 Refitting is a reversal of the removal procedure, noting the following points:. a) Use new O-ring seals when reconnecting the heater matrix coolant pipes. b) Observe the correct tightening torques when reconnecting the steering column bracing strut (see Chapter 10). c) On completion, refill the cooling system as described in Chapter 1. 10 Blower motor and series resistor removal and refitting 3 Heater controls Recirculating air switch Solenoid valve wiring, recirculating air valve Blue vacuum hose Solenoid valve, recirculating air valve Yellow vacuum hose Bulkhead Vacuum supply hose 4 Disconnect the vacuum hose from the side of the air recirculation valve vacuum unit then remove the unit from its mounting bracket (see Section 8). 5 Unplug the wiring harness leading to the blower motor series resistor. 6 Slacken and remove the securing screws, then withdraw the blower motor and fan assembly from its housing (see illustrations). Refitting 7 Refitting is a reversal of the removal procedure. Blower motor Removal 9.9 Heater matrix securing screw (A) and coolant pipe retaining plate bolt (B) 1 Disconnect the battery negative cable and position it away from the terminal. 2 Remove the glove compartment from the facia as described in Chapter 11. 3 Release the cable ties, then depress the locking tabs and disengage the wiring harness support from the facia. Unclip and remove the air ducting. 3510 Vauxhall/Opel Omega 10.6a Slacken and remove the securing screws . . . Cooling, heating and ventilation systems 3•9 form a highly poisonous gas. It is therefore extremely dangerous to disconnect any part of the air conditioning system without specialised knowledge and equipment. 7 Uncontrolled discharging of the refrigerant can also be damaging to the environment, as certain refrigerants contain CFCs. 8 Do not operate the air conditioning system if it is known to be short of refrigerant, as this will damage the compressor. Series resistor Removal 8 Proceed as described in paragraphs 1 to 3 inclusive in the previous sub-Section. 9 Unplug the wiring harness from the blower motor series resistor at the connector (see illustration). 10 Depress the retaining tabs and withdraw the resistor from the fan/motor housing (see illustration). Refitting 11 Refitting is a reversal of removal. 10.6b . . . then withdraw the blower motor and fan assembly from its housing 11 Air conditioning system description and precautions temperature in the passenger compartment. On models with Electronic Climate control, the cabin temperature is regulated automatically by a system of air valves controlled by servo motors. 4 The heating side of the system works in the same way as on models without air conditioning (see Section 8). 5 The operation of the system is controlled by an electronic control unit, which controls the electric cooling fan, the compressor, and the facia-mounted warning light. Any problems with the system should be referred to a Vauxhall dealer. General information 1 An air conditioning system is available on certain models. When activated, the air conditioning system allows air entering the passenger to be cooled giving greater control over the temperature inside the car and leading to increased comfort. The cooled air is also dehumidified, enabling faster windscreen demisting. 2 The cooling side of the system works in the same way as a domestic refrigerator. Refrigerant gas, contained in a sealed network of alloy pipes, is drawn into a belt-driven compressor, and is forced through a condenser mounted on the front of the radiator. On entering the condenser, the refrigerant changes state from gas to liquid and releases heat, which is absorbed by the air flowing into the engine compartment through the condenser. The liquid refrigerant passes through an expansion valve to an evaporator, where it changes from liquid under high pressure to gas under low pressure. This change in state is accompanied by a drop in temperature, which cools the evaporator. Air passing through the evaporator is cooled before flowing into the air distribution unit. The refrigerant then returns to the compressor, and the cycle begins again. 3 Cool air passes to the air distribution unit, where it is mixed with hot air blown through the heater matrix, to achieve the desired Precautions 6 When an air conditioning system is fitted, it is necessary to observe special precautions whenever dealing with any part of the system, or its associated components. If for any reason the system must be disconnected, you must entrust this task to a Vauxhall dealer or an air conditioning specialist. Similarly, the system can only be evacuated and recharged by a dealer or air conditioning specialist. Warning: The air conditioning system contains a pressurised liquid refrigerant. If the system is discharged in an uncontrolled manner without the aid of specialist equipment, the refrigerant will boil as soon as it is exposed to the atmosphere, causing severe frostbite if it comes into contact with unprotected skin. In addition, certain refrigerants, in the presence of a naked flame (including a lit cigarette), will burn to 12 Air conditioning system components removal and refitting 3 Warning: Do not attempt to discharge the refrigerant circuit yourself - refer to the precautions given in Section 11. Have the air conditioning system discharged by a qualified engineer. On completion, have the refrigerant engineer fit new O-rings to the line connections and evacuate and re-charge the system. Auxiliary coolant pump Removal 1 Drain the coolant as described in Chapter 1. 2 Remove the battery as described in Chapter 5A. 3 Remove the screws and lift the upper cover from the top of the radiator. 4 Unplug the wiring from the auxiliary coolant pump at the connector. 5 Release the securing clips and detach the auxiliary coolant pump from the radiator. Refitting 6 Refitting is a reversal of removal. On completion, top up the cooling system as described in Weekly checks. Compressor Removal Models with 4-cylinder engines 7 Have the air conditioning system discharged by a qualified engineer. 8 Remove the battery as described in Chapter 5A. 9 Remove the auxiliary drivebelt as described in Chapter 1. 10 Unbolt the refrigerant lines from the compressor. 11 Unplug the wiring connector from the clutch unit at the underside of the compressor. 12 Unscrew the three securing bolts from the front of the compressor. 13 Unscrew the three securing bolts from the rear of the compressor, then remove the compressor from its mounting bracket. Refitting Models with 4-cylinder engines 10.9 Unplug the wiring harness from the blower motor series resistor at the connector 10.10 Withdraw the resistor from the fan/motor housing 3510 Vauxhall/Opel Omega 14 Refitting is a reversal of the removal procedure; ensure that all fixings are tightened to the specified torque, where given. On 3 3•10 Cooling, heating and ventilation systems completion, have the refrigerant engineer fit new O-rings to the line connections and evacuate and re-charge the refrigerant circuit. Evaporator Removal Models with 6-cylinder engines 34 Remove the expansion valve as described in previous sub-Section, then withdraw the evaporator from the air distributor unit. 15 Have the air conditioning system discharged by a qualified engineer. 16 Remove the battery as described in Chapter 5A. 17 Remove the auxiliary drivebelt as described in Chapter 1. 18 Uncouple the low pressure refrigerant pipe at the service union. Work along the length of the pipe that remains connected to the compressor and release it from any retaining brackets. 19 Uncouple the high pressure refrigerant pipe at the pulsation damper unit. Work along the length of the pipe that remains connected to the compressor and release it from any retaining brackets. 20 Unplug the wiring connector from the clutch unit at the underside of the compressor. 21 Unscrew the three securing bolts from the front of the compressor. 22 Unscrew the two securing bolts from the rear of the compressor. 23 Rotate the compressor so that the fluid filler bolt faces towards the engine sump, then remove the compressor from its mounting bracket. Removal Refitting 35 Refitting is a reversal of removal. Condenser Removal Models with 4 cylinder engines 36 Have the air conditioning system discharged by a qualified engineer. 37 Disconnect the battery negative cable and position it away from the terminal. 38 Remove the radiator as described in Section 2. 39 Slacken and separate the unions, then disconnect the refrigerant lines from the condenser and tape over or plug them. 40 Carefully lift the condenser from its rubber guide and withdraw it from the vehicle. Refitting 41 Refitting is a reversal of removal. Have a refrigerant engineer fit new O-rings to the line connections and then evacuate and re-charge the refrigerant circuit. On completion, refill the cooling system with reference to Chapter 1. Refitting Models with 6-cylinder engines Removal Models with 6 cylinder engines 24 Refitting is a reversal of the removal procedure; ensure that all fixings are tightened to the specified torque, where given. On completion, have the refrigerant engineer fill the compressor with lubricant, fit new O-rings to the line connections and then evacuate and re-charge the refrigerant circuit. 42 Have the air conditioning system discharged by a qualified engineer. 43 Disconnect the battery negative cable and position it away from the terminal. 44 Remove the radiator as described in Section 2. 45 Slacken and separate the unions, then disconnect the refrigerant lines from the condenser and tape over or plug them. 46 Carefully lift the condenser from its rubber guide and tilt it backwards towards the engine. 47 Slacken and separate the unions, then disconnect the refrigerant lines from the receiver/ dryer unit and tape over or plug them. 48 Undo the screws and detach the receiver/dryer unit mounting bracket from the condenser. 49 Carefully lift the condenser from its rubber guide and withdraw it from the vehicle, together with the receiver/dryer unit. Expansion valve 25 Have the air conditioning system discharged by a qualified engineer. 26 Disconnect the battery negative cable and position it away from the terminal. 27 Refer to Chapter 11 and remove the glove compartment. 28 Refer to Section 10 and remove the blower motor. 29 Disconnect the refrigerant lines at the engine compartment bulkhead. 30 Unbolt the solenoid valves from the evaporator housing and position them to one side. 31 Remove the six securing screws and lift the evaporator cover from the air distributor unit. 32 Unbolt the retainer plate, disconnect the refrigerant lines, then unbolt the expansion valve from the evaporator. Refitting 33 Refitting is a reversal of removal. Ensure that all fixings are tightened to the specified torque, where given. On completion, have the refrigerant engineer fit new O-rings to the line connections and then evacuate and re-charge the refrigerant circuit. 52 Disconnect the battery negative cable and position it away from the terminal. 53 Refer to Chapter 11 and remove the radiator grille. 54 Detach the filler neck from the top of the windscreen washer fluid reservoir. On models with 6-cylinder engines, unbolt and remove the crossmember from the front of the engine compartment. 55 Punch out the pre-stressed holes in the cooling fan casing to gain access to the refrigerant line unions, at the top of the receiver/dryer unit. 56 Slacken and separate the unions, then disconnect the refrigerant lines from the receiver/ dryer unit and tape over or plug them. 57 Undo the screws and detach the receiver/dryer unit mounting bracket from the front of the vehicle. Remove the unit from the engine compartment, together with its mounting bracket. Refitting 58 Refitting is a reversal of removal. On completion, have a refrigerant engineer fit new O-rings to the line connections and then evacuate and re-charge the refrigerant circuit. Tri-switch Removal 59 The tri-switch is located beneath receiver/dryer unit at the front left hand corner of the engine compartment. Have the air conditioning system discharged by a qualified engineer. 60 Disconnect the battery negative cable and position it away from the terminal. 61 Unplug the wiring from the tri-switch at the multi-way connector. 62 Counterhold the refrigerant line union and unscrew the tri-switch. Refitting 63 Refitting is a reversal of removal. On completion, have a refrigerant engineer fit new O-rings to the line connections and then evacuate and re-charge the refrigerant circuit. Cooling fan thermo-switches Main radiator fan 50 Refitting is a reversal of removal. Have a refrigerant engineer fit new O-rings to the line connections and then evacuate and re-charge the refrigerant circuit. On completion, refill the cooling system with reference to Chapter 1. 64 The main radiator fan thermo-switch is located at the lower edge of the radiator. 65 Drain the cooling system as described in Chapter 1. 66 Disconnect the battery negative cable and position it away from the terminal. 67 Unplug the wiring from the switch at the multi-way connector. 68 Unscrew the switch from the radiator. 69 Refitting is a reversal of removal, but use a new switch sealing ring. On completion refill the cooling system as described in Chapter 1. Receiver/dryer Auxiliary fan Refitting Models with 6 cylinder engines Removal 51 Have the air conditioning discharged by a qualified engineer. 3510 Vauxhall/Opel Omega system 70 The auxiliary radiator fan thermo-switch is located at the left hand side of the radiator. 71 Drain the cooling system as described in Chapter 1. Cooling, heating and ventilation systems 3•11 13.4 Slacken and remove the securing screws from the lower edge of the ECC panel 72 Disconnect the battery negative cable and position it away from the terminal. 73 Unplug the wiring from the switch at the multi-way connector. 74 Unscrew the switch from the radiator. 75 Refitting is a reversal of removal, but use a new switch sealing ring. On completion refill the cooling system as described in Chapter 1. 13 Electronic Climate Control (ECC) components removal and refitting 3 ECC control panel and switches Removal 1 Disconnect the battery negative cable and position it away from the terminal. 2 Remove ashtray from the facia as described in Chapter 11. 3 Remove radio unit from the facia as described in Chapter 12, then remove the radio mounting frame. 4 Slacken and remove the securing screws from the lower edge of the control panel (see illustration). 5 Reach through the radio aperture and pull down on the aluminium locking bar at the rear of the upper edge of the control panel (see illustrations). 6 Remove the panel from the facia. At the rear of the control panel, slide the locking bars to one side and unplug the electrical connectors from the panel. Also unplug the wiring for the control panel and ashtray illumination bulbs (see illustrations). 7 If required, the ECC switch controls can be detached from the control panel by removing the relevant securing screws. 13.5a Reach through the radio aperture . . . Defroster air valve servo motor Removal 9 Disconnect the battery negative cable and position it away from the terminal. Remove the lower trim panel from the drivers side of the facia, then unclip and remove the air duct for the drivers footwell vent. 10 The servo motor is mounted on the right hand side of the air distributor unit (see illustration). 11 Unplug the wiring harness from the servo motor at the multiway connector. 12 Undo the securing screws and withdraw the servo motor from the air distributor unit. 13 Disengage the motor spindle arm from the actuator rod. Refitting 14 Refitting is a reversal of removal. On completion, synchronise the air valve servo 13.5b . . . and pull down on the aluminium locking bar at the rear of the upper edge of the control panel (shown with panel removed for clarity) motors as follows: turn the ignition switch to the On position, then depress and hold the Auto and Off keys on the ECC control panel for more than 5 seconds. Footwell air valve servo motor Removal 15 Refer to the previous sub-Section and remove the defroster air valve servo motor. 16 The servo motor is mounted on the right hand side of the air distributor unit, in front of the defroster air valve servo motor (see illustration). 17 Unplug the wiring harness from the servo motor at the multiway connector. 18 Undo the securing screws and withdraw the servo motor from the air distributor unit. 3 13.6a Unplug the wiring harness connectors . . . 13.6b . . . and remove the ECC panel from the facia 13.10 Location of the ECC defroster air valve servo 13.16 Location of the ECC footwell air valve servo Refitting 8 Refitting is a reversal of removal, noting the following points:. a) Ensure that locking bar at the rear upper edge of the control panel is correctly engaged. b) On completion, synchronise the air valve servo motors as follows: Switch the ignition to the On position, then depress and hold the Auto and Off keys on the ECC control panel for more than 5 seconds. 3510 Vauxhall/Opel Omega 3•12 Cooling, heating and ventilation systems 13.32 Unclip the cover panel to expose the right hand vent servo motor Refitting 19 Turn the servo motor spindle gear fully clockwise to the end of its stop. Similarly, turn the spindle gear air distributor housing fully clockwise to the end of its stop. 20 Refit the motor and tighten its securing screws. Reconnect the wiring harness. 21 Refit the defroster air valve servo motor as described in the previous sub-Section. Refit all components removed for access. 22 On completion, synchronise the air valve servo motors as follows: turn the ignition switch to the On position, then depress and hold the Auto and Off keys on the ECC control panel for more than 5 seconds. Centre vent servo motor Removal 23 Disconnect the battery negative cable and position it away from the terminal. 24 Remove the lower trim panel from the drivers side of the facia, then unclip and remove the air duct for the drivers footwell vent. 25 The servo motor is mounted on the right hand side of the air distributor unit, above the defroster air valve servo motor. 26 Unplug the wiring harness from the servo motor at the multiway connector. 27 Undo the securing screws and withdraw the servo motor from the air distributor unit. 28 Disengage the motor spindle arm from the actuator rod. Refitting 29 Refitting is a reversal of removal. On completion, synchronise the air valve servo motors as follows: turn the ignition switch to the On position, then depress and hold the Auto and Off keys on the ECC control panel for more than 5 seconds. Right hand vent temperature sensor Right hand vent servo motor Removal Removal 44 Remove the footwell air valve servo motor as described earlier in this Section. 45 Unplug the wiring from the sensor at the connector. 46 Carefully prise the sensor body away from its mounting clip and withdraw the probe from the air ducting (see illustration). 30 Disconnect the battery negative cable and position it away from the terminal. 31 Remove the lower trim panel from the drivers side of the facia, then unclip and remove the air duct for the drivers footwell vent. 32 Unclip the cover panel to expose the servo motor (see illustration). 33 Unplug the wiring harness from the servo motor at the multiway connector. 34 Undo the securing screws and withdraw the servo motor from the air distributor unit. 35 Disengage the motor spindle arm from the actuator rod and actuator lever. Refitting 36 Refitting is a reversal of removal. On completion, synchronise the air valve servo motors as follows: turn the ignition switch to the On position, then depress and hold the Auto and Off keys on the ECC control panel for more than 5 seconds. Left hand vent servo motor Removal 37 Disconnect the battery negative cable and position it away from the terminal. Remove the glove compartment from the facia, as described in Chapter 11. 38 Release the cable ties, then depress the locking tabs and disengage the wiring harness support from the facia. Unclip and remove the air ducting. 39 Unclip the cover panel to expose the servo motor. 40 Unplug the wiring harness from the servo motor at the multiway connector. 41 Undo the securing screws and withdraw the servo motor from the air distributor unit. 42 Disengage the motor spindle arm from the actuator rod and actuator lever. Refitting 47 Refitting is a reversal of removal. On completion, refit the footwell air valve servo motor, then synchronise the air valve servo motors as follows: turn the ignition switch to the On position, then depress and hold the Auto and Off keys on the ECC control panel for more than 5 seconds. Left hand vent temperature sensor Removal 48 Disconnect the battery negative cable and position it away from the terminal. Remove the glove compartment from the facia, as described in Chapter 11. 49 Release the cable ties, then depress the locking tabs and disengage the wiring harness support from the facia. Unclip and remove the air ducting. 50 Note the direction that the wiring connector is facing, then pull the sensor to release it from the air distributor unit, then rotate it clockwise through half a turn and unplug the wiring connector. 51 Tilt the sensor to the left and withdraw it from its aperture. Refitting 52 Refitting is a reversal of removal. Ensure that when the sensor is refitted, the wiring connector faces the right hand side of the vehicle, as noted during removal. Blower motor regulator Refitting Removal 43 Refitting is a reversal of removal. On completion, synchronise the air valve servo motors as follows: turn the ignition switch to the On position, then depress and hold the Auto and Off keys on the ECC control panel for more than 5 seconds. 53 Disconnect the battery negative cable and position it away from the terminal. Remove the glove compartment from the facia, as described in Chapter 11. 54 Depress the retaining lugs and withdraw the regulator from the fan housing. Unplug the wiring from the regulator at the connector. Refitting 55 Refitting is a reversal of removal. Sun sensor Removal 56 Carefully lever the sensor from the facia using blunt soft bladed instrument (see illustration). 57 Secure a cable tie around the wiring harness to prevent it from falling back into the facia, then disconnect it from the sensor. 13.46 Location of the ECC right hand vent temperature sensor 13.56 Carefully lever the sun sensor from the upper surface of the facia 3510 Vauxhall/Opel Omega Refitting 58 Refitting is a reversal of removal. 4A•1 Chapter 4 Part A: Fuel and exhaust systems Contents Accelerator cable - removal and refitting . . . . . . . . . . . . . . . . . . . . . 3 Accelerator pedal - removal and refitting . . . . . . . . . . . . . . . . . . . . . 4 Air cleaner assembly and intake ducts - removal and refitting . . . . . 2 Air cleaner filter element renewal . . . . . . . . . . . . . . . . . .See Chapter 1 Exhaust manifold - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 16 Exhaust system - general information, removal and refitting . . . . . . 18 Exhaust system check . . . . . . . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Fuel filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Fuel gauge sender unit - removal and refitting . . . . . . . . . . . . . . . . . 9 Fuel injection system - depressurisation . . . . . . . . . . . . . . . . . . . . . . 7 Fuel injection system - testing and adjustment . . . . . . . . . . . . . . . . . 12 Fuel injection system components (2.0 litre engine) - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Fuel injection system components (2.5 and 3.0 litre engines) - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Fuel injection systems - general information . . . . . . . . . . . . . . . . . . . 6 Fuel pump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Fuel tank - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 General information and precautions . . . . . . . . . . . . . . . . . . . . . . . . 1 Inlet manifold - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 15 Multi-ram air intake system - information and component removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Throttle housing - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 11 Unleaded petrol - general information and usage . . . . . . . . . . . . . . . 5 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 4A 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional Specifications System type 2.0 litre SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 litre DOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . *See Section 6 for further information Bosch Motronic M1.5.4* Simtec 56.1 or 56.5* Bosch Motronic M2.8.1 or M2.8.3* Fuel system data Fuel pump type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel pump regulated pressure (approximate) . . . . . . . . . . . . . . . . . . . . . Specified idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Idle mixture CO content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electric, immersed in tank 3.0 bar Not adjustable - controlled by ECU Not adjustable - controlled by ECU Recommended fuel Minimum octane rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 RON* unleaded (UK unleaded premium). Leaded fuel must not be used *91 RON unleaded fuel can be used but a slight power loss maybe noticeable. 3510 Vauxhall/Opel Omega 5 4A•2 Fuel and exhaust systems Torque wrench settings Auxiliary drivebelt tensioner mounting bolts - 2.5 and 3.0 litre engines . Braking system vacuum hose union nut . . . . . . . . . . . . . . . . . . . . . . . . Camshaft sensor bolt: 2.0 litre DOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft sensor bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EGR pipe union nuts - 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . Exhaust manifold heatshield bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust manifold nuts: 2.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust system fasteners: Front pipe to manifold bolts: 2.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front pipe to mounting bracket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . Front pipe to intermediate pipe bolts . . . . . . . . . . . . . . . . . . . . . . . . . Intermediate pipe to tailpipe clamp . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel hose union nuts/bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel pressure regulator clamp screw . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel rail bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel tank retaining strap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inlet manifold nuts and bolts: 2.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engines: Flange to cylinder head bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lower section: Retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel pipe adaptor mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . Upper section retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Knock sensor bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil cooler pipe union nuts and bolts - 2.5 and 3.0 litre engines . . . . . . . Spark plug heatshields - 2.0 litre SOHC engine . . . . . . . . . . . . . . . . . . . Throttle housing nuts/bolts: 2.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 General information and precautions 1 The fuel system consists of a fuel tank (which is mounted under the rear of the car, with an electric fuel pump immersed in it), a fuel filter and the fuel feed and return lines. The fuel pump supplies fuel to the fuel rail, which acts as a reservoir for the fuel injectors (one for each cylinder) which inject fuel into the inlet tracts. In addition, there is an Electronic Control Unit (ECU) and various sensors, electrical components and related wiring. 2 Refer to Section 6 for further information on the operation of each fuel injection system, and to Section 18 for information on the exhaust system. Warning: Many of the procedures in this Chapter require the removal of fuel lines and connections, which may result in some fuel spillage. Before carrying out any operation Nm 35 20 Ibf ft 26 15 6 8 8 25 8 4 6 6 18 6 22 20 16 15 25 30 20 18 17 15 18 22 15 13 13 11 8 30 6 22 22 16 20 15 20 8 8 20 30 25 15 6 6 15 22 18 9 8 7 6 on the fuel system, refer to the precautions given in Safety first! at the beginning of this manual, and follow them implicitly. Petrol is a highly-dangerous and volatile liquid, and the precautions necessary when handling it cannot be overstressed. Note: Residual pressure will remain in the fuel lines long after the vehicle was last used. Before disconnecting any fuel line, first depressurise the fuel system as described in Section 7. 2 Air cleaner assembly and intake ducts removal and refitting 2 Removal Note: On 2.5 and 3.0 litre engines, refer to Section 17 for information on the multi-ram air intake system. 1 To remove the air cleaner housing slacken the retaining clip and disconnect the duct from the outlet then unclip the housing from 3510 Vauxhall/Opel Omega its mounting rubbers. Free the housing from the intake duct and remove it from the engine compartment. 2 The various ducts can be disconnected and removed once the retaining clips have been slackened. In some cases it will be necessary to disconnect breather hoses and wiring connectors to allow the duct to be removed; some duct sections are also bolted to a support bracket. Refitting 3 Refitting is the reverse of removal, noting the following. a) Examine the housing mounting rubbers for signs of damage or deterioration and renew if necessary. b) On refitting, remove the mounting rubbers from the body and fit them to the housing pins. Ease installation by lubricating the mounting rubbers with a spray-based silicone lubricant. c) Ensure all ducts are securely joined and retained by the necessary clips and screws. Fuel and exhaust systems 4A•3 3 Accelerator cable removal and refitting 3 Removal 1 Working in the engine compartment, unclip the inner cable retaining clip then slide the clip out of the end fitting and release the cable from the throttle cam (see illustration). 2 Free the accelerator outer cable from its mounting bracket, taking care not to lose the adjusting clip (see illustration). Work back along the length of the cable, free it from any retaining clips or ties, noting its correct routing. On models with automatic transmission it will be necessary to disconnect the wiring from the kickdown switch which is built into the cable. 3 To improve access, remove the windscreen wiper arms and the water deflector panel from the base of the windscreen (see Chapter 12, Sections 15 and 16). 4 From inside the vehicle, release the retaining clips (rotate them through 90º) then remove the undercover panel from the drivers’ side of the facia. Remove the fastener (prise out the centre pin then pull out the fastener outer section) then unclip and remove the heater/ventilation duct to improve access to the accelerator pedal (see illustrations). 5 Reaching up behind the facia, unclip the accelerator inner cable from the top of the accelerator pedal (see illustration). 3.4a Release the retaining clips and remove the undercover panel from the driver’s side of the facia 3.4b Prise out the centre pin then remove the fastener outer section . . . 3.1 Remove the retaining clip and detach the inner cable from the throttle cam . . . 6 Return to the engine compartment then free the cable sealing grommet from the bulkhead and remove the cable and grommet from the vehicle. 7 Examine the cable for signs of wear or damage and renew if necessary. Refitting 8 Feed the cable into position from the engine compartment and seat the outer cable grommet in the bulkhead. 9 From inside the vehicle, clip the inner cable end fitting into position in the pedal end and check to make sure the grommet is correctly located in the bulkhead. Check that the cable is securely retained, then refit the heater/ventilation duct and undercover to the facia. 10 From within the engine compartment, ensure the outer cable is correctly seated in the bulkhead, then work along the cable, securing it in position with the retaining clips and ties, and ensuring that the cable is correctly routed. On models with automatic transmission, reconnect the kickdown switch wiring connector making sure the wiring is correctly routed. 11 Refit the water deflector panel and install both wiper arms (see Chapter 12). 12 Connect the inner cable to the throttle cam and secure it in position with the retaining clip. Clip the outer cable into its mounting bracket and adjust the cable as described below. 3.4c . . . and unclip the heater/ventilation duct 3510 Vauxhall/Opel Omega 3.2 . . . then free the outer cable from the mounting bracket Adjustment 13 Working in the engine compartment, slide off the adjustment clip from accelerator outer cable. 14 With the clip removed, ensure that the throttle cam is fully against its stop. Gently pull the cable out of its grommet until all free play is removed from the inner cable. 15 With the cable held in this position, refit the spring clip to the last exposed outer cable groove in front of the rubber grommet. When the clip is refitted and the outer cable is released, there should be only a small amount of free play in the inner cable. 16 Have an assistant depress the accelerator pedal, and check that the throttle cam opens fully and returns smoothly to its stop. 4 Accelerator pedal removal and refitting 3 Removal 1 From inside the vehicle, release the retaining clips (rotate them through 90º) then remove the undercover panel from the drivers’ side of the facia. Remove the fastener (prise out the centre pin then pull out the fastener outer section) then unclip and remove the heater/ventilation duct to improve access to the accelerator pedal (see illustrations 3.4a to 3.4c). 3.5 Unhook the accelerator cable (arrowed) from the upper end of the pedal 4A 4A•4 Fuel and exhaust systems 4.3 Undo the retaining nuts (arrowed) and remove the accelerator pedal from the vehicle 2 Reaching up behind the facia, unclip the accelerator inner cable end fitting from the top of the accelerator pedal (see illustration 3.5). 3 Unscrew the retaining nuts and remove the pedal assembly from the bulkhead (see illustration). 4 Inspect the pedal assembly for signs of wear, paying particular attention to the pedal bushes, and renew as necessary. To dismantle the assembly, unhook the return spring then slide off the retaining clip and separate the pedal, mounting bracket, return spring and pivot bushes. Refitting 5 If the assembly has been dismantled, apply a smear of multi-purpose grease to the pedal pivot shaft and bushes. Fit the bushes and return spring to the mounting bracket and insert the pedal, making sure it passes through the return spring bore. Secure the pedal in position with the retaining clip and hook the return spring back behind the pedal. 6 Refit the pedal assembly and securely tighten its retaining nuts. 7 Clip the accelerator cable end fitting into the pedal then refit the heater/ventilation duct and undercover to the facia. 8 On completion, adjust the accelerator cable as described in Section 3. 5 Unleaded petrol general information and usage Note: The information given in this Chapter is correct at the time of writing. If updated information is thought to be required, check with a Vauxhall dealer. If travelling abroad, consult one of the motoring organisations (or a similar authority) for advice on the fuel available. 1 The fuel recommended by Vauxhall is given in the Specifications Section of this Chapter, followed by the equivalent petrol currently on sale in the UK. 2 All petrol models are designed to run on fuel with a minimum octane rating of 95 (RON). Lower octane fuel, down to minimum of rating 91 (RON), can be safely used since the engine management system automatically adjusts the ignition timing to suit (using the information supplied by the knock sensor). However, a slight power loss is likely if fuel with a octane rating of less than 95 (RON) is used. Vauxhall state that if 91 octane fuel is to be used, as a precautionary measure, it is wise to avoid placing the engine under severe loads for any length of time (eg. towing or full throttle driving). 3 All UK models have a catalytic converter, and so must be run on unleaded fuel only. Under no circumstances should leaded fuel (UK 4-star) be used, as this may damage the converter. 4 Super unleaded petrol (98 octane) can also be used in all models if wished, though there is no advantage in doing so. 6 Fuel injection systems general information 2.0 litre SOHC engine models Bosch Motronic M1.5.4 system 1 All 2.0 litre SOHC engine models are equipped with a Bosch Motronic engine management (fuel injection/ignition) system (see illustration). On UK models the system incorporates a closed-loop catalytic converter, an evaporative emission control system and an exhaust gas recirculation (EGR) system and complies with the latest emission control standards. The fuel injection side of the system operates as follows; refer to Chapter 5B for information on the ignition system. 2 The fuel pump, immersed in the fuel tank, pumps fuel from the fuel tank to the fuel rail, via a filter mounted underneath the rear of the vehicle. Fuel supply pressure is controlled by the pressure regulator which allows excess fuel to be returned to the tank. 3 The electrical control system consists of the ECU, along with the following sensors. a) Throttle potentiometer - informs the ECU of the throttle position, and the rate of throttle opening or closing. b) Coolant temperature sensor - informs the ECU of engine temperature. c) Airflow meter - informs the ECU of the amount of air entering the inlet manifold. d) Intake air temperature sensor - informs the ECU of the temperature of the air entering the manifold. e) Crankshaft sensor - informs the ECU of engine speed and crankshaft position. f) Knock sensor - informs the ECU when pre-ignition (pinking) is occurring. g) Oxygen sensor (UK models) informs the ECU of the oxygen content of the exhaust gases (explained in greater detail in Part B of this Chapter). h) ABS control unit - informs the ECU of the vehicle speed. 3510 Vauxhall/Opel Omega i) Air conditioning system compressor switch (where fitted) - informs ECU when the air conditioning system is switched on. 4 All the above information is analysed by the ECU and, based on this, the ECU determines the appropriate ignition and fuelling requirements for the engine. The ECU controls the fuel injector by varying its pulse width - the length of time the injector is held open - to provide a richer or weaker mixture, as appropriate. The mixture is constantly varied by the ECU, to provide the best setting for cranking, starting (with either a hot or cold engine), warm-up, idle, cruising, and acceleration. 5 The ECU also has full control over the engine idle speed, via the idle speed adjuster which is fitted to the throttle housing. The adjuster controls the opening of an air passage which bypasses the throttle valve. When the throttle valve is closed (accelerator pedal released), the ECU uses the adjuster to vary the amount of air entering the engine and so controls the idle speed. 6 The ECU also controls the exhaust and evaporative emission control systems, which are described in detail in Part B of this Chapter. 7 If there is an abnormality in any of the readings obtained from any sensor, the ECU enters its back-up mode. In this event, the ECU ignores the abnormal sensor signal, and assumes a pre-programmed value which will allow the engine to continue running (albeit at reduced efficiency). If the ECU enters this back-up mode, the warning light on the instrument panel will come on, and the relevant fault code will be stored in the ECU memory. 8 If the warning light comes on, the vehicle should be taken to a Vauxhall dealer at the earliest opportunity. A complete test of the engine management system can then be carried out, using a special electronic diagnostic test unit which is simply plugged into the system’s diagnostic connector. The connector is located behind the fusebox cover panel on the drivers’ side of the facia. 2.0 litre DOHC engine models Simtec 56.1 or 56.5 system 9 All 2.0 litre DOHC engine models are equipped with a Simtec engine management (fuel injection/ignition) system (see illustration overleaf). The system is almost identical in operation to the Motronic system fitted to SOHC engines (see paragraphs 1 to 8). The only major change to the system is that a camshaft sensor is also incorporated into the system. The camshaft sensor informs the ECU of the speed and position of the exhaust camshaft. 10 In order to reduce exhaust emissions even further, a secondary air system is also incorporated. This is explained in greater detail in Part B of this Chapter. Fuel and exhaust systems 4A•5 4A 6.1 Engine management system component locations - 2.0 litre SOHC engine 1 Idle speed adjuster valve 2 Throttle potentiometer 3 Evaporative emission system purge valve 4 Exhaust gas recirculation (EGR) valve 5 6 7 8 9 Fuel pressure regulator DIS module Fuel pump relay Injection system relay Electronic control unit (ECU) 3510 Vauxhall/Opel Omega 10 11 12 13 14 Crankshaft sensor Coolant temperature sensor Knock sensor Intake air temperature sensor Airflow meter 4A•6 Fuel and exhaust systems 2.5 and 3.0 litre engines - Bosch Motronic M2.8.1 or 2.8.3 system 11 All 2.5 and 3.0 litre engine models are equipped with a Bosch Motronic engine management (fuel injection/ignition) system (see illustration). The system is almost identical in operation to the Motronic system fitted to 2.0 litre SOHC engine (see paragraphs 1 to 8). The only major change to the system is that a camshaft sensor is also incorporated into the system. The camshaft sensor is fitted to the left-hand cylinder bank informs the ECU of the speed and position of the exhaust camshaft. Due to the V6 layout of the engine there are two knock sensors and two oxygen sensors, one for each bank of cylinders. 12 In order to reduce exhaust emissions even 6.9 Engine management system component locations - 2.0 litre DOHC engine 1 2 3 4 5 Exhaust gas recirculation (EGR) valve DIS module Evaporative emission system purge valve Coolant temperature sensor Electronic control unit (ECU) 6 7 8 9 10 Fuel pump relay Injection system relay Crankshaft sensor Camshaft sensor Knock sensor 3510 Vauxhall/Opel Omega 11 12 13 14 15 Intake air temperature sensor Airflow meter Idle speed adjuster valve Throttle potentiometer Fuel pressure regulator Fuel and exhaust systems 4A•7 further, a secondary air system is also incorporated. This is explained in greater detail in Part B of this Chapter. 13 The ECU also has full control over the multiram air intake system described in Section 17. 14 On some later models the original M2.8.1 system was replaced with the later M2.8.3 system. The M2.8.3 system is identical in operation to the earlier system but incorporates an additional power steering system sensor which informs the ECU when load is being placed on the steering pump. Modifications to the injection/ignition settings within the ECU also result in more efficient engine operation. 4A 6.11 Engine management system component locations - 2.5 and 3.0 litre engine 1 2 3 4 5 6 Right-hand cylinder bank knock sensor Evaporative emission system purge valve Coolant temperature sensor DIS module Fuel pressure regulator Inlet manifold switchover valve solenoid valve 7 8 9 10 11 12 Inlet manifold switchover valve Idle speed adjuster valve Fuel pump relay Injection system relay Electronic control unit (ECU) Left-hand cylinder bank knock sensor 3510 Vauxhall/Opel Omega 13 14 15 16 17 18 Camshaft sensor Intake duct switchover valve Intake duct switchover valve solenoid valve Airflow meter Intake air temperature sensor Exhaust gas recirculation (EGR) valve 4A•8 Fuel and exhaust systems 7.2b On 2.5 and 3.0 litre engines the fuel valve (arrowed) is located at the rear of the inlet manifold 7.3 Place a wad of rag around the valve and depress the valve with a screwdriver to relieve the pressure in the fuel system 4 Once all pressure is relieved, securely refit the valve cap. Warning: Refer to the warning note in Section 1 before proceeding. The following procedure will merely relieve the pressure in the fuel system - remember that fuel will still be present in the system components, and take precautions accordingly before disconnecting any of them. 1 The fuel system referred to in this Section is defined as the tank-mounted fuel pump, the fuel filter, the fuel injectors and the pressure regulator, and the metal pipes and flexible hoses of the fuel lines between these components. All these contain fuel which will be under pressure while the engine is running, and/or while the ignition is switched on. The pressure will remain for some time after the ignition has been switched off, and it must be relieved in a controlled fashion when any of these components are disturbed for servicing work. 2 Locate the valve assembly which is fitted to the fuel rail on the inlet manifold. On 2.0 litre engines it can be found on the top of the rail and on 2.5 and 3.0 litre engines it is located at the rear of the fuel rail, directly below the breather hose connections on the rear of the inlet manifold upper section (see illustrations). 3 Unscrew the cap from the valve and position a container beneath the valve. Hold a wad of rag over the valve and relieve the pressure in the fuel system by depressing the valve core with a suitable screwdriver (see illustration). Be prepared for the squirt of fuel as the valve core is depressed and catch it with the rag. Hold the valve core down until no more fuel is expelled from the valve. 8.4 Undo the retaining screws (arrowed) and remove the access cover . . . 8.5 . . . then disconnect the wiring connector from the fuel pump cover 8.6 Release the retaining clips and disconnect the fuel hoses from the pump cover 8.7 Unscrew and remove the locking ring . . . 7.2a On 2.0 litre DOHC engines the fuel valve is located on the top of the fuel rail 7 Fuel injection system depressurisation 2 3510 Vauxhall/Opel Omega 8 Fuel pump removal and refitting 3 Warning: Refer to the warning note in Section 1 before proceeding. Note: A new fuel pump cover sealing ring will be required on refitting. Removal 1 Depressurise the fuel system as described in Section 7 then disconnect the battery negative lead. Note: On models with a Vauxhall antitheft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 On Saloon models lift up the luggage compartment carpet/floor to reveal the fuel pump access cover. 3 On Estate models lift up the luggage compartment floor then undo the fasteners and lift up the right-hand side section of the carpet to gain access to the fuel pump cover. If necessary, remove the CD autochanger as described in Chapter 12, Section 19. 4 Undo the retaining screws and remove the access cover from the floor to expose the fuel pump (see illustration). Recover the cover gasket; it should be renewed if it is damaged. 5 Disconnect the wiring connector from the fuel pump cover and tape the connector to the vehicle body to prevent it disappearing behind the tank (see illustration). 6 Mark the fuel hoses for identification purposes. Release the retaining clips and disconnect both hoses from the pump cover then plug the hose ends to minimise fuel loss (see illustration). Where the hoses are fitted with quick-release fittings, compress the clips located on each side of the fitting and ease the fitting off of its union. 7 Unscrew the locking ring and remove it from the tank (see illustration). This is best accomplished by using a screwdriver on the raised ribs of the locking ring. Tap the screwdriver to turn the ring anti-clockwise until it can be unscrewed by hand. Fuel and exhaust systems 4A•9 8.8a . . . then lift up pump cover and disconnect the wiring connector . . . 8.8b . . . and fuel hoses and remove the cover from the vehicle 8 Carefully lift the fuel pump cover away from tank then make alignment marks between the cover and hoses/wiring. Release the retaining clips then disconnect both the hose and wiring connectors and remove the cover from the vehicle along with its sealing ring (see illustrations). Discard the sealing ring; a new one must be used on refitting. 9 Release the three retaining clips by pressing them inwards then lift the fuel pump housing assembly out of the fuel tank using a piece of hooked welding rod engaged with the hole if the housing lug. As the pump is removed take great care not to displace the fuel filter which is fitted to the pump base and also try not to spill fuel onto the interior of the vehicle (see illustrations). 10 Inspect the fuel filter for signs of damage or deterioration and renew if necessary. 11 If necessary the pump housing assembly can be dismantled and the pump removed, noting the wiring connectors correct locations. Removal Refitting Refitting 12 Where necessary, reassembly the pump and housing components ensuring the wiring connectors are correctly and securely reconnected. 13 Ensure the filter is securely fitted to the base of the pump then carefully manoeuvre the pump assembly into position, making sure it clips securely into position. 14 Fit a new sealing ring to the tank. 15 Reconnect the fuel hoses and wiring connectors to the pump cover, using the marks made on removal to ensure they are correctly reconnected. Secure the hoses in position with the retaining clips then seat the pump cover on the tank. 16 Refit the locking ring to the fuel tank and tighten it securely. 17 Reconnect the fuel hoses to the pump cover, ensuring each fitting clicks securely into position, and reconnect the wiring connector. 18 Reconnect the battery then start the engine and check for fuel leaks. If all is well, refit the access cover and gasket then lay the luggage compartment carpet/floor back in position. 4 Manoeuvre the sender unit carefully in through the tank aperture and slide it into position on the side of the fuel pump reservoir. 5 Ensure the sender unit is clipped securely in position then refit the fuel pump cover as described in paragraphs 14 to 18 of Section 8. 9 Fuel gauge sender unit removal and refitting 8.9a Release the retaining clips and withdraw the pump housing assembly from the tank with a piece of welding rod 3 Warning: Refer to the warning note in Section 1 before proceeding. Note: A new fuel pump cover sealing ring will be required on refitting. 1 Carry out the operations described in paragraphs 1 to 8 of Section 8 to remove the fuel pump cover. 2 The fuel gauge sender unit is clipped to the side of the fuel pump mounting reservoir. Carefully release the retaining clip then slide the sender unit upwards to release it from its mounting. 3 Manoeuvre the sender unit through the fuel tank aperture, taking great care not damage the float arm (see illustration). 10 Fuel tank removal and refitting 3 8.9b Ensure the pump filter is clean and undamaged 2 Before removing the fuel tank, all fuel must be drained from the tank. Since a fuel tank drain plug is not provided, it is therefore preferable to carry out the removal operation when the tank is nearly empty. The remaining fuel can then be siphoned or hand-pumped from the tank. 3 Open up the fuel filler flap and remove the rubber cover from around the filler neck aperture. 4 Chock the front wheels then jack up the rear of the vehicle and support it on axle stands. Remove the right-hand rear roadwheel. 5 Remove the retaining screws and fasteners and remove the wheelarch liner from the rear, right-hand arch then proceed as described under the relevant sub-heading. Warning: Refer to the warning note in Section 1 before proceeding. Removal 1 Depressurise the fuel system as described in Section 7 then disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 3510 Vauxhall/Opel Omega 9.3 Removing the fuel gauge sender unit 4A 4A•10 Fuel and exhaust systems 10.6 On Saloon models disconnect the pump/gauge sender unit wiring connector (1) which is located at the front of the fuel tank (2 is tank mounting bolt) Saloon models 6 Locate the fuel pump/gauge sender unit wiring connector at the front of the fuel tank and disconnect the connector (see illustration). 7 Trace the filler neck vent hose back to its connection on the right-hand side of the tank. Slacken the retaining clip and disconnect the hose so that it is free to be removed with the tank. 8 Trace the fuel feed and return hoses from the tank to their unions in front of the tank then mark the fuel hoses for identification purposes. The hoses are equipped with quick-release fittings to ease removal. To disconnect each hose, compress the clips located on each side of the fitting and ease the fitting off of its union. Disconnect both hoses from the top of the pump, noting the correct fitted position of the sealing rings and plug the hose ends to minimise fuel loss. 9 Place a trolley jack with an interposed block of wood beneath the tank, then raise the jack until it is supporting the weight of the tank. 10 Slacken and remove the retaining nut and bolts and remove the two retaining straps from underneath the fuel tank. 11 Slowly lower the fuel tank out of position, disconnecting any other relevant vent pipes as they become accessible (where necessary), and remove the tank from underneath the vehicle. 12 If the tank is contaminated with sediment or water, remove the fuel pump cover (Section 8), and swill the tank out with clean fuel. The tank is injection-moulded from a synthetic material - if seriously damaged, it should be renewed. However, in certain cases, it may be possible to have small leaks or minor damage repaired. Seek the advice of a specialist before attempting to repair the fuel tank. 10.16 On Estate models locate the vent hose T-piece (arrowed) and disconnect the tank hoses retaining screws and remove access cover from the floor to expose the fuel pump cover. Recover the cover gasket; it should be renewed if it is damaged. 14 Disconnect the wiring connector from the fuel pump cover and tape the connector to the vehicle body to prevent it disappearing behind the tank. 15 Release the retaining clip and disconnect the vent hose from the rear of the fuel tank. 16 Locate the vent hose T-piece on the front, left-hand corner of the fuel tank. Free the Tpiece from its retaining clip then slacken the clips and detach both the tank hoses (see illustration). 17 Remove the fuel tank as described in paragraphs 7 to 13 (see illustration). Refitting 18 Refitting is the reverse of the removal procedure, noting the following points: a) When lifting the tank back into position, take care to ensure that none of the hoses become trapped between the tank and vehicle body. Refit the retaining straps and tighten the nut and bolts to the specified torque. b) Ensure all pipes and hoses are correctly routed and all hoses unions are securely joined. Estate models 13 Lift up the luggage compartment floor then remove the fasteners and lift up the righthand side section of the carpet to gain access to the fuel pump access cover. Undo the 10.17 Fuel tank retaining bolt Estate model 3510 Vauxhall/Opel Omega c) On completion, refill the tank with a small amount of fuel, and check for signs of leakage prior to taking the vehicle out on the road. 11 Throttle housing removal and refitting 4 2.0 litre SOHC engine models Removal 1 Disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Disconnect the wiring connectors from the intake air temperature sensor and the airflow meter. 3 Slacken the retaining clips then disconnect the intake duct from the air cleaner and throttle housing and remove the duct assembly from the engine compartment. 4 Remove the retaining clip and detach the accelerator cable from the throttle cam balljoint and unclip the cable from its mounting bracket. On models with cruise control it will also be necessary to remove the second retaining clip and detach the cruise control cable. 5 Undo the retaining bolts and free the cable mounting bracket from the manifold noting the correct fitted location of the spring. 6 Clamp the coolant hoses which are connected to the rear of the throttle body then release the retaining clips and disconnect both hoses. Wipe away any spilt coolant. 7 Disconnect the wiring connectors from the throttle potentiometer and the idle speed adjuster. 8 Disconnect the vacuum/breather hoses from the throttle body, noting their correct Fuel and exhaust systems 4A•11 11.11 Disconnect the wiring connectors from the intake air temperature sensor and the airflow meter (arrowed) 11.12a Disconnect the breather hose from the cylinder head cover . . . 11.12b . . . then release the retaining clips and remove the intake duct assembly from the engine compartment fitted locations, then undo the retaining nuts and remove the housing from the manifold. Remove the gasket and discard it, a new one should be used on refitting. 11 Disconnect the wiring connectors from the intake air temperature sensor and the airflow meter (see illustration). 12 Slacken the retaining clip and disconnect the intake duct breather hose from the cylinder head cover. Slacken the retaining clips then disconnect the intake duct from the air cleaner and throttle housing and remove the duct assembly from the engine compartment (see illustrations). 13 Remove the retaining clip and detach the accelerator cable from the throttle cam balljoint and unclip the cable from its mounting bracket. On models with cruise control it will also be necessary to remove the second retaining clip and detach the cruise control cable. 14 Unscrew the nut and disconnect the fuel feed hose from its union on the rear of the fuel rail. As the union nut is slackened, retain the pipe end fitting with an open-ended spanner to prevent any excess strain being placed on the pipe. Plug the hose and pipe ends to minimise fuel loss and prevent the entry of dirt then undo the retaining bolt securing the fuel pipe to the throttle housing bracket (see illustration). 15 Clamp the coolant hoses which are connected to the throttle housing then release the retaining clips and disconnect both hoses (see illustration). Wipe away any spilt coolant. 16 Disconnect the wiring connectors from the throttle potentiometer and the idle speed adjuster. 17 Disconnect the vacuum hose(s) from the throttle body, noting their correct fitted locations, then undo the retaining nuts and remove the housing from the manifold. Remove the gasket and discard it, a new one should be used on refitting. Refitting 9 Refitting is the reverse of removal, bearing in mind the following points. a) Ensure the mating surfaces are clean and dry then fit a new gasket and tighten the housing nuts to the specified torque. b) Ensure all hoses are correctly and securely reconnected. c) On completion adjust the accelerator cable as described in Section 3. 2.0 litre DOHC engine models Warning: Refer to the warning note in Section 1 before proceeding. Removal 10 Disconnect the battery negative terminal then depressurise the fuel system as described in Section 7. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 11.14 Unscrew the fuel feed pipe union nut (A) then undo the pipe retaining bolt (B) Refitting 18 Refitting is the reverse of removal, bearing in mind the following points. a) Ensure the mating surfaces are clean and dry then fit a new gasket and tighten the housing nuts to the specified torque. b) Ensure all hoses are correctly and securely reconnected. c) On completion adjust the accelerator cable as described in Section 3. 2.5 and 3.0 litre engines Removal 19 Remove the inlet manifold upper section as described in Section 15. 11.15 Release the retaining clips and disconnect the coolant hoses (arrowed) from the throttle housing 3510 Vauxhall/Opel Omega 4A 4A•12 Fuel and exhaust systems 2 If these checks fail to reveal the cause of the problem, the vehicle should be taken to a suitably-equipped Vauxhall dealer for testing. A wiring block connector is incorporated in the engine management circuit, into which a special electronic diagnostic tester can be plugged (see Section 6). The tester will locate the fault quickly and simply, alleviating the need to test all the system components individually, which is a time-consuming operation that carries a risk of damaging the ECU. 11.20 Removing the throttle housing 2.5 and 3.0 litre engines 20 Slacken and remove the retaining bolts and separate the throttle body from the manifold (see illustration). Recover the large sealing rings from the throttle body bores and the small rings from the manifold breather passages and discard them; new sealing rings should be used on refitting. Refitting 21 Fit new sealing rings to the manifold breather passages and the throttle body bores then carefully ease the throttle housing assembly into position on the manifold upper section, ensuring all the sealing rings remain correctly seated (see illustration). 22 Tighten the throttle body retaining bolts to the specified torque then refit the manifold upper section as described in Section 15. 12 Fuel injection system testing and adjustment Testing 1 If a fault appears in the fuel injection system, first ensure that all the system wiring connectors are securely connected and free of corrosion. Ensure that the fault is not due to poor maintenance; ie, check that the air cleaner filter element is clean, the spark plugs are in good condition and correctly gapped, the cylinder compression pressures are correct, and that the engine breather hoses are clear and undamaged, referring to Chapters 1 and 2A, 2B or 2C for further information (as applicable). 11.21 On refitting, fit new sealing rings to the throttle housing recesses Adjustment 3 Experienced home mechanics with a considerable amount of skill and equipment (including a tachometer and an accurately calibrated exhaust gas analyser) may be able to check the exhaust CO level and the idle speed. However, if these are found to be in need of adjustment, the car will have to be taken to a suitably-equipped Vauxhall dealer who has access to the necessary diagnostic equipment required to test and (where possible) adjust the settings. 13 Fuel injection system components (2.0 litre engine) - removal and refitting 4 Fuel injector Warning: Refer to the warning note in Section 1 before proceeding. Note: If a faulty injector is suspected, before condemning the injector, it is worth trying the effect of one of the proprietary injectorcleaning treatments. 6 Release the retaining clips and disconnect the wiring connectors from the injectors. 7 Unscrew the nut and detach the earth lead from the fuel rail rear retaining bolt. 8 Slacken and remove the retaining bolts then carefully ease the fuel rail and injector assembly out of position and remove it from the manifold. Remove the lower sealing rings from the injectors and discard them; they must be renewed whenever they are disturbed. 9 Slide off the relevant retaining clip and withdraw the injector from the fuel rail. Remove the upper sealing ring from the injector and discard it; all disturbed sealing rings must be renewed. 10 Refitting is a reversal of the removal procedure, noting the following points. a) Renew all disturbed sealing rings and apply a smear of engine oil to them to aid installation. b) Ease the injector(s) into the fuel rail, ensuring that the sealing ring(s) remain correctly seated, and secure in position with the retaining clips. c) On refitting the fuel rail, take care not to damage the injectors and ensure that all sealing rings remain in position. Once the fuel rail is correctly seated, tighten its retaining bolts to the specified torque. d) Fit new sealing washers to each side of the fuel feed and return hose unions then screw in the union bolts. Ensure both hose unions are correctly positioned then tighten the unions bolts to the specified torque. e) On completion start the engine and check for fuel leaks. Adjust the accelerator cable as described in Section 3. SOHC engine DOHC engine 1 Depressurise the fuel system as described in Section 7 then disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Disconnect the vacuum hoses from the inlet manifold and fuel pressure regulator and position the hose clear of the fuel rail. 3 Remove the retaining clip and detach the accelerator cable from the throttle cam balljoint and unclip the cable from its mounting bracket. On models with cruise control it will also be necessary to remove the second retaining clip and detach the cruise control cable. 4 Undo the retaining bolts and free the cable mounting bracket from the manifold noting the correct fitted location of the spring. 5 Unscrew the union bolts and disconnect the fuel feed and return hoses from the fuel rail. Recover the sealing washers from each hose union and discard; new ones should be used on refitting. 11 Depressurise the fuel system as described in Section 7 then disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 12 Release the retaining clips and disconnect the breather hoses from the right-hand side of the cylinder head cover. Also disconnect the vacuum hose from the fuel pressure regulator. 13 Disconnect the wiring connectors from the intake air temperature sensor and the airflow meter. 14 Slacken the retaining clips then disconnect the intake duct from the air cleaner and throttle housing and remove the duct assembly from the engine compartment, freeing it from the wiring harness. 15 Remove the retaining clip and detach the accelerator cable from the throttle cam balljoint and unclip the cable from its mounting bracket. On models with cruise control it will also be necessary to detach the cruise control cable. 3510 Vauxhall/Opel Omega Fuel and exhaust systems 4A•13 16 Unscrew the nuts and disconnect the fuel feed hose from its union on the rear of the fuel rail and the return pipe from the front end of the fuel rail. As the union nuts are slackened, retain the pipe end fitting with an open-ended spanner to prevent any excess strain being placed on the pipe. Plug the hose and pipe ends to minimise fuel loss and prevent the entry of dirt then undo the retaining bolt securing the fuel feed rail pipe to the throttle housing bracket (see illustrations). 17 Disconnect the wiring connector from the idle control stepper motor then undo the retaining bolts and free the cable mounting bracket from the throttle housing, noting the correct fitted location of the spring. 18 Unscrew the retaining nut and detach the earth lead from the fuel rail front retaining bolt. 19 Carefully release the retaining clips and lift off the injector wiring cover assembly squarely away from the top of the injectors; the wiring connectors are an integral part of the cover. Disconnect the crankshaft sensor and knock sensor wiring connectors (where necessary) from the underside of the injector wiring cover then position the cover assembly clear of the fuel rail. 20 Slacken and remove the retaining bolts then carefully ease the fuel rail and injector assembly out of position and remove it from the manifold. Remove the lower sealing rings from the injectors and discard them; they must be renewed whenever they are disturbed. 21 Slide off the relevant retaining clip and withdraw the injector from the fuel rail. Remove the upper sealing ring from the injector and discard it; all disturbed sealing rings must be renewed. 22 Refitting is a reversal of the removal procedure, noting the following points. a) Renew all disturbed sealing rings and apply a smear of engine oil to them to aid installation. b) Ease the injector(s) into the fuel rail, ensuring that the sealing ring(s) remain correctly seated, and secure in position with the retaining clips. Ensure that the retaining clips are correctly positioned otherwise it will not be possible to refit the wiring cover assembly. c) On refitting the fuel rail, take care not to damage the injectors and ensure that all sealing rings remain in position. Once the fuel rail is correctly seated, tighten its retaining bolts to the specified torque. d) On completion, adjust the accelerator cable as described in Section 3 then start the engine and check for fuel leaks. 13.16a Unscrew the fuel feed pipe union nut (A) and bolt (B) . . . (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 24 Disconnect the vacuum hose from the regulator (see illustration). 25 Slacken the retaining clamp then carefully ease the pressure regulator out from the top of the fuel rail. Remove the both sealing rings from the regulator and discard them; new ones must be used on refitting. 26 Refitting is the reverse of removal, using new sealing rings and lubricating them with a smear of engine oil to ease installation. Ensure the regulator is correctly positioned then tighten the retaining clamp screw to the specified torque. On completion start the engine and check for signs of fuel leakage. Idle speed adjuster valve 27 On DOHC engines, disconnect the wiring connectors from the intake air temperature sensor and the airflow meter then slacken the retaining clips then disconnect the intake duct from the air cleaner and throttle housing. Position the duct assembly clear of the throttle housing to improve access to the adjuster valve. 28 On all engines, disconnect the wiring connector then undo the retaining screws and remove the motor assembly from the side of the throttle housing. Remove the gasket and discard it; a new one should be used on refitting. 29 Refitting is the reverse of removal using a new gasket. 13.16b . . . and the fuel return pipe union nut Throttle potentiometer 30 Ensure the ignition is switched off then disconnect the wiring connector from the throttle potentiometer which is fitted to the throttle housing. 31 Slacken and remove the retaining screws then remove the potentiometer from the housing (see illustration). 32 Refitting is the reverse of removal making sure the potentiometer is correctly engaged with the throttle valve spindle. Coolant temperature sensor SOHC engine 33 The coolant temperature sensor is screwed into the front, right-hand end of the cylinder head. Refer to Chapter 3, Section 7 for removal and refitting details noting that it maybe necessary to unbolt the upper mounting brackets and pivot the alternator away from the cylinder block to gain the necessary clearance required to remove the sensor. DOHC engine 34 The coolant temperature sensor is screwed into the rear of the cylinder head where it is located beneath the DIS module. Refer to Chapter 3, Section 7 for removal and refitting details. Intake air temperature sensor 35 Ensure ignition is switched off then disconnect the wiring connector from the sensor. 36 Slacken the retaining clips then detach the intake duct from the airflow meter and air Fuel pressure regulator Warning: Refer to the warning note in Section 1 before proceeding. 23 Depressurise the fuel system as described in Section 7 then disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system 13.24 Fuel pressure regulator vacuum hose (1) and retaining clamp (2) 3510 Vauxhall/Opel Omega 13.31 Disconnect the wiring connector (1) then undo the retaining screws (2) and remove the throttle potentiometer 4A 4A•14 Fuel and exhaust systems 13.36a Disconnect the wiring connector from the intake air temperature sensor . . . 13.36b . . . then slacken the retaining clips and remove the intake duct cleaner housing and remove it from the vehicle (see illustrations). 37 Carefully ease the sensor out of position, taking great care not to damage the duct. 38 Refitting is the reverse of removal noting that the sensor must be fitted so that its flat edge aligns with the flat on the intake duct. Aid installation by lubricating the duct with a silicone-based spray. 45 On models with air conditioning, to improve access to the sensor remove the engine/transmission left-hand mounting and mounting bracket from the cylinder block (see Chapter 2A). 46 Work back along the sensor wiring and release it from all the relevant clips and ties whilst noting its correct routing. Disconnect the wiring connector so the wiring is free to be removed with the sensor. 47 Unscrew the retaining bolt and remove the sensor from the front of the cylinder block, along with its sealing ring. Discard the sealing ring, a new one should be used on refitting. 48 Refitting is the reverse of removal using a new sealing ring and tightening the sensor bolt to the specified torque. Ensure the wiring is correctly routed and retained by all the necessary clips before refitting the timing belt cover (see Chapter 2A). Airflow meter 39 Ensure the ignition is switched off then disconnect the wiring connector from the airflow meter and intake air temperature sensor (see illustration). 40 Slacken the retaining clips then detach the intake duct from the airflow meter and air cleaner housing and remove it from the vehicle. 41 Slacken the retaining clip then remove the airflow meter from the vehicle (see illustration). Inspect the meter for signs of damage and renew if necessary. 42 Refitting is the reverse of removal ensuring the intake ducts are correctly engaged with the meter recesses. Crankshaft sensor SOHC engine 43 Remove the timing belt front cover as described in Chapter 2A. The sensor is mounted on the left-hand side of the cylinder block, beneath the power steering pump. 44 To improve access, firmly apply the handbrake then jack up the front of the vehicle and support it securely on axle stands. Undo the retaining screws and remove the undercover from beneath the engine. 13.39 Disconnect the wiring connector from the airflow meter DOHC engine 49 The sensor is fitted to the left-hand side of the cylinder block, beneath the power steering pump. Removal and refitting is as follows. 50 Firmly apply the handbrake then jack up the front of the vehicle and support it securely on axle stands. Undo the retaining screws and remove the undercover from beneath the engine. 51 Trace the wiring back from the sensor, over the top of the cylinder head to its wiring connector. On early models the connector is connected to the underside of the front of the injector wiring cover assembly whereas on later models it is connected to the engine harness connector on the front of the engine. 52 Release the retaining clip and disconnect 13.41 Removing the airflow meter 3510 Vauxhall/Opel Omega the crankshaft sensor connector from the injector cover/engine harness (as applicable) (see illustration). On early models if the connector proves difficult to disconnect, free the injector wiring cover from the injectors as described earlier in this section then disconnect the connector. 53 Work along the sensor wiring, releasing it from all the relevant clips and ties whilst noting its correct routing. 54 On models with air conditioning, to improve access to the sensor remove the engine/transmission left-hand mounting and mounting bracket from the cylinder block (see Chapter 2B). 55 Unscrew the retaining bolt and remove the sensor from the front of the cylinder block, along with its sealing ring. Discard the sealing ring, a new one should be used on refitting. 56 Refitting is the reverse of removal using a new sealing ring and tightening the sensor bolt to the specified torque. Ensure the wiring is correctly routed and retained by all the necessary clips and ties. Knock sensor SOHC engine 57 The knock sensor is mounted onto the centre of the right-hand side of the cylinder block. To improve access, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands so the sensor can also be reached from below. 58 Ensure the ignition is switched off then disconnect the wiring connector from the sensor. 59 Slacken and remove the retaining bolt and remove the sensor from the engine. 60 On refitting ensure the mating surfaces are clean and dry. Fit the sensor then tighten its retaining bolt to the specified torque and reconnect the wiring connector. DOHC engine 61 The sensor is fitted to the centre of the right-hand side of the cylinder block. Removal and refitting is as follows. 62 Firmly apply the handbrake then jack up the front of the vehicle and support it securely on axle stands. Undo the retaining screws and remove the undercover from beneath the engine. 13.52 On later models the crankshaft sensor wiring connector (arrowed) is easily accessible Fuel and exhaust systems 4A•15 13.75a Slide out the ECU then lift the retaining clip . . . 13.75b . . . and disconnect its wiring connector 63 If necessary, to improve access, remove the starter motor as described in Chapter 5A. 64 Trace the wiring back from the sensor to its wiring connector. On early models the connector is connected to the underside of the injector wiring cover assembly (in between number 3 and 4 injectors) whereas on later models it is connected to the engine harness connector located on the underside of the inlet manifold. 65 Release the retaining clip and disconnect the crankshaft sensor connector from the injector cover/engine harness (as applicable). On early models if the connector proves difficult to disconnect, free the injector wiring cover from the injectors as described earlier in this section then disconnect the connector. 66 Work along the sensor wiring, releasing it from all the relevant clips and ties whilst noting its correct routing. 67 Slacken and remove the retaining bolt and remove the sensor from the engine. 68 On refitting ensure the mating surfaces are clean and dry then fit the sensor and tighten its retaining bolt to the specified torque. Ensure the wiring is correctly routed and securely reconnected. 72 Unscrew the retaining bolt and remove the camshaft sensor from the top of the cylinder head. 73 Refitting is the reverse of removal tightening the sensor retaining bolt to the specified torque. Camshaft sensor - DOHC engine 69 Undo the retaining screws and remove the spark plug cover from the top of the cylinder head cover. 70 Ensure the ignition is switched off then disconnect the wiring connector from the camshaft sensor. 71 Remove the timing belt front cover as described in Chapter 2B. 13.79 Removing the fuel pump relay Electronic control unit (ECU) 74 Disconnect the battery negative terminal then unclip the lid from the engine compartment relay box. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 75 Slide the ECU out of position until access to the wiring connector retaining clip can be gained. Lift the retaining clip and carefully disconnect the wiring connector then remove the ECU from the vehicle (see illustrations). If necessary, undo the retaining nuts and separate the ECU from its mounting plate. 76 Refitting is the reverse of removal making sure the wiring connector is correctly reconnected. On later DOHC engines (with Simtec 56.5 system) if a new ECU has been fitted it will be necessary to take the vehicle to a Vauxhall dealer to have the unit coded to match the performance of your engine. 13.78 The fuel pump relay (1) and injection system relay (2) are located in the engine compartment relay box relay is the right-hand (inner) relay of the two and the injection system/protection relay is the left-hand (outer) relay (see illustration). 79 Ensure the ignition is switched off then pull the relevant relay out of its socket and remove it from the vehicle (see illustration). 80 Refitting is the reverse of removal. Air conditioning system switch 81 The air conditioning system switch is screwed into one of the refrigerant pipes and cannot be removed without first discharging the refrigerant (see Chapter 3). Renewal of the switch should therefore be entrusted to a suitably equipped garage. 14 Fuel injection system components (2.5 and 3.0 litre engines) removal and refitting 4 Fuel injector 77 The injection system relays are located in the engine compartment relay box. 78 Unclip the lid from the relay box. The injection system relays are the two relays situated at the rear of the box; the fuel pump Warning: Refer to the warning note in Section 1 before proceeding. Note: If a faulty injector is suspected, before condemning the injector, it is worth trying the effect of one of the proprietary injectorcleaning treatments. 1 Remove the lower section of the inlet manifold as described in Section 15. 2 Depress the retaining clips and disconnect the wiring connectors from the six injectors. Unclip the wiring harness cover from the top of the fuel rail and remove it from the manifold (see illustrations). 14.2a Disconnect the wiring connectors from the injectors . . . 14.2b . . . then unclip the cover assembly from the fuel rail Injection system relays 3510 Vauxhall/Opel Omega 4A 4A•16 Fuel and exhaust systems 14.3a Slacken the union nuts . . . 14.3b . . . then undo the retaining bolts (arrowed) . . . 14.3c . . . and remove the fuel pipes from the manifold 3 Slacken the union nuts securing the fuel pipes to the fuel rail whilst (where possible) retaining the fuel rail with an open-ended spanner. Unscrew the retaining bolts and remove the pipe assembly from the manifold lower section (see illustrations). 4 Slacken and remove the retaining bolts then carefully ease the fuel rail and injector assembly out from the manifold. Remove the lower sealing rings from the injectors and discard them. Slide off the relevant retaining clip and withdraw the injector from the fuel rail. Remove the upper sealing ring from the injector and discard it. All disturbed sealing rings must be renewed (see illustrations). 5 Refitting is a reversal of the removal procedure, noting the following points. a) Renew all disturbed sealing rings and apply a smear of engine oil to them to aid installation (see illustration). b) Ease the injector(s) into the fuel rail, ensuring that the sealing ring(s) remain correctly seated, and secure in position with the retaining clips. c) On refitting the fuel rail, take care not to damage the injectors and ensure that all sealing rings remain in position. Once the fuel rail is correctly seated, tighten its retaining bolts to the specified torque. d) Tighten the fuel pipe union nuts and retaining bolts to the specified torque then refit the wiring cover assembly making sure all the wiring connectors are securely reconnected. e) Refit the manifold as described in Section 15. On completion start the engine and check for fuel leaks. 6 Depressurise the fuel system as described in Section 7 then disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 7 To gain access to the pressure regulator, remove the windscreen wiper arms and the water deflector panel from the base of the windscreen (see Chapter 12, Sections 15 and 16) (see illustration). 8 Unclip the wiring connector holder from the lifting bracket on the rear of the cylinder head and position the wiring clear of the regulator. 9 Disconnect the vacuum hose from the fuel pressure regulator. 10 Slacken the retaining clamp then carefully ease the pressure regulator out from the fuel rail. Remove both sealing rings from the Fuel pressure regulator Warning: Refer to the warning note in Section 1 before proceeding. 14.4a Undo the retaining bolts (arrowed) . . . 14.4b . . . and ease the fuel rail and injector assembly out of position 14.4c Slide off the relevant retaining clip . . . 14.4d . . . then ease the injector out from the fuel rail 14.5 On refitting be sure to renew all injector sealing rings 14.7 The fuel pressure regulator is located at the rear of the inlet manifold (shown with engine removed) 3510 Vauxhall/Opel Omega Fuel and exhaust systems 4A•17 14.12 Disconnect the wiring connector from the idle speed adjuster valve . . . 14.13 . . . then release the retaining clip and detach the air hose 14.15 Disconnecting the throttle potentiometer wiring connector regulator and discard them; new ones must be used on refitting. 11 Refitting is the reverse of removal, using new sealing rings and lubricating them with a smear of engine oil to ease installation. Ensure the regulator is correctly positioned then securely tighten the retaining clamp screw. On completion start the engine and check for signs of fuel leakage. 16 Slacken and remove the retaining screws then remove the potentiometer from the housing. 17 Refitting is the reverse of removal making sure the potentiometer is correctly engaged with the throttle valve spindle. airflow meter and intake air temperature sensor. 24 Slacken the retaining clips then detach the intake duct from the airflow meter and air cleaner housing and remove it from the vehicle. 25 Slacken the retaining clip then remove the airflow meter from the vehicle. Inspect the meter for signs of damage and renew if necessary. 26 Refitting is the reverse of removal ensuring the intake ducts are correctly engaged with the meter recesses. Idle speed adjuster valve 12 Ensure the ignition is switched off then disconnect the wiring connector from the valve which is fitted to the left-hand side of the inlet manifold (see illustration). 13 Slacken the retaining clip and disconnect the hose from the valve then carefully ease the valve assembly out from the manifold (see illustration). If necessary separate the valve and its mounting rubber. Inspect the mounting rubber for signs of damage or deterioration and renew if necessary. 14 Refitting is the reverse of removal making sure the mounting rubber grommet is correctly positioned. Aid installation by lubricating the grommet with a silicone-based spray. On completion start the engine and check for air leaks. Throttle potentiometer 15 Ensure the ignition is switched off then disconnect the wiring connector from the throttle potentiometer which is fitted to the left-hand side of the throttle housing (see illustration). 14.18 The coolant temperature sensor is screwed into the coolant outlet (shown with inlet manifold removed) Coolant temperature sensor 18 The coolant temperature sensor is screwed into the coolant outlet which links the rear of the cylinder heads. Refer to Chapter 3 for removal and refitting details noting that it will be necessary to remove the inlet manifold to gain access to the sensor (see illustration). Crankshaft sensor 23 Ensure the ignition is switched off then disconnect the wiring connectors from the 27 The sensor is mounted on the left-hand side of the cylinder block, directly below the oil filter, and its wiring connector is clipped onto the holder on the rear of the left hand cylinder head. 28 To gain access to the wiring connector, remove the windscreen wiper arms and the water deflector panel from the base of the windscreen (see Chapter 12, Sections 15 and 16). 29 Ensure the ignition is switched off then unclip the sensor wiring connector from its holder and disconnect it (see illustration). 30 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 31 Work back along the sensor wiring and release it from all the relevant clips and ties whilst noting its correct routing. 32 Unscrew the retaining bolt and remove the sensor from the cylinder block, along with 14.20 Disconnect the wiring connector from the intake air sensor then release the retaining clips (arrowed) and remove the intake duct 14.29 The crankshaft sensor wiring connector (arrowed) is clipped onto the engine rear lifting bracket (shown with engine removed) Intake air temperature sensor 19 Ensure ignition is switched off then disconnect the wiring connector from the sensor. 20 Slacken the retaining clips then detach the intake duct from the airflow meter and air cleaner housing and remove it from the vehicle (see illustration). 21 Carefully ease the sensor out of position and recover is sealing grommet. Inspect the grommet for signs of damage or deterioration and renew if necessary. 22 Refitting is the reverse of removal making sure the sensor and grommet are correctly seated. Airflow meter 3510 Vauxhall/Opel Omega 4A 4A•18 Fuel and exhaust systems retained by all the necessary clips so that it is no danger of contacting the exhaust system or auxiliary drivebelt. On models with air conditioning refit the engine mounting bracket and mounting as described in Chapter 2C. Camshaft sensor 14.32 Removing the crankshaft sensor (shown with oil filter removed) its sealing ring. Discard the sealing ring, a new one should be used on refitting (see illustration). 33 Refitting is the reverse of removal using a new sealing ring and tightening the sensor bolt to the specified torque. Ensure the wiring is correctly routed and retained by all the necessary clips so that it is in no danger of contacting the exhaust manifold. Knock sensor right-hand cylinder bank 34 Remove the auxiliary drivebelt as described in Chapter 1 then unbolt the drivebelt tensioner pulley assembly from the side of the cylinder head. 35 Remove the alternator upper mounting bolt then slacken the lower mounting and pivot the alternator away from the block (see Chapter 5A). 36 Trace the wiring back from the sensor to the front of the timing belt cover, releasing it from all the relevant clips and ties whilst noting its correct routing. Ensure the ignition is switched off then disconnect the sensor wiring connector. 37 Slacken and remove the retaining bolt and remove the sensor from the engine (see illustration). 38 On refitting ensure the mating surfaces are clean and dry then fit the sensor and tighten its retaining bolt to the specified torque. Ensure the wiring is correctly routed and securely retained by all the necessary clips so that it is no danger of contacting the auxiliary drivebelt. Refit the alternator and 14.43 On refitting ensure the knock sensor is correctly positioned then tighten its retaining bolt to the specified torque 14.37 Unscrew the retaining bolt and remove the knock sensor from the righthand side of the cylinder block drivebelt tensioner, tightening their retaining bolts to the specified torque settings (see Chapter 5A) and refit the auxiliary drivebelt (see Chapter 1). Knock sensor left-hand cylinder bank 39 The knock sensor is situated on the lefthand side of the cylinder block, just in front of the oil filter and is wiring connector is connected to the wiring harness cover above the left-hand cylinder head. To gain access to the sensor, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 40 On models with air conditioning, to improve access to the sensor remove the engine/transmission left-hand mounting and mounting bracket from the cylinder block (see Chapter 2C). 41 Trace the wiring back from the sensor, releasing it from all the relevant clips and ties whilst noting its correct routing. Disconnect the wiring connector and tie a length of string to it; the string can then be used on refitting to draw the wiring connector up and into position. 42 Slacken and remove the retaining bolt and remove the sensor from the engine. Untie the string and leave in position for use on refitting. 43 On refitting then use the string to draw the wiring connector up and into position. Ensure the mating surfaces are clean and dry then fit the sensor and tighten its retaining bolt to the specified torque (see illustration). Ensure the wiring is correctly routed and securely 14.46 Removing the camshaft sensor 3510 Vauxhall/Opel Omega 44 The sensor is mounted onto the top of the left-hand cylinder bank exhaust camshaft where it is directly behind the timing belt cover. On models with air conditioning, to improve access to the sensor, unbolt the air conditioning pipe/hose bracket from the cylinder head and position the hose/pipe to one side. 45 Ensure the ignition is switched off then disconnect the wiring connector from the camshaft sensor 46 Unscrew the retaining bolt and remove the camshaft sensor from the camshaft bearing cap (see illustration). 47 Refitting is the reverse of removal tightening the sensor retaining bolt to the specified torque. Electronic control unit (ECU) 48 Refer to Section 13. Injection system relays 49 Refer to Section 13. Air conditioning system switch 50 The air conditioning system switch is screwed into one of the refrigerant pipes and cannot be removed without first discharging the refrigerant (see Chapter 3). Renewal of the switch should therefore be entrusted to a suitably equipped garage. 15 Inlet manifold removal and refitting 4 Warning: Refer to the warning note in Section 1 before proceeding. 2.0 litre SOHC engine Removal 1 Depressurise the fuel system as described in Section 7 then disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Remove the auxiliary drivebelt and drain the cooling system as described in Chapter 1. 3 Disconnect the wiring connectors from the intake air temperature sensor and the airflow meter. 4 Slacken the retaining clips then disconnect the intake duct from the air cleaner and throttle housing and remove the duct assembly from the engine compartment. 5 Remove the retaining clip and detach the Fuel and exhaust systems 4A•19 accelerator cable from the throttle cam balljoint and unclip the cable from its mounting bracket. On models with cruise control it will also be necessary to remove the second retaining clip and detach the cruise control cable. 6 Undo the retaining bolts and free the cable mounting bracket from the manifold noting the correct fitted location of the spring. 7 Undo the retaining bolts and remove the support bracket and alternator mounting bracket from the front of the manifold. 8 Unscrew the union bolts and disconnect the fuel feed and return hoses from the fuel rail. Recover the sealing washers from each hose union and discard; new ones should be used on refitting. Plug the hose ends to minimise fuel loss and prevent the entry of dirt into the system. 9 Disconnect the wiring connectors from the throttle potentiometer, the idle speed adjuster valve, the injectors, the purge valve, the DIS module and the exhaust gas recirculation (EGR) valve. 10 Unscrew the nut/bolt and detach the earth leads from the fuel rail rear retaining bolt and camshaft housing. 11 Note the correct routing of the wiring then undo the wiring cover retaining bolts and position the cover assembly clear of the inlet manifold. 12 Disconnect the various breather/vacuum hoses from the throttle housing and manifold (as applicable) noting each ones correct fitted location. 13 Slacken the retaining clips and disconnect the coolant hose from the throttle housing. 14 Unscrew the union nut and disconnect the braking system servo unit hose from the manifold. 15 Check that all the necessary vacuum/breather hoses have been disconnected then slacken and remove the manifold retaining nuts. 16 Remove the manifold from the engine and recover the manifold gasket, noting which way around it is fitted. Refitting 17 Refitting is the reverse of removal bearing in mind the following points. a) Prior to refitting, check the manifold studs and renew any that are worn or damaged. b) Ensure the manifold and cylinder mating surfaces are clean and dry and fit the new gasket. Refit the manifold and tighten the retaining nuts evenly and progressively to the specified torque. c) Ensure that all relevant hoses are reconnected to their original positions, and are securely held (where necessary) by their retaining clips. d) Fit new sealing washers to each side of the fuel feed and return hose unions then screw in the union bolts. Ensure both hose unions are correctly positioned then tighten the unions bolts to the specified torque. e) Tighten all fixings to their specified torque setting (where given). f) Refit the auxiliary drivebelt and refill the cooling system as described in Chapter 1. g) On completion, adjust the accelerator cable as described in Section 3. 2.0 litre DOHC engine Note: New manifold retaining will be required on refitting. Removal 18 Remove the auxiliary drivebelt and drain the cooling system as described in Chapter 1. 19 Remove the throttle housing as described in Section 11. 20 Unscrew the nut and disconnect the fuel return pipe from the end of the fuel rail. As the union nuts are slackened, retain the pipe end fitting with an open-ended spanner to prevent any excess strain being placed on the pipe. Plug the hose and pipe end to minimise fuel loss and prevent the entry of dirt. 21 Unscrew the retaining nut and detach the earth lead from the fuel rail front retaining bolt. 22 Carefully release the retaining clips and lift off the injector wiring cover assembly squarely away from the top of the injectors; the wiring connectors are an integral part of the cover. Disconnect the crankshaft sensor and knock sensor wiring connectors (where necessary) from the injector wiring cover then position the cover assembly clear of the manifold. 23 Unscrew the union nut and disconnect the braking system servo unit hose from the manifold. 24 Disconnect all remaining vacuum/breather hoses from the manifold, noting each ones correct fitted location. 25 Undo the retaining bolts and remove the alternator mounting brackets from the front of the inlet manifold. 26 Undo the retaining bolts and remove the support bracket from the base of the manifold. 27 Slacken and remove the retaining nuts and bolts and manoeuvre the manifold assembly away from the engine. Remove the gasket and discard it also discard the manifold nuts; new ones should be used on refitting. 15.30 Slacken the retaining clip and detach the air hose from the idle speed adjuster valve e) Refit the auxiliary drivebelt and refill the cooling system as described in Chapter 1. f) On completion, adjust the accelerator cable as described in Section 3. 2.5 and 3.0 litre engines Removal Note: If only the upper section is to be removed carry out the operations described in paragraphs 29 to 39. 29 Disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 30 Slacken the retaining clip and disconnect the inlet hose from the idle speed adjuster (see illustration). 31 Slacken the retaining clips securing the intake ducts to the throttle housing and intake pre-volume valve and remove both ducts. 32 Remove the retaining clip and detach the accelerator cable from the throttle cam balljoint then unclip the cable from its mounting bracket. On models with cruise control it will also be necessary to remove the second retaining clip and detach the cruise control cable (see illustrations). 33 Clamp the coolant hoses which are connected to the throttle housing then release the retaining clips and disconnect both hoses (see illustration). Wipe away any spilt coolant. Refitting 28 Refitting is the reverse of removal noting the following. a) Prior to refitting, check the manifold studs and renew any that are worn or damaged. b) Ensure the manifold and cylinder mating surfaces are clean and dry and fit the new gasket. Refit the manifold then fit the retaining bolts and new nuts tightening them evenly and progressively to the specified torque. c) Ensure that all relevant hoses are reconnected to their original positions, and are securely held (where necessary) by their retaining clips. d) Tighten all fixings to their specified torque setting (where given). 3510 Vauxhall/Opel Omega 15.32a Remove the retaining clip and detach the accelerator inner cable from the throttle cam 4A 4A•20 Fuel and exhaust systems 15.32b On models with cruise control prise off the second retaining clip . . . 15.32c . . . and free the cruise control cable from the throttle cam and bracket 15.33 Release the retaining clips and detach the coolant hoses (arrowed) from the throttle housing 34 Disconnect the wiring connectors from the throttle valve potentiometer, the idle speed adjuster, the inlet manifold switchover valve solenoid and the exhaust gas recirculation (EGR) valve. 35 Unscrew the union nut and disconnect the pipe from the EGR valve then unscrew the retaining bolt and free the pipe bracket from the valve (see illustrations). Where necessary, disconnect the connector and free the knock sensor wiring connector from the EGR valve bracket. 36 Unscrew the union nut and disconnect the braking system servo unit vacuum hose from the manifold upper section (see illustration). 37 Make a note of the correct fitted locations of the vacuum/breather hoses connected to the rear of the manifold upper section then release the retaining clips (where fitted) and disconnect them (see illustration). 38 Unscrew the retaining bolts and detach the hose/wiring brackets from the corners of the manifold upper section (see illustration). 39 Remove the caps from the top of the manifold then slacken and remove the upper section retaining bolts. Lift off the manifold upper section, disconnecting the vacuum hoses from the manifold switchover solenoid valve as they become accessible (see illustrations). Remove the sealing rings from the top of manifold lower section and discard them; new ones should be used on refitting. Caution: Take great care not to allow any foreign object to drop down into the cylinder head intake ports. 40 Depressurise the fuel system (Section 7) then unscrew the nuts and disconnect the fuel feed and return hoses from their unions on the right-hand side of the manifold. As each union nut is slackened, retain the pipe end fitting with an open-ended spanner to prevent any excess strain being placed on the pipes (see illustration). Plug the hose and pipe ends to minimise fuel loss and prevent the entry of dirt. 15.35b . . . then remove the bracket retaining bolt 15.36 Unscrew the union nut and disconnect the braking system servo unit hose 15.37 Release the retaining clips and disconnect the vacuum and breather hoses from the rear of the manifold 15.38 Undo the retaining bolts and free the hose/wiring brackets from the manifold 15.39a Remove the caps then unscrew the retaining bolts . . . 15.39b . . . and remove the manifold upper section 15.35a Unscrew the union nut and free the EGR pipe from the EGR valve 3510 Vauxhall/Opel Omega Fuel and exhaust systems 4A•21 15.40 Unscrew the union nuts and disconnect the fuel feed and return hoses from the manifold 15.41 The injector wiring harness connector (arrowed) is clipped onto the engine rear lifting bracket (shown with engine removed) 41 Disconnect the injector wiring harness connector and the vacuum hose from the fuel pressure regulator (see illustration). 42 Slacken and remove the retaining bolts then lift the manifold lower section away from the cylinder head. Remove the seals from the manifold flange recesses and discard them; new ones must be used on refitting (see illustrations). 43 If necessary, undo the retaining bolts and remove the intake manifold flange from the top of the cylinder head (see illustration). Recover the flange seals and discard them; new ones must be used on refitting. Note: New manifold nuts will be required on refitting. Refitting 2.0 litre SOHC engine 44 Refitting is the reverse of removal noting the following. a) Ensure all the mating surfaces are clean and dry and the new seals/sealing rings are correctly seated in their recesses (see illustration). Tighten all the manifold retaining bolts evenly and progressively to their specified torque settings. b) Ensure that all relevant hoses are reconnected to their original positions, and are securely held (where necessary) by their retaining clips. c) Tighten the fuel hose and vacuum servo hose union nuts to their specified torque settings. d) Ensure the EGR valve and pipe mating surfaces are clean and dry and apply a smear of high-temperature grease to the threads of the union nut (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer). 15.42b . . . and recover the seals (arrowed) from the flange Reconnect the pipe to the valve and tighten its union nut to the specified torque. e) On completion, adjust the accelerator cable as described in Section 3. 16 Exhaust manifold removal and refitting 4 Removal 1 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. If necessary, to improve access undo the retaining bolts and remove the undercover from beneath the engine. 2 Slacken and remove the bolt(s) securing the exhaust system front pipe to its mounting bracket then unscrew the bolts securing the front pipe to the manifold. Free the pipe from the manifold taking care not to place any strain on the oxygen sensor wiring. Discard the front pipe gasket; a new one should be used on refitting. 3 Undo the retaining bolts and remove the heatshield from the exhaust manifold. 4 Remove the engine oil dipstick and pull the plug caps off from the centre (No 2 and 3) spark plugs. Unscrew the centre spark plug heatshields and remove them from the 15.43 Removing the manifold flange 3510 Vauxhall/Opel Omega 15.42a Remove the manifold lower section . . . manifold (a special socket, number KM-834, is available to ease removal of the heatshields). 5 Undo the retaining nuts securing the manifold to the head. Manoeuvre the manifold out of the engine compartment, complete with the gasket. Discard both the gasket and retaining nuts; new ones should be used on refitting. Refitting 6 Examine all the exhaust manifold studs for signs of damage and corrosion; remove all traces of corrosion, and repair or renew any damaged studs. 7 Ensure that the manifold and cylinder head sealing faces are clean and flat, and fit the new gasket. 8 Refit the manifold then fit the new retaining nuts and tighten them to the specified torque. 9 Apply a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer) to the threads of the spark plug heatshields then refit the shields and tighten them to the specified torque. Reconnect the plug caps and refit the dipstick. 10 Apply the high-temperature grease to the heatshield bolts then refit the heatshield to the manifold and securely tighten the bolts. 11 Fit a new gasket to the exhaust front pipe joint and lubricate the front pipe to manifold bolts with the high-temperature grease. Refit the bolts to the manifold, tightening them to the specified torque, then securely tighten the bolt(s) securing the front pipe to its mounting bracket. 15.44 On refitting be sure to renew all manifold seals and sealing rings 4A 4A•22 Fuel and exhaust systems 16.20 Disconnect the wiring connectors from the coolant sensor and sender . . . 16.21 . . . then release the retaining clips and disconnect the coolant hoses 16.22 Unscrew the retaining bolts and remove the coolant outlet from the engine (sealing rings arrowed) 15 Refit the manifold as described in paragraphs 6 to 8. 16 Fit a new gasket to the exhaust front pipe joint and lubricate the front pipe to manifold bolts with high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer). 18 Remove the inlet manifold and flange as described in Section 15. 19 Drain the cooling system as described in Chapter 1. 20 Disconnect the wiring connectors from the coolant temperature gauge sender and the engine management system coolant temperature sensor which are screwed into the coolant outlet which links the rear of the cylinder heads (see illustration). 16.24a Unscrew the union nuts securing the oil pipes to the block . . . 16.24b . . . then unscrew the union bolts and detach the pipes from the oil cooler (sealing washers arrowed) 21 Slacken the retaining clips and disconnect the coolant hoses from the cylinder head outlet (see illustration). 22 Unscrew the retaining bolts and remove the coolant outlet from the cylinder heads (see illustration). Recover the sealing rings and discard them; new ones must be used on refitting. 23 Position a container beneath the oil filter. Unscrew the filter using an oil filter removal tool if necessary, and drain the oil into the container. If the oil filter is damaged or distorted during removal, it must be renewed. Given the low cost of a new oil filter relative to the cost of repairing the damage which could result if a re-used filter springs a leak, it is probably a good idea to renew the filter in any case. 24 Unscrew the union nuts securing the oil cooler pipes to the cylinder block then unscrew the union bolts securing the pipes to the cooler. Recover the sealing washers from each side of the oil cooler unions and move the pipes to the rear (see illustrations). 25 Release the retaining clips and disconnect the radiator bottom hose, expansion tank hose and heater hose from the coolant pipe on the right-hand side of the engine. Slacken and remove the retaining bolts then remove the pipe from the engine (see illustration). Recover the sealing ring and discard it; a new one should be used on refitting. Note that it maybe necessary to remove the camshaft cover from the righthand cylinder head to gain the clearance required to remove the coolant pipe. 26 Undo the retaining bolts and remove the heatshields from the exhaust manifold (see illustrations). 16.26a Undo the retaining bolts and remove the lower . . . 16.26b . . . and upper heatshields from the right-hand exhaust manifold 2.0 litre DOHC engine Removal 12 Remove the secondary air injection system air valve and connecting pipe as described in Chapter 4B. 13 Carry out the operations described in paragraphs 1 and 2. 14 Undo the retaining nuts then remove the exhaust manifold and gasket from the cylinder head. Discard both the gasket and retaining nuts; new ones should be used on refitting. Refitting 16.25 Removing the engine coolant pipe Refit the bolts to the manifold, tightening them to the specified torque, then securely tighten the bolt(s) securing the front pipe to its mounting bracket. 17 Refit the secondary air injection system connecting pipe and air valve as described in Chapter 4B. 2.5 and 3.0 litre engine Right-hand cylinder bank 3510 Vauxhall/Opel Omega Fuel and exhaust systems 4A•23 27 Slacken and remove the bolt securing the exhaust system right-hand front pipe to its mounting bracket then unscrew the bolts securing the pipe to the manifold. Free the pipe from the manifold taking care not to place any strain on the oxygen sensor wiring, and recover the gasket. Discard the front pipe gasket; a new one should be used on refitting. 28 Unscrew the union nuts and remove the pipe connecting the exhaust gas recirculation (EGR) valve to the manifold. 29 Slacken the clip securing the connecting hose to the right-hand cylinder bank secondary air injection system pipe then unscrew the bolts securing the pipe to the manifold. Remove the pipe from the vehicle and discard its gaskets (see illustration). 30 Undo the retaining nuts then remove the exhaust manifold and gasket from the cylinder head. Discard both the gasket and retaining nuts; new ones should be used on refitting. 31 Refitting is the reverse of removal, noting the following points. a) Prior to refitting, check the manifold studs and renew any that are worn or damaged. b) Ensure all mating surfaces are clean and dry and use new gaskets, sealing rings and washers. c) Secure the manifold in position with new retaining nuts, tightening them evenly and progressively to the specified torque. d) Prior to refitting, lubricate the threads of the secondary air injection system pipe bolts, the EGR valve pipe nuts, the front pipe to manifold bolts and the heatshield bolts with a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer). e) Tighten all fixings to their specified torque setting (where given). f) Ensure that all relevant hoses are reconnected to their original positions, and are securely held (where necessary) by their retaining clips. g) Fit new sealing washers to each side of the oil cooler pipe unions and tighten the pipe union nuts and bolts to the specified torque. i) Fit a new oil filter and refill the cooling system as described in Chapter 1. j) On completion, check the engine oil level as described in Weekly checks. 16.29 Undo the retaining bolts and remove the secondary air connecting pipe the bolt and spacer securing the coolant pipe and engine lifting bracket to the cylinder head and remove the lifting bracket. Free the coolant pipe from the thermostat housing then manoeuvre it out of position then withdraw the dipstick and ease the dipstick tube out from the cylinder block. Discard the coolant pipe and dipstick tube sealing rings; new ones should be used on refitting. 35 Undo the retaining bolts and remove the heatshields from the exhaust manifold. 36 Unscrew the retaining bolts and remove the secondary air injection system pipe from the manifold. Recover the gaskets fitted between the pipe and manifold and discard them. 37 Undo the retaining nuts then remove the exhaust manifold and gasket from the cylinder head. Discard both the gasket and retaining nuts; new ones should be used on refitting. 38 Refitting is the reverse of removal, noting the following points. a) Prior to refitting, check the manifold studs and renew any that are worn or damaged. b) Ensure the manifold and cylinder head mating surfaces are clean and dry then fit the new gasket. Refit the manifold then fit the new retaining nuts, tightening them evenly and progressively to the specified torque. c) Lubricate the threads of the secondary air injection system pipe bolts with a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer). Fit Left-hand cylinder bank 32 It is not possible to remove the exhaust manifold from the left-hand cylinder bank with the engine in the vehicle. This leaves two possible options, the first is to remove the engine unit from the vehicle and the second is to remove the cylinder head assembly. Decide on the course of action which is best suited then proceed as follows. 33 Working as described in Chapter 2C, either remove the engine unit from the vehicle or alternatively remove the cylinder head assembly from the engine. 34 If the engine has been removed, unscrew new gaskets to the pipe unions then refit the pipe to the cylinder head and tighten the retaining bolts to the specified torque (see Chapter 4B). d) Lubricate the manifold heatshield bolts with the high-temperature grease before installation. e) If the engine was removed, fit new sealing rings to the dipstick tube and thermostat housing coolant pipe. Ensure the coolant pipe, dipstick tube and lifting bracket are correctly positioned before refitting the retaining bolt and spacer and tightening to the specified torque. 17 Multi-ram air intake system information and component removal and refitting 3 Information 1 All 2.5 and 3.0 litre engines are fitted with a multi-ram air intake system to help increase torque output at all engine speeds. The system consists of the pre-volume chamber, which splits the air cleaner intake duct into two separate ducts, and two valves, one linking the intake ducts in between the prevolume chamber and throttle housing, and the second linking the left- and right-hand chambers of the inlet manifold upper section. Each valve is controlled the engine management ECU via a solenoid valve and vacuum diaphragm unit. 2 There are four possible combinations of valve position, each of which is suited to a particular engine speed range, they are as follows. a) Idle speed - intake duct valve closed, manifold valve open b) Full load at low engine speeds - intake duct and manifold valves both closed. c) Full load at medium engine speeds intake duct valve open, manifold valve closed. d) Full load at high engine speeds - intake valve and manifold valve both open. 3 Testing of the system can only be carried out using the special electronic diagnostic test unit which is plugged into the system’s diagnostic connector (see Section 6). The multi-ram intake system components can be removed and refitted as follows. Component removal and refitting Intake duct switchover valve solenoid valve 17.4 The intake duct switchover valve solenoid valve (arrowed) is mounted on the rear of the pre-volume chamber (shown with chamber removed) 3510 Vauxhall/Opel Omega 4 The intake duct switchover valve solenoid valve is mounted onto the rear of the prevolume chamber (see illustration). 5 Ensure the ignition is switched off then disconnect the wiring connector from the valve. 6 Disconnect the vacuum pipes from the valve, noting their correct fitted locations, 4A 4A•24 Fuel and exhaust systems 17.11 Undo the retaining screws (arrowed) and remove the switchover valve assembly from its housing then undo the retaining screws and remove the valve from the engine compartment. 7 Refitting is the reverse of removal ensuring the vacuum hoses are correctly reconnected. Intake duct switchover valve housing 8 Slacken the retaining clip and disconnect the idle speed adjuster hose from the intake duct. 9 Slacken the retaining clips securing the intake ducts to the throttle housing and valve housing and remove both ducts from the engine compartment. 10 Disconnect the vacuum hose from the switchover valve diaphragm then slacken the lower retaining clips and remove the housing from the vehicle. 11 If necessary, slacken the retaining screws and remove the valve assembly from its housing, along with its sealing ring (see illustration). 12 Refitting is the reverse of removal ensuring all the intake ducts are securely reconnected. Manifold switchover valve solenoid valve 13 The manifold switchover valve solenoid valve is mounted onto the rear of the inlet manifold upper section on the left-hand side (see illustration). 17.19 Undo the retaining bolts (arrowed) and withdraw the switchover valve assembly from the manifold upper section 17.13 The manifold switchover valve solenoid valve (arrowed) is mounted onto the rear of the inlet manifold (shown with engine removed) 14 To gain access to the valve, remove the windscreen wiper arms and the water deflector panel from the base of the windscreen (see Chapter 12, Sections 15 and 16). 15 Ensure the ignition is switched off then disconnect the wiring connector from the valve. 16 Disconnect the vacuum pipes from the valve, noting their correct fitted locations, then undo the retaining screws and remove the valve from the manifold. 17 Refitting is the reverse of removal ensuring the vacuum hoses are correctly reconnected. Manifold switchover valve assembly 18 Remove the upper section of the inlet manifold as described in Section 15. 19 Disconnect the vacuum hose from the diaphragm unit then undo the retaining bolts and remove the valve assembly from the manifold ill (see illustration). Recover the sealing ring and discard it; a new one should be used on refitting. 20 On refitting fit a new sealing ring to the valve assembly then refit the valve to the manifold. Securely tighten the valve retaining bolts then refit the manifold upper section (see Section 15). 17.25 Removing the pre-volume chamber assembly 3510 Vauxhall/Opel Omega Pre-volume chamber assembly 21 Remove the airflow meter as described in Section 14. 22 Slacken the retaining clip and disconnect the idle speed adjuster hose from the intake duct. 23 Slacken the retaining clips securing the intake ducts to the throttle housing and switchover valve and remove both ducts from the engine compartment. 24 Disconnect the wiring connector and vacuum hose from the intake duct switchover valve solenoid valve on the rear of the chamber. 25 Unscrew the mounting nuts then free the chamber assembly from its lower mounting rubber and manoeuvre it out of position (see illustration). 26 Refitting is the reverse of removal ensuring the chamber is correctly engaged with its lower mounting rubber. 18 Exhaust system general information, removal and refitting 3 General information 1 On 2.0 litre engine models, the exhaust system consists of three sections: the front pipe which incorporates the catalytic converter, the intermediate pipe and centre silencer, and the tailpipe and main silencer box. 2 On 2.5 and 3.0 litre engine models the exhaust system consists of five sections; there is a separate front pipe (incorporating a catalytic converter) and intermediate pipe (incorporating a centre silencer) for each bank of cylinders with both exhaust sections being joined to a single tailpipe and main silencer. 3 The front pipe joints are flange joints which are secured by bolts and the tailpipe is secured to the intermediate pipe by a clamping ring. The system is suspended throughout its entire length by rubber mountings. Fuel and exhaust systems 4A•25 Removal Tailpipe 4 Each exhaust section can be removed individually, or alternatively, the complete system can be removed as a unit. Even if only one part of the system needs attention, it is often easier to remove the whole system and separate the sections on the bench. 5 To remove the system or part of the system, first jack up the front or rear of the car and support it securely on axle stands. Alternatively, position the car over an inspection pit or on car ramps. 12 Slacken the clamp(s) securing the tailpipe to the intermediate pipe(s) (as applicable) (see illustration). 13 Free the tailpipe from its mounting rubbers then disengage it from the intermediate pipe(s) and remove it from the underneath the vehicle. Front pipe 6 Trace the wiring back from the oxygen sensor, noting its correct routing, and disconnect its wiring connector (see illustration). Free the wiring from any clips so the sensor is free to be removed with the front pipe. 7 Slacken and remove the bolts securing the front pipe flange joint to the manifold. 8 Unscrew the bolt(s) securing the front pipe to its mounting bracket(s) (see illustration). 9 Slacken and remove the bolts securing the front pipe to the intermediate pipe and remove the front pipe from the vehicle (see illustration). Recover the gasket from the front pipe to manifold joint. Intermediate pipe 10 Slacken and remove the bolts securing the intermediate pipe to the front pipe. On 2.5 and 3.0 litre engines also remove the bolts securing the other intermediate pipe to its front pipe. 11 Slacken the clamp securing the pipe to the tailpipe then free the intermediate pipe from its mounting rubbers. Ease the intermediate pipe out from the tailpipe and remove it from underneath the vehicle. Complete system 14 Trace the wiring back from the oxygen sensor(s), noting its correct routing, and disconnect the wiring connector(s). Free the wiring from any clips so the sensor(s) is free to be removed with the front pipe. 15 Unscrew the bolts securing the front pipe(s) to the mounting bracket. 16 Slacken and remove the bolts securing the front pipe flange joint(s) to the manifold(s) and recover the gasket(s). 17 Free the exhaust system from all its mounting rubbers and lower it from underneath the vehicle. Heat shield(s) 18 The heat shields are secured to the underside of the body by various nuts and bolts. Each shield can be removed once the relevant exhaust section has been removed. If a shield is being removed to gain access to a component located behind it, it may prove sufficient in some cases to remove the retaining nuts and/or bolts, and simply lower the shield, without disturbing the exhaust system. Refitting 19 Each section is refitted by reversing the removal sequence, noting the following points: 18.6 The oxygen sensor wiring connector (arrowed) is clipped to the side of the transmission unit a) Ensure that all traces of corrosion have been removed from the flanges. b) Inspect the rubber mountings for signs of damage or deterioration, and renew as necessary. c) Always renew the front pipe manifold gasket whenever it is disturbed. d) Where no gasket is fitted to a joint, apply a smear of exhaust system jointing paste to ensure a gas-tight seal. e) Prior to refitting, lubricate the threads of the front pipe to manifold bolts with a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer). f) Prior to tightening the exhaust system fasteners to the specified torque, ensure that all rubber mountings are correctly located, and that there is adequate clearance between the exhaust system and vehicle underbody. 4A 18.8 Front pipe-to-mounting bracket bolts - 2.0 litre DOHC engine 18.9 Front pipe-to-intermediate pipe bolts - 2.0 litre DOHC engine 3510 Vauxhall/Opel Omega 18.12 Tailpipe-to-intermediate pipe clamp - 2.0 litre DOHC engine 4B•1 Chapter 4 Part B: Emission control systems Contents Catalytic converter - general information and precautions . . . . . . . . Emission control system testing - general information . . . . . . . . . . . Evaporative emission control system components - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exhaust emission control system components - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2 4 Exhaust gas recirculation (EGR) system components - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Secondary air injection system components - removal and refitting . 6 3 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications Torque wrench settings EGR valve bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EGR pipe union nuts - 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . EGR valve adaptor bolts - 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . Exhaust manifold shroud bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oxygen sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Roadwheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Secondary air injection system: Connecting pipe bolts: M6 bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M8 bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Non-return valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pump assembly: Pump/mounting rubber nuts/bolts . . . . . . . . . . . . . . . . . . . . . . . . . Mounting bracket-to-body nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . Air filter retaining clamp nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 General information 1 All UK models use unleaded petrol and also have various other features built into the fuel system to help minimise harmful emissions. All models are equipped with a crankcase emission-control system, a catalytic converter, an exhaust gas recirculation (EGR) system and an evaporative emission control system to keep fuel vapour/exhaust gas emissions down to a minimum. All models except those with a 2.0 litre SOHC engine are also fitted with the secondary air injection system to further improve the exhaust gas emissions during engine warm-up. Crankcase emission control 2 To reduce the emission of unburned hydrocarbons from the crankcase into the atmosphere, the engine is sealed and the blow-by gases and oil vapour are drawn from Nm 20 25 8 8 30 110 lbf ft 15 18 6 6 22 81 8 20 30 6 15 22 10 20 4 7 15 3 inside the crankcase, through a wire mesh oil separator, into the inlet tract to be burned by the engine during normal combustion. 3 Under conditions of high manifold depression (idling, deceleration) the gases will be sucked positively out of the crankcase. Under conditions of low manifold depression (acceleration, full-throttle running) the gases are forced out of the crankcase by the (relatively) higher crankcase pressure; if the engine is worn, the raised crankcase pressure (due to increased blow-by) will cause some of the flow to return under all manifold conditions. Exhaust emission control Note: All 2.5 and 3.0 litre engines have two catalytic converters and two oxygen sensors; one for each bank of cylinders. 4 To minimise the amount of pollutants which escape into the atmosphere, all models are fitted with a catalytic converter in the exhaust system. The system is of the closed-loop type, in which a oxygen sensor in the exhaust 3510 Vauxhall/Opel Omega system provides the engine management (fuel-injection/ignition) system ECU with constant feedback, enabling the ECU to adjust the mixture to provide the best possible conditions for the converter to operate. 5 The oxygen sensor’s tip is sensitive to oxygen and sends the ECU a varying voltage depending on the amount of oxygen in the exhaust gases; if the intake air/fuel mixture is too rich, the exhaust gases are low in oxygen so the sensor sends a low-voltage signal, the voltage rising as the mixture weakens and the amount of oxygen rises in the exhaust gases. Peak conversion efficiency of all major pollutants occurs if the intake air/fuel mixture is maintained at the chemically-correct ratio for the complete combustion of petrol of 14.7 parts (by weight) of air to 1 part of fuel (the stoichiometric ratio). The sensor output voltage alters in a large step at this point, the ECU using the signal change as a reference point and correcting the intake air/fuel mixture accordingly by altering the fuel injector pulse width. 4B 4B•2 Emission control systems alleviating the need to test all the system components individually, which is a timeconsuming operation that carries a risk of damaging the ECU. Evaporative emission control 6 To minimise the escape into the atmosphere of unburned hydrocarbons, an evaporative emissions control system is also fitted to all models. The fuel tank filler cap is sealed and a charcoal canister is mounted behind the right-hand front wing. The canister collects the petrol vapours generated in the tank when the car is parked and stores them until they can be cleared from the canister (under the control of the engine management system ECU) via the purge valve into the inlet tract to be burned by the engine during normal combustion. 7 To ensure that the engine runs correctly when it is cold and/or idling and to protect the catalytic converter from the effects of an overrich mixture, the purge control valve is not opened by the ECU until the engine has warmed up, and the engine is under load; the valve solenoid is then modulated on and off to allow the stored vapour to pass into the inlet tract. Exhaust gas recirculation (EGR) system 8 This system is designed to recirculate small quantities of exhaust gas into the inlet tract, and therefore into the combustion process. This process reduces the level of unburnt hydrocarbons present in the exhaust gas before it reaches the catalytic converter. The system is controlled by the Engine management (fuel-injection/ignition) ECU, using the information from its various sensors, via the EGR valve. 9 On 2.0 litre engines the EGR valve assembly contains the vacuum-operated valve and the electrical solenoid valve which is used to switch the valve on and off. On SOHC engines the valve is mounted onto the top of the inlet manifold and on DOHC engines it is mounted onto the rear of the cylinder head. 10 On 2.5 and 3.0 litre engines the EGR valve is an electrically-operated valve mounted on and adaptor situated on the right-hand side of the engine. Secondary air injection system 2.0 litre DOHC engine and all 2.5 and 3.0 litre engines 11 The purpose of the secondary air injection system is to decrease exhaust gas emissions when the engine is cold. The system achieves this by raising the temperature of the exhaust gases which has the effect of quickly warming the catalytic converter up to its normal operating temperature. Once the catalytic converter is up to temperature the air injection system is switched off. 12 The system consists of the pump, the air cut-off valve and the solenoid valve and is controlled by the engine management (fuelinjection/ignition) ECU. When the engine is cold, the solenoid valve switches the air valve to open and the pump injects a controlled amount of air into the cylinder head exhaust 3 Exhaust emission control system components removal and refitting 3 Note: All 2.5 and 3.0 litre engines have two catalytic converters and two oxygen sensors; one for each bank of cylinders. 3.3 Disconnect the wiring connector then unscrew the oxygen sensor (arrowed) from the front pipe (2.5 litre engine shown) ports. The air then mixes with the exhaust gases, causing any unburned particles of the fuel in the mixture to be burnt in the exhaust port/manifold which effectively raises the temperature of the exhaust gases. Once the catalytic converter is up to temperature, the solenoid valve closes the air valve and the pump is switched off. A non-return valve prevents the exhaust gases passing through the air valve. 2 Emission control system testing general information 1 If any of the emission control systems are thought to be faulty, first ensure that all the system wiring connectors are securely connected and free of corrosion. Ensure that the fault is not due to poor maintenance; ie, check that the air cleaner filter element is clean, the spark plugs are in good condition and correctly gapped, the cylinder compression pressures are correct, and that the engine breather hoses are clear and undamaged, referring to Chapters 1 and 2A, 2B or 2C for further information (as applicable). 2 If these checks fail to reveal the cause of the problem, the vehicle should be taken to a suitably-equipped Vauxhall dealer for testing. A wiring block connector is incorporated in the engine management circuit, into which a special electronic diagnostic tester can be plugged (see Chapter 4A, Section 6). The tester will locate the fault quickly and simply, Catalytic converter 1 The catalytic converter is an integral part of the exhaust system front pipe. Refer to Chapter 4A for removal and refitting details. Oxygen sensor Note: The oxygen sensor is delicate and will not work if it is dropped or knocked, if its power supply is disrupted, or if any cleaning materials are used on it. 2 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Disconnect the battery negative terminal. 3 Trace the wiring back from the oxygen sensor, which is screwed into the exhaust front pipe, to its connector which is clipped to the transmission unit. Disconnect the wiring connector and free the wiring from any relevant retaining clips or ties, noting its correct routing (see illustration). 4 Unscrew the sensor and remove it from the exhaust system front pipe (see illustration). Recover the sealing washer and discard it a new one should be used on refitting. 5 Refitting is a reverse of the removal procedure using a new sealing washer. Prior to installing the sensor apply a smear of high temperature grease to the sensor threads (Vauxhall recommend the use of special grease 19 48 602 - available from your Vauxhall dealer). Tighten the sensor to the specified torque and ensure that the wiring is correctly routed and in no danger of contacting either the exhaust system or engine. 4 Evaporative emission control system components removal and refitting 3 Charcoal canister 3.4 Oxygen sensor 2.0 litre DOHC engine 3510 Vauxhall/Opel Omega 1 The charcoal canister is located behind the right-hand front wing. To gain access to the canister, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Remove the right-hand front roadwheel. 2 Remove the retaining nuts and fasteners and remove the wheelarch liner to gain access to the canister. The fasteners are released by pressing out their centre pins and then prising Emission control systems 4B•3 4.2a Unscrew the retaining nuts then press out the centre pins . . . out the outer section; the centre pins must be recovered so they can be reused on refitting (see illustrations). 3 Slacken and remove the retaining nut and free the canister from its mounting. Mark the hoses for identification purposes then disconnect them and remove the canister from the vehicle (see illustrations). 4 Refitting is a reverse of the removal procedure ensuring the hoses are correctly and securely reconnected. Purge valve 2.0 litre SOHC engine 5 The purge valve is mounted onto the top of the inlet manifold. 6 Undo the bolts securing the wiring cover to the camshaft housing and position the cover clear of the purge valve. 7 To improve access to the valve, release the retaining clips and disconnect the breather hoses from the camshaft housing. 8 Ensure the ignition is switched off then depress the retaining clip and disconnect the wiring connector from the valve. 9 Slacken and remove the valve bracket upper screw then loosen the lower screw and free the valve bracket from the engine. Disconnect the hoses from the valve, noting their correct fitted locations and remove the valve from the engine. The valve and bracket can then be separated. 10 Refitting is a reversal of the removal procedure ensuring the hoses are securely connected. 4.3a Unscrew the retaining nut . . . 4.2b . . . and remove the fastener outer sections . . . 2.0 litre DOHC engine 11 The purge valve is mounted on the rear of the cylinder head, on the right-hand side of the DIS module. 12 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Access the valve can then be gained from above and underneath. 13 Ensure the ignition is switched off then disconnect the wiring connector from the valve. 14 Release the retaining clip and free the wiring harness from the purge valve bracket then undo the retaining screws and free the purge valve bracket from the cylinder head. 15 Disconnect the vacuum hoses, noting their correct fitted locations and remove the purge valve and mounting bracket from the vehicle. The valve and bracket can then be separated. 16 Refitting is a reversal of the removal procedure ensuring the hoses are securely connected. 4.2c . . . and remove the right-hand front wheelarch liner switched off, disconnect the wiring connector from the valve (see illustration). 20 Disconnect the vacuum hoses, noting their correct fitted locations and remove the purge valve and mounting bracket from the engine. The valve and bracket can then be separated. 21 Refitting is a reversal of the removal procedure ensuring the hoses are securely connected. 5 Exhaust gas recirculation (EGR) system components removal and refitting 3 EGR valve 2.0 litre SOHC engine 17 The purge valve is located at the rear of the right-hand cylinder head. 18 Remove the inlet manifold upper section as described in Chapter 4A. To further improve access, remove the windscreen wiper arms and the water deflector panel from the base of the windscreen (see Chapter 12, Sections 15 and 16). 19 Slacken and remove the valve bracket retaining bolt then, ensuring the ignition is 1 On 2.0 litre SOHC engines, to improve access undo the bolts securing the wiring cover to the camshaft housing and position the cover clear of the EGR valve which is mounted onto the top of the inlet manifold. 2 Ensure the ignition is switched off then disconnect the wiring connector and vacuum hose from the valve. 3 Undo the retaining screws and remove the valve and its gasket, noting which way around the valve is fitted. 4 Refitting is the reverse of removal using a new gasket. Ensure the valve is fitted the correct way around and tighten its retaining bolts to the specified torque. 4.3b . . . then free the charcoal canister from its mounting and disconnect it from its hoses 4.19 On 2.5 and 3.0 litre engines the purge valve (arrowed) is mounted on the rear of the right-hand cylinder head (shown with engine removed) 2.5 and 3.0 litre engines 3510 Vauxhall/Opel Omega 4B 4B•4 Emission control systems 5.7 On 2.5 and 3.0 litre engines, disconnect the wiring connector . . . 2.0 litre DOHC engine 5 The valve is mounted on the rear of the cylinder head. Removal and refitting is as described in paragraphs 2 to 4. 2.5 and 3.0 litre engine 6 The valve is mounted onto an adaptor on the right-hand cylinder head. 7 Ensure the ignition is switched off then disconnect the wiring connector from the valve (see illustration). 8 Undo the retaining screws and remove the valve and its gasket, noting which way around the valve is fitted (see illustration). 9 Refitting is the reverse of removal using a new gasket. Ensure the valve is fitted the correct way around and tighten its retaining bolts to the specified torque. EGR valve pipe 2.5 and 3.0 litre engines 10 Slacken the union nuts and remove the pipe connecting the valve adaptor to the righthand cylinder bank exhaust manifold (see illustrations). 11 On refitting, lubricate the threads of the union nuts with a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer) and tighten them to the specified torque. EGR valve adaptor 2.5 and 3.0 litre engines 12 Remove the EGR valve and pipe as described earlier in this Section. 6.4a Disconnect the wiring connector . . . 5.8 . . . then undo the retaining bolts (arrowed) and remove the EGR valve from its adaptor 5.10a Unscrew the union nuts . . . 13 Unclip the accelerator cable from its mounting bracket then unbolt and remove the mounting bracket. 14 Unbolt the bracket from the end of the adaptor then slacken then remove the retaining bolts and remove the adaptor and gasket from the inlet manifold. 15 Refitting is the reverse of removal using a new gasket. Tighten the retaining bolts to the specified torque then refit the EGR valve and pipe (see paragraphs 9 and 11). 6 Secondary air injection system components removal and refitting 3 Note: This system is not fitted to 2.0 litre SOHC engines. 2.0 litre DOHC engine Pump and filter assembly Note: The filter can be renewed without removing the pump assembly from the vehicle. Detach the hose from the filter then unscrew the nut and remove the retaining clamp and filter from the bracket. 1 The pump and filter assembly is located behind the left-hand front wing. To gain access to the canister, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Remove the left-hand front roadwheel. 2 Remove the retaining nuts and fasteners 6.4b . . . then release the retaining clip and disconnect the hose from the air pump 3510 Vauxhall/Opel Omega 5.10b . . . and remove the EGR valve pipe from the engine and remove the wheelarch liner to gain access to the canister. The fasteners are released by pressing out their centre pins and then prising out the outer section; the centre pins must be recovered so they can be reused on refitting. 3 Unbolt the horn assembly from the pump mounting bracket and position it clear. 4 Disconnect the pump wiring connector then slacken the retaining clip and disconnect the air hose from the pump (see illustrations). 5 Slacken and remove the pump mounting bracket retaining nuts then manoeuvre the assembly out from underneath the vehicle (see illustration). 6 To separate the pump and bracket first slacken the retaining clips and disconnect the hose connecting the pump to its air filter. If necessary, undo the nut then remove the retaining clamp and air filter from the bracket (see illustration). 6.5 Undo the retaining nuts (arrowed) and remove the pump and filter assembly from the vehicle Emission control systems 4B•5 6.8a Undo the retaining bolts (arrowed) . . . 6.6 Release the retaining clip (A) and disconnect the hose then undo the retaining nut (B) and remove the clamp and filter assembly Cut-off valve 6.8b . . . and separate the pump from its mounting bracket 6.8c If necessary, undo the retaining nuts (arrowed) and remove the mounting plate and rubber from the bracket 7 Make alignment marks between the pump, bracket, mounting plate and rubber then free the pump wiring connector from the bracket. 8 Undo the retaining bolts and remove the pump from its mounting bracket. If necessary, unscrew the retaining nuts and remove the mounting plate and rubber from the bracket (see illustrations). 9 Refitting is the reverse of removal aligning the marks made prior to removal and tighten the mounting nuts and bolts to their specified torque settings. 6.10 On 2.0 litre DOHC engines disconnect the vacuum hose (1) then release the retaining clips and free the air hoses (2) from the cut-off valve 10 The valve is located on the left-hand side of the engine compartment. Disconnect the vacuum pipe from the valve then release the retaining clips and disconnect the air hoses (see illustration). 11 Slacken and remove the retaining bolts and remove the valve from the vehicle, noting which way around it is fitted. 12 Refitting is the reverse of removal making sure the valve is fitted the correct way around; the arrow on the valve must point in the direction of air flow (towards the engine). Cut-off valve solenoid 13 The solenoid valve is located next to the cut-off valve on the left-hand side of the engine compartment (see illustration). 14 Ensure the ignition is switched off then disconnect the wiring connector from the valve and detach the vacuum hoses, noting each ones correct fitted location. 6.13 Disconnect the wiring connector (1) and vacuum hoses (2) from the cut-off valve solenoid 3510 Vauxhall/Opel Omega 4B 4B•6 Emission control systems 6.18 Release the retaining clip and disconnect the air hose from the nonreturn valve (arrowed) 6.28a Disconnect the vacuum pipe from the solenoid valve . . . 6.28b . . . then release the retaining clips and disconnect the hoses from the cut-off valve 15 Undo the retaining screws and remove the valve from the engine compartment. 16 Refitting is the reverse of removal ensuring the vacuum hoses are correctly reconnected. the breather hose from the left-hand side of the cylinder head cover. 24 Undo the retaining bolts and remove the connecting pipe from the cylinder head/ manifold. Recover the gaskets which are fitted between the pipe unions and cylinder head and discard them. 25 Refitting is the reverse of removal, noting the following. a) Ensure the mating surfaces are clean and dry and use new gaskets. b) Apply a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer) to the threads of the pipe retaining bolts and heatshield bolts prior to refitting. c) Tighten all bolts to their specified torque settings (where given). solenoid valve then release the retaining clips and disconnect the air hoses from the cut-off valve (see illustrations). 29 Slacken and remove the retaining bolts securing the valve mounting bracket to the radiator and remove the bracket assembly from the vehicle, disconnecting the valve wiring connector as it becomes accessible (see illustration). 30 Undo the retaining bolts and remove the cut-off valve/solenoid valve (as applicable) from the bracket, noting which way around it is fitted (see illustration). 31 Refitting is the reverse of removal. If the cut-off valve has been removed, make sure it is fitted the correct way around with the arrow pointing in the direction of air flow (towards the engine). 2.5 and 3.0 litre engines 32 The non-return valve is screwed onto the left-hand end of the front connecting pipe and is located just in front of the timing belt cover (see illustration). To improve access to the valve unbolt the air conditioning pipe/hose bracket from the cylinder head and position the hose/pipe to one side. 33 Release the retaining clip and disconnect the air hose from the pipe then unscrew the valve and remove it from its pipe. Non-return valve 17 The non-return valve is located on the top of the exhaust manifold. 18 Release the retaining clip and disconnect the air hose from the pipe then unscrew the valve and remove it from the connecting pipe (see illustration). 19 On refitting, clean the valve threads and apply a smear of fresh sealing compound to them (Vauxhall recommend the use of sealing compound 15 03 295 - available from your Vauxhall dealer). Refit the valve to its pipe and tighten it to the specified torque before securely reconnecting the air hose. Connecting pipe 20 Release the retaining clip and disconnect the air hose from the connecting pipe nonreturn valve. 21 Slacken and remove the retaining bolts and remove the bracket securing the connecting pipe to the exhaust manifold. 22 Undo the retaining bolts and remove the heatshield from the exhaust manifold. 23 Slacken the retaining clip and disconnect Pump and filter assembly 26 Refer to paragraphs 1 to 9. Cut-off valve and solenoid valve 27 The cut-off valve and its solenoid are mounted onto a bracket which is secured to the rear of the radiator. 28 Disconnect the vacuum pipe from the 6.29 Undo the retaining bolts and disconnect the wiring connector (arrowed) then remove the bracket assembly from the vehicle Non-return valve 6.30 Air cut-off valve (A) and solenoid valve (B) can then be unbolted from the bracket 3510 Vauxhall/Opel Omega Emission control systems 4B•7 6.32 Non return valve location 2.5 and 3.0 litre engines 6.36 Disconnect the air hose from the nonreturn valve on the front connecting pipe 6.37b . . . and right-hand retaining nuts then (if necessary) slacken the alternator mounting nut and pivot the bracket (arrowed) clear of the pipe . . . 34 On refitting, clean the valve threads and apply a smear of fresh sealing compound to them (Vauxhall recommend the use of sealing compound 15 03 295 - available from your Vauxhall dealer). Refit the valve to its pipe and tighten it to the specified torque before securely reconnecting the air hose. Front connecting pipe 35 Remove the multi-ram air intake system prevolume chamber as described in Chapter 4A. 36 Release the retaining clip and disconnect the air hose from the front connecting pipe non-return valve (see illustration). 37 Unscrew the pipe retaining nuts then release the retaining clips securing the pipe ends to the hoses and remove the assembly from the engine compartment. If necessary, slacken the alternator upper mounting nut and pivot the pipe bracket out of position to gain the necessary clearance required for removal (see illustrations). 38 Refitting is the reverse of removal ensuring the hose are correctly and securely reconnected. 6.37a Slacken and remove the left-hand . . . 6.37c . . . to allow the front connecting pipe to be removed from the engine 41 Slacken and remove the bolts securing the upper and lower heatshields to the lefthand exhaust manifold. Remove the lower heatshield and position the upper one clear of the manifold so access can be gained to the connecting pipe bolts. 42 Slacken and remove the retaining bolts and free the connecting pipe from the manifold (see illustration). Release the retaining clip securing the rubber hose to the front of the connecting pipe then disconnect the pipe and manoeuvre it out from underneath the vehicle. Recover the gaskets which are fitted between the pipe and manifold and discard them. 43 Refitting is the reverse of removal, noting the following points. a) Ensure the mating surfaces are clean and dry and use new gaskets (see illustration). 6.42 Removing the left-hand connecting pipe from the manifold (shown with engine removed) 6.43 On refitting, ensure the mating surfaces are clean and dry and fit new gaskets to the connecting pipe the auxiliary drivebelt then unbolt the compressor and position it clear of its mounting bracket (see Chapters 1 and 3). Warning: Do not disconnect any of the refrigerant pipes/hoses Left-hand cylinder head connecting pipe 39 Remove the exhaust system left-hand front pipe as described in Chapter 4A. 40 On models with air conditioning, remove 3510 Vauxhall/Opel Omega 4B 4B•8 Emission control systems 6.45a Undo the retaining bolts and remove the lower . . . 6.45b . . . and upper heatshields from the right-hand exhaust manifold (shown with engine removed) 6.47 Removing the right-hand connecting pipe from the manifold b) Apply a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer) to the threads of the pipe retaining bolts and the heatshield bolts prior to refitting. c) Tighten all bolts to their specified torque settings (where given). dry and use new gaskets. b) Apply a smear of high-temperature grease (Vauxhall recommend the use of assembly paste 19 48 569 - available from your Vauxhall dealer) to the threads of the pipe retaining bolts and heatshield bolts prior to refitting. c) Tighten all bolts to their specified torque settings (where given). d) DO NOT push- or tow-start the car - this will soak the catalytic converter in unburned fuel, causing it to overheat when the engine does start. e) DO NOT switch off the ignition at high engine speeds. f) DO NOT use fuel or engine oil additives these may contain substances harmful to the catalytic converter. g) DO NOT continue to use the car if the engine burns oil to the extent of leaving a visible trail of blue smoke. h) Remember that the catalytic converter operates at very high temperatures. DO NOT, therefore, park the car in dry undergrowth, over long grass or piles of dead leaves after a long run. i) Remember that the catalytic converter is FRAGILE - do not strike it with tools during servicing work. j) In some cases a sulphurous smell (like that of rotten eggs) may be noticed from the exhaust. This is common to many catalytic converter-equipped cars and once the car has covered a few thousand miles the problem should disappear. k) The catalytic converter, used on a wellmaintained and well-driven car, should last indefinitely - if the converter is no longer effective it must be renewed. Right-hand cylinder head connecting pipe 44 Slacken and remove the bolt securing the coolant pipe bracket to the right-hand cylinder head. 45 Slacken and remove the retaining bolts then remove the lower and upper heatshields from the exhaust manifold (see illustrations). 46 Taking care not to place excess strain on the coolant pipe, slacken and remove the retaining bolts securing the connecting pipe to the manifold. 47 Free the connecting pipe from the manifold then release the retaining clip securing the rubber hose to the front of the connecting pipe then disconnect the pipe and manoeuvre it out of position (see illustration). Recover the gaskets which are fitted between the pipe and manifold and discard them. 48 Refitting is the reverse of removal, noting the following points. a) Ensure the mating surfaces are clean and 7 Catalytic converter general information and precautions 1 The catalytic converter is a reliable and simple device which needs no maintenance in itself, but there are some facts of which an owner should be aware if the converter is to function properly for its full service life. a) DO NOT use leaded petrol in a car equipped with a catalytic converter - the lead will coat the precious metals, reducing their converting efficiency and will eventually destroy the converter. b) Always keep the ignition and fuel systems well-maintained in accordance with the manufacturer’s schedule. c) If the engine develops a misfire, do not drive the car at all (or at least as little as possible) until the fault is cured. 3510 Vauxhall/Opel Omega 5A•1 Chapter 5 Part A: Starting and charging systems Contents Alternator - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Alternator - testing and overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Alternator drivebelt - removal, refitting and tensioning . . . . . . . . . . . 6 Battery - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Battery - testing and charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Battery check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See Weekly checks Charging system - testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Electrical fault finding - general information . . . . . . . . . . . . . . . . . . . 2 General information and precautions . . . . . . . . . . . . . . . . . . . . . . . . 1 Ignition switch - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 12 Oil level sensor - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 14 Oil pressure warning light switch - removal and refitting . . . . . . . . . 13 Starter motor - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 10 Starter motor - testing and overhaul . . . . . . . . . . . . . . . . . . . . . . . . . 11 Starting system - testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications System type ........................................... 12-volt, negative earth 5A Battery Charge condition: Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Normal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.5 volts 12.6 volts 12.7 volts Torque wrench settings Nm lbf ft 35 26 18 20 35 8 40 13 15 26 6 30 45 25 60 40 33 18 44 30 Alternator mounting bolts: 2.0 litre engine: Lower bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Upper bracket bolts: SOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DOHC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil level sensor bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil pressure switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Starter motor bolts: 2.0 litre engine: Lower bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear mounting bracket to block bolt . . . . . . . . . . . . . . . . . . . . . . . Upper bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3510 Vauxhall/Opel Omega 5A•2 Starting and charging systems 1 General information and precautions General information 1 The engine electrical system consists mainly of the charging and starting systems. Because of their engine-related functions, these components are covered separately from the body electrical devices such as the lights, instruments, etc (which are covered in Chapter 12). Refer to Part B for information on the ignition system. 2 The electrical system is of the 12-volt negative earth type. 3 The battery is of the low maintenance or maintenance-free (sealed for life) type and is charged by the alternator, which is belt-driven from the crankshaft pulley. 4 The starter motor is of the pre-engaged type incorporating an integral solenoid. On starting, the solenoid moves the drive pinion into engagement with the flywheel ring gear before the starter motor is energised. Once the engine has started, a one-way clutch prevents the motor armature being driven by the engine until the pinion disengages from the flywheel. Precautions 5 Further details of the various systems are given in the relevant Sections of this Chapter. While some repair procedures are given, the usual course of action is to renew the component concerned. The owner whose interest extends beyond mere component renewal should obtain a copy of the Automobile Electrical & Electronic Systems Manual, available from the publishers of this manual. 6 It is necessary to take extra care when working on the electrical system to avoid damage to semi-conductor devices (diodes and transistors), and to avoid the risk of personal injury. In addition to the precautions given in Safety first! at the beginning of this manual, observe the following when working on the system: 7 Always remove rings, watches, etc before working on the electrical system. Even with the battery disconnected, capacitive discharge could occur if a component’s live terminal is earthed through a metal object. This could cause a shock or nasty burn. 8 Do not reverse the battery connections. Components such as the alternator, electronic control units, or any other components having semi-conductor circuitry could be irreparably damaged. 9 If the engine is being started using jump leads and a slave battery, connect the batteries positive-to-positive and negative-tonegative (see Jump starting). This also applies when connecting a battery charger. 10 Never disconnect the battery terminals, the alternator, any electrical wiring or any test instruments when the engine is running. 11 Do not allow the engine to turn the alternator when the alternator is not connected. 12 Never test for alternator output by flashing the output lead to earth. 13 Never use an ohmmeter of the type incorporating a hand-cranked generator for circuit or continuity testing. 14 Always ensure that the battery negative lead is disconnected before carrying out any serious work on the electrical system. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 15 Before using electric-arc welding equipment on the car, disconnect the battery, alternator and components such as the engine management electronic control unit to protect them from the risk of damage. 16 The radio/cassette unit fitted as standard equipment by Vauxhall is equipped with a builtin security code to deter thieves. If the power source to the unit is cut, the anti-theft system will activate. Even if the power source is immediately reconnected, the radio/ cassette unit will not function until the correct security code has been entered. Therefore, if you do not know the correct security code for the radio/ cassette unit do not disconnect the battery negative terminal of the battery or remove the radio/cassette unit from the vehicle. Refer to Radio/cassette unit anti-theft system precaution Section for further information. 2 Electrical fault finding general information Refer to Chapter 12. 3 Battery testing and charging 1 Standard and low maintenance battery - testing 1 If the vehicle covers a small annual mileage, 3.5 Standard Vauxhall battery with built-in charge indicator (arrowed) 3510 Vauxhall/Opel Omega it is worthwhile checking the specific gravity of the electrolyte every three months to determine the state of charge of the battery. Use a hydrometer to make the check and compare the results with the following table. Note that the specific gravity readings assume an electrolyte temperature of 15ºC (60ºF); for every 10ºC (18ºF) below 15ºC (60ºF) subtract 0.007. For every 10ºC (18ºF) above 15ºC (60ºF) add 0.007. Ambient temperature - 25ºC (77ºF) Above Below Charged 1.210 to 1.230 1.270 to 1.290 70% charged 1.170 to 1.190 1.230 to 1.250 Discharged 1.050 to 1.070 1.110 to 1.130 2 If the battery condition is suspect, first check the specific gravity of electrolyte in each cell. A variation of 0.040 or more between any cells indicates loss of electrolyte or deterioration of the internal plates. 3 If the specific gravity variation is 0.040 or more, the battery should be renewed. If the cell variation is satisfactory but the battery is discharged, it should be charged as described later in this Section. Maintenance-free battery testing 4 In cases where a sealed for life maintenance-free battery is fitted, topping-up and testing of the electrolyte in each cell is not possible. The condition of the battery can therefore only be tested using a battery condition indicator or a voltmeter. 5 Certain models may be fitted with a Delco or Vauxhall type maintenance-free battery, with a built-in charge condition indicator (see illustration). The indicator is located in the top of the battery casing, and indicates the condition of the battery from its colour. If the indicator shows green, then the battery is in a good state of charge. If the indicator turns darker, eventually to black, then the battery requires charging, as described later in this Section. If the indicator shows clear/yellow, then the electrolyte level in the battery is too low to allow further use, and the battery should be renewed. Do not attempt to charge, load or jump start a battery when the indicator shows clear/yellow. 6 If testing the battery using a voltmeter, connect the voltmeter across the battery and compare the result with those given in the Specifications under charge condition. The test is only accurate if the battery has not been subjected to any kind of charge for the previous six hours. If this is not the case, switch on the headlights for 30 seconds, then wait four to five minutes before testing the battery after switching off the headlights. All other electrical circuits must be switched off, so check that the doors and tailgate are fully shut when making the test. 7 If the voltage reading is less than 12.2 volts, then the battery is discharged, whilst a reading of 12.2 to 12.4 volts indicates a partially discharged condition. Starting and charging systems 5A•3 8 If the battery is to be charged, remove it from the vehicle (Section 4) and charge it as described later in this Section. Standard and low maintenance battery - charging Note: The following is intended as a guide only. Always refer to the manufacturer’s recommendations (often printed on a label attached to the battery) before charging a battery. 9 Charge the battery at a rate of 3.5 to 4 amps and continue to charge the battery at this rate until no further rise in specific gravity is noted over a four hour period. 10 Alternatively, a trickle charger charging at the rate of 1.5 amps can safely be used overnight. 11 Specially rapid boost charges which are claimed to restore the power of the battery in 1 to 2 hours are not recommended, as they can cause serious damage to the battery plates through overheating. 12 While charging the battery, note that the temperature of the electrolyte should never exceed 37.8ºC (100ºF). Maintenance-free battery charging Note: The following is intended as a guide only. Always refer to the manufacturer’s recommendations (often printed on a label attached to the battery) before charging a battery. 13 This battery type takes considerably longer to fully recharge than the standard type, the time taken being dependent on the extent of discharge, but it can take anything up to three days. 14 A constant voltage type charger is required, to be set, when connected, to 13.9 to 14.9 volts with a charger current below 25 amps. Using this method, the battery should be usable within three hours, giving a voltage reading of 12.5 volts, but this is for a partially discharged battery and, as mentioned, full charging can take considerably longer. 15 If the battery is to be charged from a fully discharged state (condition reading less than 12.2 volts), have it recharged by your Vauxhall dealer or local automotive electrician, as the charge rate is higher and constant supervision during charging is necessary. 4 Battery removal and refitting 4.3 Where necessary, unclip the fusible link housing from the relay box and position it clear of the battery 2 Unclip the cover (where fitted) then slacken the clamp nut and disconnect the clamp from the battery negative (earth) terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 3 On models where a fusible link housing is clipped onto the engine compartment relay box, unclip the housing and position it clear of the battery (see illustration). 4 Lift the insulation cover and disconnect the positive terminal lead in the same way. 5 Unscrew the bolt and remove the battery retaining clamp and lift the battery out of the engine compartment. Refitting 6 Refitting is a reversal of removal, but smear petroleum jelly on the terminals when reconnecting the leads, and always reconnect the positive lead first, and the negative lead last. 5 Charging system testing 2 Note: Refer to the warnings given in Safety first! and in Section 1 of this Chapter before starting work. 1 If the ignition warning light fails to illuminate when the ignition is switched on, first check 6 Alternator drivebelt removal, refitting and tensioning 1 Refer to the procedure given for the auxiliary drivebelt in Chapter 1. 7 Alternator removal and refitting 1 3 Removal 1 Disconnect the battery negative lead and proceed as described under the relevant subheading. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. Note: If a Vauxhall radio/cassette unit is fitted, refer to Radio/cassette unit anti-theft system precaution. Removal 1 The battery is located on the left-hand side of the engine compartment. On some models the battery will be housed in a protective casing. the alternator wiring connections for security. If satisfactory, check that the warning light bulb has not blown, and that the bulbholder is secure in its location in the instrument panel. If the light still fails to illuminate, check the continuity of the warning light feed wire from the alternator to the bulbholder. If all is satisfactory, the alternator is at fault and should be renewed or taken to an autoelectrician for testing and repair. 2 If the ignition warning light illuminates when the engine is running, stop the engine and check that the drivebelt is correctly tensioned (see Section 6) and that the alternator connections are secure. If all is so far satisfactory, have the alternator checked by an auto-electrician for testing and repair. 3 If the alternator output is suspect even though the warning light functions correctly, the regulated voltage may be checked as follows. 4 Connect a voltmeter across the battery terminals and start the engine. 5 Increase the engine speed until the voltmeter reading remains steady; the reading should be approximately 12 to 13 volts, and no more than 14 volts. 6 Switch on as many electrical accessories (eg, the headlights, heated rear window and heater blower) as possible, and check that the alternator maintains the regulated voltage at around 13 to 14 volts. 7 If the regulated voltage is not as stated, the fault may be due to worn brushes, weak brush springs, a faulty voltage regulator, a faulty diode, a severed phase winding or worn or damaged slip rings. The alternator should be renewed or taken to an auto-electrician for testing and repair. 2.0 litre engine 7.2 On 2.0 litre DOHC engines, disconnect the wiring connector from the intake air temperature sensor and airflow meter . . . 3510 Vauxhall/Opel Omega 2 Disconnect the wiring connectors from the intake air temperature sensor and the airflow meter (see illustration). 5A 5A•4 Starting and charging systems 7.3a . . . then disconnect the breather hose from the camshaft cover . . . 3 Slacken the retaining clips then disconnect the intake duct from the air cleaner and throttle housing and remove the duct assembly from the engine compartment. On DOHC engines it will be necessary to disconnect the breather hose in order to allow the duct to be removed (see illustrations). 4 Release the auxiliary drivebelt as described in Chapter 1 and disengage it from the alternator pulley. 5 Undo the bolts and remove the support brackets securing the alternator to the inlet manifold and cylinder head. Slacken the lower mounting bolt and pivot the alternator away from the block to improve access to the wiring connections. 6 Remove the rubber covers (where fitted) from the alternator terminals, then unscrew the retaining nuts and disconnect the wiring from the rear of the alternator. 7 Unscrew the nut from the lower mounting bolt then withdraw the bolt and manoeuvre the alternator out of position. 2.5 and 3.0 litre engines 8 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Undo the retaining screws and remove the undercover from beneath the engine so access to the alternator can be gained from below. 9 Release the auxiliary drivebelt as described in Chapter 1 and disengage it from the alternator pulley. 10 Remove the rubber covers (where fitted) from the alternator terminals, then unscrew the retaining nuts and disconnect the wiring from the rear of the alternator (see illustration). 11 Slacken and remove the upper and lower mounting nut and bolt then manoeuvre the alternator out of position. Refitting 12 Refitting is the reverse of removal tightening all mounting bolts to their specified torque settings (where given). Ensure the 7.3b . . . before slackening the retaining clips and removing the intake duct assembly drivebelt is correctly refitted and tensioned as described in Chapter 1. 8 Alternator testing and overhaul 5 1 If the alternator is thought to be suspect, it should be removed from the vehicle and taken to an auto-electrician for testing. Most autoelectricians will be able to supply and fit brushes at a reasonable cost. However, check on the cost of repairs before proceeding as it may prove more economical to obtain a new or exchange alternator. 9 Starting system testing 3 Note: Refer to the precautions given in Safety first! and in Section 1 of this Chapter before starting work. 1 If the starter motor fails to operate when the ignition key is turned to the appropriate position, the following possible causes may be to blame. 7.10 Slacken the retaining nuts (arrowed) and disconnect the wiring from the rear of the alternator (shown with engine removed) 3510 Vauxhall/Opel Omega a) The battery is faulty. b) The electrical connections between the switch, solenoid, battery and starter motor are somewhere failing to pass the necessary current from the battery through the starter to earth. c) The solenoid is faulty. d) The starter motor is mechanically or electrically defective. 2 To check the battery, switch on the headlights. If they dim after a few seconds, this indicates that the battery is discharged recharge (see Section 3) or renew the battery. If the headlights glow brightly, operate the ignition switch and observe the lights. If they dim, then this indicates that current is reaching the starter motor, therefore the fault must lie in the starter motor. If the lights continue to glow brightly (and no clicking sound can be heard from the starter motor solenoid), this indicates that there is a fault in the circuit or solenoid - see following paragraphs. If the starter motor turns slowly when operated, but the battery is in good condition, then this indicates that either the starter motor is faulty, or there is considerable resistance somewhere in the circuit. 3 If a fault in the circuit is suspected, disconnect the battery leads (including the earth connection to the body), the starter/solenoid wiring and the engine/transmission earth strap. Thoroughly clean the connections, and reconnect the leads and wiring, then use a voltmeter or test lamp to check that full battery voltage is available at the battery positive lead connection to the solenoid, and that the earth is sound. Smear petroleum jelly around the battery terminals to prevent corrosion corroded connections are amongst the most frequent causes of electrical system faults. 4 If the battery and all connections are in good condition, check the circuit by disconnecting the wire from the solenoid blade terminal. Connect a voltmeter or test lamp between the wire end and a good earth Starting and charging systems 5A•5 (such as the battery negative terminal), and check that the wire is live when the ignition switch is turned to the start position. If it is, then the circuit is sound - if not the circuit wiring can be checked as described in Chapter 12, Section 2. 5 The solenoid contacts can be checked by connecting a voltmeter or test lamp between the battery positive feed connection on the starter side of the solenoid, and earth. When the ignition switch is turned to the start position, there should be a reading or lighted bulb, as applicable. If there is no reading or lighted bulb, the solenoid is faulty and should be renewed. 6 If the circuit and solenoid are proved sound, the fault must lie in the starter motor. In this event, it may be possible to have the starter motor overhauled by a specialist, but check on the cost of spares before proceeding, as it may prove more economical to obtain a new or exchange motor. 10 Starter motor removal and refitting 4 Removal 1 Disconnect the battery negative lead then firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Undo the retaining screws and remove the undercover from beneath the engine then proceed as described under the relevant sub-heading. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2.0 litre engine 2 Slacken and remove the two retaining nuts and disconnect the wiring from the starter motor solenoid. Recover the washers under the nuts. On DOHC engine models, to improve access to the motor, undo the retaining bolts and remove the inlet manifold support bracket. 3 Unscrew the retaining bolt securing the starter motor rear bracket to the cylinder block. 4 Slacken and remove the upper and lower retaining bolts, noting the bolts are different lengths, and remove the starter motor from the vehicle. The upper bolt comes through from behind and secures the transmission unit to the cylinder block. 2.5 and 3.0 litre engine 5 Remove the right-hand engine mounting and bracket as described in Chapter 2C. 6 Slacken and remove the two retaining nuts and disconnect the wiring from the starter motor solenoid. Recover the washers under the nuts. 7 Slacken and remove the upper and lower retaining bolts and remove the starter motor from the vehicle. Refitting 8 Refitting is a reversal of removal tightening the retaining bolts to the specified torque. Ensure all wiring is correctly routed and its retaining nuts are securely tightened. 14 Oil level sensor removal and refitting 3 2.0 litre SOHC engine 11 Starter motor testing and overhaul 5 1 If the starter motor is thought to be suspect, it should be removed from the vehicle and taken to an auto-electrician for testing. Most auto-electricians will be able to supply and fit brushes at a reasonable cost. However, check on the cost of repairs before proceeding as it may prove more economical to obtain a new or exchange motor. 12 Ignition switch removal and refitting 1 The ignition switch is integral with the steering column lock, and can be removed as described in Chapter 10. 13 Oil pressure warning light switch removal and refitting 2 Removal 1 The switch is screwed into the oil pump housing which is located on the front of the engine, on the end of the crankshaft. On 2.0 litre engines the switched is screwed into the rear of the housing and on 2.5 and 3.0 litre engines it is screwed into the front of the housing. 2 To improve access to the switch, firmly apply the handbrake then jacked up the front of the vehicle and support it on axle stands. Undo the retaining bolts and remove the undercover from beneath the engine unit. 3 Disconnect the wiring connector then unscrew the switch and recover the sealing washer. Be prepared for oil spillage, and if the switch is to be left removed from the engine for any length of time, plug the switch aperture. Removal 1 The oil level sensor (where fitted) is located on the right-hand face of the engine sump. 2 To gain access to the sensor, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. Where necessary, undo the retaining screws and remove the undercover from beneath the engine unit. 3 Drain the engine oil into a clean container then refit the drain plug and tighten it to the specified torque setting (see Chapter 1). 4 Disconnect the wiring connector from the sensor. 5 Unscrew the retaining bolts then ease the sensor out from the sump and remove it along with its sealing ring. Discard the sealing ring, a new one should be used on refitting. Refitting 6 Refitting is the reverse of removal using a new sealing ring. On completion refill the engine with oil (see Chapter 1). 2.0 litre DOHC engine Engines with a one-piece sump 7 Remove and refit the sensor as described in paragraphs 1 to 6. Engines with a two-piece sump 8 Remove and refit the sensor as described in paragraphs 9 to 11. 2.5 and 3.0 litre engine Removal 9 Remove the sump pan as described in Chapter 2C. 10 Unscrew the retaining bolts and remove the sensor from the sump pan, noting which way around it is fitted (see illustration). Refitting 11 Ensure the sensor is correctly positioned then tighten its retaining bolts to the specified torque. Refit the sump pan as described in Chapter 2C. Refitting 4 Examine the sealing washer for signs of damage or deterioration and if necessary renew. 5 Refit the switch and washer, tightening it to the specified torque, and reconnect the wiring connector. 6 Refit the undercover then lower the vehicle to the ground. Check and, if necessary, top up the engine oil as described in Weekly checks. 3510 Vauxhall/Opel Omega 14.10 Removing the oil level sensor (2.5 litre engine shown) 5A 5B•1 Chapter 5 Part B: Ignition system Contents DIS module - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Ignition system - general information . . . . . . . . . . . . . . . . . . . . . . . . 1 Ignition system - testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Ignition timing - checking and adjustment . . . . . . . . . . . . . . . . . . . . 4 Spark plug renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See Chapter 1 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications System type ........................................... Distributorless ignition system controlled by engine management ECU 2.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 and 3.0 litre engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3-4-2 (No 1 cylinder at timing belt end) 1-2-3-4-5-6 (No1 cylinder at timing belt end of right-hand cylinder bank) Torque wrench settings Nm 8 15 Firing order DIS module bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DIS module bracket bolts - 2.0 litre SOHC engine . . . . . . . . . . . . . . . . . 1 Ignition system general information Warning: Voltages produced by an electronic ignition system are considerably higher than those produced by conventional ignition systems. Extreme care must be taken when working on the system with the ignition switched on. Persons with surgically-implanted cardiac pacemaker devices should keep well clear of the ignition circuits, components and test equipment. 2.0 litre engine 1 The ignition system is integrated with the fuel injection system to form a combined engine management system under the control of one ECU (See Chapter 4A, Section 13 for further information). The ignition side of the system is of the distributorless type, and consists of the DIS (distributorless ignition system) module and the knock sensor. 2 The DIS module is actually a four output ignition coil. The module actually consists of two separate HT coils which supply two cylinders each (one coil supplies cylinders 1 and 4, and the other cylinders 2 and 3). Under the control of the ECU, the module operates on the wasted spark principle, ie. each spark plug sparks twice for every cycle of the engine, once on the compression stroke and once on the exhaust stroke. The ECU uses its lbf ft 6 11 inputs from the various sensors to calculate the required ignition advance setting and coil charging time. 3 The knock sensor is mounted onto the cylinder block and informs the ECU when the engine is pinking under load. The sensor is sensitive to vibration and detects the knocking which occurs when the engine starts to pink (pre-ignite). The knock sensor sends an electrical signal to the ECU which in turn retards the ignition advance setting until the pinking ceases. 2.5 and 3.0 litre engine 4 Refer to the information given in paragraphs 1 to 3 noting that there are two knock sensors (one for the left-hand bank of cylinders and one for the right-hand bank) and the DIS module is a six output coil consisting of three separate HT coils which supply two cylinders each. 2 Ignition system testing 5 1 If a fault appears in the engine management (fuel injection/ignition) system first ensure that the fault is not due to a poor electrical connection or poor maintenance; ie, check that the air cleaner filter element is clean, the spark plugs are in good condition and correctly gapped, that the engine breather hoses are clear and undamaged, referring to Chapter 1 for further information. Also check 3510 Vauxhall/Opel Omega that the accelerator cable is correctly adjusted as described in Chapter 4A. If the engine is running very roughly, check the compression pressures as described in Chapter 2A. Whilst checking the spark plugs, also check the HT leads as follows. 2 Check inside the HT lead end fitting for signs of corrosion, which will look like a white crusty powder. Push the end fitting back onto the spark plug, ensuring that it is a tight fit on the plug. If not, remove the lead again and use pliers to carefully crimp the metal connector inside the end fitting until it fits securely on the end of the spark plug. 3 Using a clean rag, wipe the entire length of the lead to remove any built-up dirt and grease. Once the lead is clean, check for burns, cracks and other damage. Do not bend the lead excessively, nor pull the lead lengthwise - the conductor inside might break. 4 Disconnect the other end of the lead from the DIS module (see Section 3) and check for corrosion and a tight fit in the same manner as the spark plug end. Ensure that the leads are numbered before removing them, to avoid confusion when refitting. Pull the leads from the plugs by gripping the end fitting, not the lead, otherwise the lead connection may be fractured. Refit the lead securely on completion. 5 Check the remaining leads one at a time, in the same way. If new spark plug (HT) leads are required, purchase a set for your specific car and engine. 5B 5B•2 Ignition system 3.6 DIS module wiring connector (1) and HT leads (2) from the DIS module - 2.0 litre DOHC engine 6 If these checks fail to reveal the cause of the problem the vehicle should be taken to a suitably equipped Vauxhall dealer for testing. A wiring block connector is incorporated in the engine management circuit into which a special electronic diagnostic tester can be plugged (see Chapter 4A, Section 6). The tester will locate the fault quickly and simply alleviating the need to test all the system components individually which is a time consuming operation that carries a high risk of damaging the ECU. If necessary, the system wiring and wiring connectors can be checked, ensuring that the ECU wiring connector has first been disconnected. 3 DIS module removal and refitting 4 Removal 2.0 litre SOHC engine 1 The DIS module is mounted onto the rear of the cylinder head. Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands; access can then be gained both from above and below. 2 Ensure the ignition is switched off then disconnect the wiring connector from the DIS module. 3 Slacken and remove the bolts securing the DIS module mounting bracket to the cylinder head noting the correct fitted location of the engine lifting bracket. Free the wiring from the bracket then manoeuvre the module and bracket assembly out from behind the cylinder head. 3.8 On 2.5 and 3.0 litre engines the DIS module is mounted on the rear of the left-hand cylinder head (later model shown with engine removed) 4 Disconnect the HT leads from the DIS module and remove the module from the vehicle. The module HT lead terminals are numbered (the leads should also be numbered) with their respective cylinder number to avoid confusion on refitting. If necessary, undo the bolts and separate the module and bracket. 2.0 litre DOHC engine 5 Undo the retaining screws and remove the spark plug cover from the cylinder head cover. 6 Ensure the ignition is switches off then disconnect the wiring connector and HT leads from the DIS module (see illustration). The module HT lead terminals are numbered (the leads should also be numbered) with their respective cylinder number to avoid confusion on refitting. 7 Slacken and remove the retaining bolts and remove the DIS module from the rear of the cylinder head. 2.5 and 3.0 litre engine 8 The DIS module is mounted onto the rear of the left-hand cylinder head (see illustration). To gain access to the module remove the wiper motor as described in Chapter 12. The module is very awkward to remove; access can by further improved by unclip the wiring connector holder from the lifting bracket on the rear of the cylinder head and disconnecting the pipes/hoses which pass over the module. 9 Slacken and remove the retaining bolts and free the module from cylinder head. On early models the module is bolted directly onto the head (as opposed to being mounted on a bracket on later models), access to the lower bolts may be easier from below once the 3510 Vauxhall/Opel Omega vehicle has been raised and supported. 10 Disconnect the wiring connector and HT leads from the DIS module and remove the module from the vehicle. The module HT lead terminals are numbered (the leads should also be numbered) with their respective cylinder number to avoid confusion on refitting. Refitting 11 Refitting is the reverse of removal, ensuring each HT lead is securely reconnected to its corresponding terminal on the DIS module using the numbers on the leads and module. Tighten the retaining bolts to the specified torque and securely reconnect the wiring connector. 4 Ignition timing checking and adjustment 5 1 There are no timing marks on the flywheel or crankshaft pulley. The timing is constantly being monitored and adjusted by the engine management ECU, and nominal values cannot be given. Therefore, it is not possible for the home mechanic to check the ignition timing. 2 The only way in which the ignition timing can be checked and (where possible) adjusted is by using special electronic test equipment, connected to the engine management system diagnostic connector (refer to Chapter 4A, Section 6 for further information). Refer to your Vauxhall dealer for further information. 6•1 Chapter 6 Clutch Contents Clutch assembly - removal, inspection and refitting . . . . . . . . . . . . . 6 Clutch hydraulic system - bleeding . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Clutch pedal - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 5 Fluid level check . . . . . . . . . . . . . . . . . . . . . . . . . . .See Weekly checks General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Master cylinder - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 3 Release cylinder - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 4 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications Type ................................................... Single dry plate with diaphragm spring, hydraulically operated Friction plate Diameter: 2.0 litre engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 litre engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torque wrench settings Bleed screw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic pipe union nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Master cylinder retaining nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pedal: Mounting bracket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pivot bolt nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pressure plate retaining bolts: M7 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M8 bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Release cylinder mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 General information 1 The clutch consists of a friction plate, a pressure plate assembly, and the hydraulic release cylinder and bearing; all of these components are contained in the large castaluminium alloy bellhousing, sandwiched between the engine and the transmission. 2 The friction plate is fitted between the 216 mm 228 mm 240 mm Nm 9 14 20 lbf ft 7 10 15 18 18 13 13 15 28 22 11 21 16 engine flywheel and the clutch pressure plate, and is allowed to slide on the transmission input shaft splines. 3 The pressure plate assembly is bolted to the engine flywheel. When the engine is running, drive is transmitted from the crankshaft, via the flywheel, to the friction plate (these components being clamped securely together by the pressure plate assembly) and from the friction plate to the transmission input shaft. 4 To interrupt the drive, the spring pressure 3510 Vauxhall/Opel Omega must be relaxed. This is achieved using a hydraulic release mechanism which consists of the master cylinder, the release cylinder and the pipe/hose linking the two components. Depressing the pedal pushes on the master cylinder pushrod which hydraulically forces the release cylinder bearing against the pressure plate spring fingers. This causes the springs to deform and releases the clamping force on the friction plate. 5 The clutch is self-adjusting and requires no manual adjustment. 6 6•2 Clutch 2 Clutch hydraulic system bleeding 3 Warning: Hydraulic fluid is poisonous; wash off immediately and thoroughly in the case of skin contact, and seek immediate medical advice if any fluid is swallowed or gets into the eyes. Certain types of hydraulic fluid are flammable, and may ignite when allowed into contact with hot components; when servicing any hydraulic system, it is safest to assume that the fluid is flammable, and to take precautions against the risk of fire as though it is petrol that is being handled. Hydraulic fluid is also an effective paint stripper, and will attack plastics; if any is spilt, it should be washed off immediately, using copious quantities of fresh water. Finally, it is hygroscopic (it absorbs moisture from the air) - old fluid may be contaminated and unfit for further use. When topping-up or renewing the fluid, always use the recommended type, and ensure that it comes from a freshly opened sealed container. 1 The correct operation of any hydraulic system is only possible after removing all air from the components and circuit; this is achieved by bleeding the system. 2 During the bleeding procedure, add only clean, unused hydraulic fluid of the recommended type; never re-use fluid that has already been bled from the system. Ensure that sufficient fluid is available before starting work. 3 If there is any possibility of incorrect fluid being already in the system, the hydraulic circuit must be flushed completely with uncontaminated, correct fluid. 4 If hydraulic fluid has been lost from the system, or air has entered because of a leak, ensure that the fault is cured before continuing further. 5 The bleed screw is located on the righthand side of the transmission bellhousing (see illustration). To gain access, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands so that the screw can be reached from below. 6 Check that all pipes and hoses are secure, unions tight and the bleed screw is closed. Clean any dirt from around the bleed screw. 7 Unscrew the master cylinder fluid reservoir cap (the clutch shares the same fluid reservoir as the braking system), and top the master cylinder reservoir up to the upper (MAX) level line. Refit the cap loosely, and remember to maintain the fluid level at least above the lower (MIN) level line throughout the procedure, or there is a risk of further air entering the system. 8 There are a number of one-man, do-ityourself bleeding kits currently available from motor accessory shops. It is recommended that one of these kits is used whenever possible, as they greatly simplify the bleeding operation, and reduce the risk of expelled air and fluid being drawn back into the system. If such a kit is not available, the basic (two-man) method must be used, which is described in detail below. 9 If a kit is to be used, prepare the vehicle as described previously, and follow the kit manufacturer’s instructions, as the procedure may vary slightly according to the type being used; generally, they are as outlined below in the relevant sub-section. Bleeding basic (two-man) method 10 Collect a clean glass jar, a suitable length of plastic or rubber tubing which is a tight fit over the bleed screw, and a ring spanner to fit the screw. The help of an assistant will also be required. 11 Remove the dust cap from the bleed screw. Fit the spanner and tube to the screw, place the other end of the tube in the jar, and pour in sufficient fluid to cover the end of the tube. 12 Ensure that the fluid level is maintained at least above the lower level line in the reservoir throughout the procedure. 13 Have the assistant fully depress the clutch pedal several times to build up pressure, then maintain it on the final downstroke. 14 While pedal pressure is maintained, unscrew the bleed screw (approximately one turn) and allow the compressed fluid and air to flow into the jar. The assistant should maintain pedal pressure and should not release it until instructed to do so. When the flow stops, tighten the bleed screw again, have the assistant release the pedal slowly, and recheck the reservoir fluid level. 15 Repeat the steps given in paragraphs 13 and 14 until the fluid emerging from the bleed screw is free from air bubbles. If the master cylinder has been drained and refilled allow approximately five seconds between cycles for the master cylinder passages to refill. 16 When no more air bubbles appear, tighten the bleed screw to the specified torque, remove the tube and spanner, and refit the dust cap. Do not overtighten the bleed screw. Bleeding using a one-way valve kit 17 As their name implies, these kits consist of a length of tubing with a one-way valve fitted, to prevent expelled air and fluid being drawn back into the system; some kits include a translucent container, which can be positioned so that the air bubbles can be more easily seen flowing from the end of the tube. 18 The kit is connected to the bleed screw, which is then opened. The user returns to the driver’s seat, depresses the clutch pedal with a smooth, steady stroke, and slowly releases it; this is repeated until the expelled fluid is clear of air bubbles. 19 Note that these kits simplify work so much that it is easy to forget the clutch fluid reservoir level; ensure that this is maintained at least above the lower level line at all times. Bleeding using a pressure-bleeding kit 20 These kits are usually operated by the reservoir of pressurised air contained in the spare tyre. However, note that it will probably be necessary to reduce the pressure to a lower level than normal; refer to the instructions supplied with the kit. 21 By connecting a pressurised, fluid-filled container to the clutch fluid reservoir, bleeding can be carried out simply by opening the bleed screw and allowing the fluid to flow out until no more air bubbles can be seen in the expelled fluid. 22 This method has the advantage that the large reservoir of fluid provides an additional safeguard against air being drawn into the system during bleeding. All methods 23 When bleeding is complete, and correct pedal feel is restored, tighten the bleed screw to the specified torque and wash off any spilt fluid. Refit the dust cap to the bleed screw. 24 Check the hydraulic fluid level in the master cylinder reservoir, and top-up if necessary (see Weekly checks). 25 Discard any hydraulic fluid that has been bled from the system; it will not be fit for re-use. 26 Check the operation of the clutch pedal. If the clutch is still not operating correctly, air must still be present in the system, and further bleeding is required. Failure to bleed satisfactorily after a reasonable repetition of the bleeding procedure may be due to worn master cylinder/release cylinder seals. 3 Master cylinder removal and refitting 3 Removal 2.5 Clutch bleed screw location (arrowed) 3510 Vauxhall/Opel Omega 1 On 2.5 and 3.0 litre right-hand drive models and all left-hand drive models, to improve access to the master cylinder remove the Clutch 6•3 windscreen wiper arms and the water deflector panel from the base of the windscreen (see Chapter 12, Sections 15 and 16). 2 On all models, remove all traces of dirt from the outside of the master cylinder and position some cloth beneath the cylinder to catch any spilt fluid. 3 Slacken the retaining clip then disconnect the master cylinder hose from the reservoir outlet. Plug the reservoir outlet to minimise fluid loss then wash off any spilt fluid immediately. 4 Slide out the retaining clip and free the hydraulic pipe from the front of the master cylinder. Plug pipe end and master cylinder port to minimise fluid loss and prevent the entry of dirt. Refit the retaining clip to the master cylinder groove, ensuring its is correctly located. 5 From inside the vehicle, release the retaining clips (rotate them through 90º) then remove the undercover panel from the drivers’ side of the facia. Remove the fastener (prise out the centre pin then pull out the fastener outer section) then unclip and remove the heater/ventilation duct to improve access to the pedal. 6 Slide off the retaining clip and remove the clevis pin securing the master cylinder pushrod to the pedal then slacken and remove the cylinder retaining nuts. 7 Return to the engine compartment and remove the master cylinder from the vehicle noting that it maybe necessary to unclip the brake pipes from the bulkhead to gain the necessary clearance required. If the master cylinder is faulty it must be renewed; overhaul of the unit is not possible. Refitting 8 Ensure the cylinder and bulkhead mating surfaces then manoeuvre the master cylinder into position. 9 From inside the vehicle, ensure the pushrod clevis is correctly engaged with the pedal then refit the master cylinder retaining nuts, tightening them to the specified torque. 10 Apply a smear of multi-purpose grease to the clevis pin then align the clevis and pedal and insert the pin. Secure the clevis pin in position with the retaining clip, making sure it is correctly located in the pin groove, then refit the heater/ventilation duct and facia undercover. 11 Working in the engine compartment, ensure that the retaining clip is correctly located in the master cylinder groove and the clutch pipe sealing ring is in good condition. Ease the pipe union into position until the retaining clip is heard to click then check that the pipe is securely retained. 12 Reconnect the master cylinder pipe to the fluid reservoir outlet and securely tighten its retaining clip. 13 Where necessary, refit the water deflector panel and bulkhead sealing strip then refit both windscreen wiper arms (see Chapter 12). 14 Top up the fluid reservoir and bleed the clutch hydraulic system (see Section 2). 4 Release cylinder removal and refitting 4 Removal Note: Refer to the warning concerning the dangers of asbestos dust at the beginning of Section 6. 1 Remove the transmission unit as described in Chapter 7A. 2 Remove the release bearing from the cylinder noting which way around it is fitted. 3 Wipe clean the outside of the release cylinder then slacken the union nut securing the feed pipe to the cylinder. Free the rubber grommet from the transmission housing and remove the pipe assembly. 4 Slacken the union nut and free the bleed screw pipe from the release cylinder. If necessary, slide off the retaining clip and remove the bleed screw assembly from the transmission housing. 5 Unscrew the three retaining bolts and slide the release the cylinder off from the transmission input shaft. Remove the sealing ring which is fitted to the rear of the release cylinder and discard it; a new one must be used on refitting. Whilst the cylinder is removed, take care not to allow any debris to enter the transmission unit. 6 The release cylinder is a sealed unit and must be renewed if faulty. The only component which can be replaced is the input shaft seal which is fitted to the rear of the cylinder (see Chapter 7A, Section 5). 7 Also check the release bearing noting that it is often considered worthwhile to renew it as a matter of course. Check that the contact surface rotates smoothly and easily, with no sign of noise or roughness, and that the surface itself is smooth and unworn, with no signs of cracks, pitting or scoring. If there is any doubt about its condition, the bearing must be renewed. Refitting 8 If the original cylinder is being refitted it is recommended that the input shaft oil seal is renewed, regardless of its apparent condition (see Chapter 7A, Section 5). 9 Ensure the release cylinder and transmission mating surfaces are clean and dry and fit the new sealing ring to the recess on the rear of the release cylinder. 10 Lubricate the release cylinder seal with a smear of transmission oil then carefully ease the cylinder along the input shaft and into position. Ensure the sealing ring is still correctly seated in its groove then refit the release cylinder retaining bolts and tighten them to the specified torque. 11 Reconnect the bleed screw pipe to the release cylinder and tighten its union nut to the specified torque. Where necessary secure the bleed screw assembly in position with the retaining clip. 3510 Vauxhall/Opel Omega 12 Reconnect the feed pipe to the release cylinder and seat the sealing grommet in the transmission housing. Make sure the pipe is centrally position in the housing aperture then tighten the union nut to the specified torque. 13 Lubricate the inner bore of the release bearing with a smear of high temperature grease (Vauxhall recommend the use of lubricating paste 19 42 530 - available from your Vauxhall dealer); do apply too much or there is risk of the clutch friction plate becoming contaminated. Fit the release bearing to the cylinder making sure it is the correct way around. 14 Refit the transmission unit as described in Chapter 7A. 5 Clutch pedal removal and refitting 3 Removal 1 From inside the vehicle, release the retaining clips (rotate them through 90º) then remove the undercover panel from the drivers’ side of the facia. Remove the fastener (prise out the centre pin then pull out the fastener outer section) then unclip and remove the heater/ventilation duct to improve access to the pedals. 2 Slide off the retaining clip and remove the clevis pin securing the master cylinder pushrod to the pedal. 3 Where necessary, disconnect the wiring connector from the clutch pedal switch. 4 Slacken and remove the master cylinder retaining nuts and free the cylinder pushrod from the pedal. 5 Fully depress the clutch pedal then slacken and remove the pedal mounting bracket upper retaining bolt and manoeuvre the pedal assembly out from underneath the facia. 6 If necessary, clamp the pedal bracket firmly in a vice and disassemble as follows. 7 On 2.0 litre engine models unhook the return spring, noting its correct fitted position. Remove the retaining clip from the pivot bolt nut then slacken and remove the nut and washer. Remove the pivot bolt and separate the pedal and return spring from the mounting bracket. 8 On 2.5 and 3.0 litre engine models carefully unhook the return spring lower end fitting from the pedal and remove the spring assembly noting which way around the end fittings are positioned. Remove the retaining clip from the pivot bolt nut then slacken and remove the nut and washer. Remove the pivot bolt and separate the pedal from the mounting bracket noting the correct fitted location of the thrustwasher. 9 On all models check the pedal components for signs of damage. If any components is worn or damage it should be renewed. 6 6•4 Clutch position with the retaining clip, making sure it is correctly located in the pin groove 15 Reconnect the wiring connector to the clutch pedal switch (where fitted) then refit the heater/ventilation duct and facia undercover. 6 Clutch assembly removal, inspection and refitting 6.3 Vauxhall service tool for depressing the diaphragm spring on engines with a normal flywheel Arrows indicate where pressure plate retaining clips are fitted Refitting 10 If the pedal and bracket assembly has been dismantled, apply a smear of multipurpose grease to the pedal pivot bolt and bushes prior to reassembly. 11 On 2.0 litre engine models, fit the return spring to the pedal then refit the assembly to the mounting bracket. Insert the pivot bolt then refit the washer and nut, tightening it to the specified torque. Secure the pivot bolt nut in position with the retaining clip then hook the return spring back into position. 12 On 2.5 and 3.0 litre engine models refit the pedal to the mounting bracket then, making sure the thrustwasher is correctly positioned, insert the pivot bolt. Refit the washer and nut to the pivot bolt then tighten it to the specified torque and secure in position with the retaining clip. Ensure the end fittings are correctly seated on the return spring then refit the assembly to the pedal and bracket making sure the smaller end fitting is positioned at the pedal end. 13 On all models, manoeuvre the pedal and bracket assembly into position and refit the upper retaining bolt. Engage the master cylinder pushrod with the pedal then refit the master cylinder retaining nuts. Tighten both the master cylinder nuts and the pedal bracket bolt to their specified torque settings. 14 Apply a smear of multi-purpose grease to the clevis pin then align the clevis and pedal and insert the pin. Secure the clevis pin in 6.14 Refit the friction plate making sure its spring hub assembly faces away from the flywheel 4 Warning: Dust created by clutch wear and deposited on the clutch components may contain asbestos, which is a health hazard. DO NOT blow it out with compressed air, or inhale any of it. DO NOT use petrol or petroleum-based solvents to clean off the dust. Brake system cleaner or methylated spirit should be used to flush the dust into a suitable receptacle. After the clutch components are wiped clean with rags, dispose of the contaminated rags and cleaner in a sealed, marked container. Note: Although some friction materials may no longer contain asbestos, it is safest to assume that they do, and to take precautions accordingly. Removal 1 Remove the transmission as described in Chapter 7A. 2 Before disturbing the clutch, use chalk or a marker pen to mark the relationship of the pressure plate assembly to the flywheel. 3 Working in a diagonal sequence, evenly and progressively slacken the pressure plate bolts by half a turn at a time, until spring pressure is released and the bolts can be unscrewed by hand. Caution: To avoid the risk of distorting the pressure plate diaphragm spring it is most important that the pressure plate bolts are evenly slackened. To avoid this, on models with a normal flywheel (it is not possible if a dual-mass flywheel is fitted) Vauxhall dealers use a special tool to depress the diaphragm spring and then hold the spring in its compressed state by fitting special clips to the pressure plate assembly (see illustration). Removal of the clips and fitting to a new pressure plate will then 6.17 Centralising the friction plate with an aligning tool 3510 Vauxhall/Opel Omega require the use of a press. However, provided adequate care is taken to unscrew the pressure plate bolts evenly no distortion should occur. 4 Remove the pressure plate assembly and collect the friction plate, noting which way round the friction plate is fitted. Inspection Note: Due to the amount of work necessary to remove and refit clutch components, it is usually considered good practice to renew the clutch friction plate, pressure plate assembly and release bearing as a matched set, even if only one of these is actually worn enough to require renewal. It is also worth considering the renewal of the clutch components on a preventive basis if the engine and/or transmission have been removed for some other reason. 5 Remove the clutch assembly. 6 When cleaning clutch components, read first the warning at the beginning of this Section; remove dust using a clean, dry cloth, and working in a well-ventilated atmosphere. 7 Check the friction plate facings for signs of wear, damage or oil contamination. If the friction material is cracked, burnt, scored or damaged, or if it is contaminated with oil or grease (shown by shiny black patches), the friction plate must be renewed. 8 If the friction material is still serviceable, check that the centre boss splines are unworn, that the torsion springs are in good condition and securely fastened, and that all the rivets are tight. If any wear or damage is found, the friction plate must be renewed. 9 If the friction material is fouled with oil, this must be due to an oil leak from the crankshaft oil seal, from the sump-to-cylinder block joint, or from the release cylinder assembly (either the input shaft seal or the sealing ring). Renew the crankshaft oil seal or repair the sump joint as described in the relevant part of Chapter 2, before installing the new friction plate. The clutch release cylinder is covered in Section 4. 10 Check the pressure plate assembly for obvious signs of wear or damage; shake it to check for loose rivets or worn or damaged fulcrum rings, and check that the drive straps securing the pressure plate to the cover do not show signs (such as a deep yellow or blue discoloration) of overheating. If the diaphragm spring is worn or damaged, or if its pressure is in any way suspect, the pressure plate assembly should be renewed. 11 Examine the machined bearing surfaces of the pressure plate and of the flywheel; they should be clean, completely flat, and free from scratches or scoring. If either is discoloured from excessive heat, or shows signs of cracks, it should be renewed - although minor damage of this nature can sometimes be polished away using emery paper. 12 Also check that the release cylinder bearing rotates smoothly and easily, with no sign of noise or roughness. Also check that the surface itself is smooth and unworn, with Clutch 6•5 no signs of cracks, pitting or scoring. If there is any doubt about its condition, the bearing should be renewed (see Section 4). Refitting 13 On reassembly, ensure that the bearing surfaces of the flywheel and pressure plate are completely clean, smooth, and free from oil or grease. Use solvent to remove any protective grease from new components. 14 Fit the friction plate so that its spring hub assembly faces away from the flywheel; there may also be a marking showing which way round the plate is to be refitted (see illustration). 15 Refit the pressure plate assembly, aligning the marks made on dismantling (if the original pressure plate is re-used). Fit the pressure plate bolts, but tighten them only finger-tight, so that the friction plate can still be moved. 16 The friction plate must now be centralised, so that when the transmission is refitted, its input shaft will pass through the splines at the centre of the friction plate. 17 Centralisation can be achieved by passing a screwdriver or other long bar through the friction plate and into the hole in the crankshaft; the friction plate can then be moved around until it is centred on the crankshaft hole. Alternatively, a clutchaligning -tool can be used to eliminate the guesswork; these can be obtained from most accessory shops (see illustration). A homemade aligning tool can be fabricated from a length of metal rod or wooden dowel which fits closely inside the crankshaft hole, and has insulating tape wound around it to match the diameter of the friction plate splined hole. 18 When the friction plate is centralised, tighten the pressure plate bolts evenly and in a diagonal sequence to the specified torque setting. Once all the bolts have been tightened remove the alignment tool. Where necessary, use the service tool to remove the retaining clips from the pressure plate. Caution: To avoid the risk of distorting the pressure plate diaphragm spring it is most important that the pressure plate bolts are evenly and progressively tightened. 19 Refit the transmission as described in Chapter 7A. 6 3510 Vauxhall/Opel Omega 7A•1 Chapter 7 Part A: Manual transmission Contents Gearchange linkage - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . Gearchange linkage - removal and refitting . . . . . . . . . . . . . . . . . . . General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4 1 5 Reversing light switch - testing, removal and refitting . . . . . . . . . . . Transmission - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . Transmission oil - draining, refilling and checking . . . . . . . . . . . . . . . Transmission overhaul - general information . . . . . . . . . . . . . . . . . . 6 7 2 8 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications General Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Identification code: 2.0 and 2.5 litre engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual, five forward speeds and reverse. Synchromesh on all forward speeds R25 R28 Torque wrench settings Nm Drain plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Engine to transmission support bracket bolts - 2.0 litre engines with one-piece sump: Bracket-to-engine bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Bracket-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Filler plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Gearchange lever retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Gearchange linkage rod clamp bolt: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten a further 135 to 180º Propeller shaft flange nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Reversing light switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Transmission unit mounting bolts: Transmission-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . . . . . . 60 Transmission-to-sump flange bolts (engines with a two-piece sump) . 40 Rear upper mounting bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Rear mounting crossmember-to-body bolts . . . . . . . . . . . . . . . . . . . 45 lbf ft 22 30 16 22 7 10 110 15 44 30 16 33 7A 1 General information 1 The transmission is contained in a castaluminium alloy casing bolted to the rear of the engine. Drive is transmitted from the crankshaft via the clutch to the transmission input shaft, which has a splined extension to accept the clutch friction plate. The transmission input shaft transfers drive to the auxiliary shaft which is positioned directly below the main shaft, both shafts being parallel to the crankshaft and propeller shaft. 2 Gear selection is via a floor-mounted lever and selector linkage mechanism. The selector linkage cause the appropriate selector fork to move its respective synchro-sleeve along the shaft, to lock the gear pinion to the synchrohub. Since the synchro-hubs are splined to the main shaft, this locks the pinion to the shaft, so that drive can be transmitted. To ensure that gear-changing can be made quickly and quietly, a synchro-mesh system is fitted to all forward gears, consisting of baulk rings and spring-loaded fingers, as well as the gear pinions and synchro-hubs. The synchromesh cones are formed on the mating faces of the baulk rings and gear pinions. 3510 Vauxhall/Opel Omega 2 Transmission oil draining, refilling and checking 3 Note: There have been three different types of oil used in the manual transmission unit by Vauxhall (see Lubricants and fluids in Weekly checks). Bearing in mind that the different types of oil should never be mixed, it is essential that the transmission unit is refilled either with the same type of oil as that which has been drained or the very latest specification oil (used in production from 1999 model year onwards). If it is not known what type of oil has been drained, 7A•2 Manual transmission Warning: If the oil is hot, take precautions against scalding. 5 When the oil has finished draining, clean the drain plug threads and those of the transmission casing then refit the drain plug and tighten to the specified torque. Refilling 2.4 Removing the transmission drain plug the transmission unit should be flushed before filling with the latest specification oil. To do this, using the latest type of oil (part number 19 40 768), refill the transmission unit so that the oil level is right up to the base of the filler plug aperture then refit the plug. Take the vehicle on a journey of approximately 15 miles (20 km) then, on your return, drain the oil out again and refill the transmission as normal with the latest type of oil. If the flushing process has already been carried out an early (pre 1999 model year) vehicle, the drain plug will be marked with a dot of green paint. 6 Refilling the transmission is an extremely awkward operation. Above all, allow plenty of time for the oil level to settle properly before checking it. Note that the car must be parked on flat level ground when checking the oil level. 7 Refill the transmission with the exact amount of the specified type of oil then check the oil level as described in paragraphs 12 and 13. When the level is correct, refit the filler plug and tighten it to the specified torque. 8 Take the vehicle on a short journey so that the new oil is distributed fully around the transmission components. 9 On your return, park the vehicle on level ground and recheck the transmission oil level again to ensure the level is correct. of a piece of welding rod with a right-angled bend in it. Insert the rod into the filler hole and check the oil level; the oil level should be approximately 9 mm below the lower edge of the filler plug aperture. Caution: When checking the oil level, take great care not to drop the dipstick into the transmission unit. 13 If topping up is necessary, add the correct type of oil through the filler hole until the oil level is correct. Note: Do not overfill the transmission as this will adversely affect the gearchange action. Any excess oil must be either be siphoned or drained from the transmission unit before the vehicle is used. 14 Once the transmission oil level is correct, refit the filler plug and tighten it to the specified torque. 3 Gearchange linkage adjustment 3 1 This operation is much quicker and more efficient if the car is first taken on a journey of sufficient length to warm the engine/transmission up to normal operating temperature. 2 Park the car on level ground, switch off the ignition and apply the handbrake firmly. For improved access, jack up the front of the car and support it securely on axle stands. Note that the car must be lowered to the ground and level, to ensure accuracy, when refilling and checking the oil level. 3 Remove all traces of dirt then unscrew the filler plug from the right-hand side of the transmission housing. 4 Position a suitable container under the drain plug situated on the base of the transmission housing then unscrew the drain plug and allow the oil to drain completely into the container (see illustration). Clean both the filler and the drain plugs, being especially careful to wipe any metallic particles off the magnetic inserts. Note: It is essential that the transmission unit is topped up with the same type of oil as that with which it is filled; there are three different types of oil available and they must never be mixed. If it is not known which type of oil the transmission is filled with, it is recommended that the unit is drained, flushed and then refilled with the latest type of oil (see Note at the start of the Section). 10 Position the vehicle over an inspection pit, on vehicle ramps, or jack it up, but make sure that it is level. The oil level must be checked before the car is driven, or at least 5 minutes after the engine has been switched off. If the oil is checked immediately after driving the car, some of the oil will remain distributed around the transmission components, resulting in an inaccurate level reading. 11 Wipe clean the area around the filler plug which is located on the right-hand side of the transmission housing. Unscrew the plug and clean it. 12 To check the oil level, it will be necessary to fabricate a dipstick. This can be made out Note: Vauxhall service tool KM-631A will be required to carry out this procedure. 1 Adjustment of the gearchange linkage is not a routine operation and should only be needed if the mechanism has been removed. If the gearchange action is stiff or imprecise, check that it is correctly adjusted as follows. 2 Position the gearchange lever in the neutral position, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 3 Remove the retaining clips securing the protective cover to the vehicle underbody then fold the cover forwards to gain access to the clamp bolt on the rear end of the gearchange linkage rod. Slacken the clamp bolt so that the end fitting is free to move easily in the rod (see illustrations). 4 From inside the vehicle, unclip the gearchange lever gaiter from the centre console and fold it back over the lever. Free the rubber gaiter from the mounting plate and fold it back to gain access to the base of the gearchange lever. 5 Lock the gearchange lever in position by fitting the service tool (KM-631A) into the gearchange lever housing whilst holding the lever over to the right. 3.3a Release the retaining clips (arrowed) . . . 3.3b . . . and peel back the protective cover . . . 3.3c . . . to gain access to the gearchange linkage clamp bolt (arrowed) Draining Checking 3510 Vauxhall/Opel Omega Manual transmission 7A•3 6 From underneath the vehicle, using an openended spanner on the flats provided, turn the gearchange linkage rod fully clockwise (as viewed from the rear of the vehicle). Hold the rod in this position then tighten the rod clamp bolt first to the specified stage 1 torque and then through the specified stage 2 angle. 7 Remove the service tool and check the operation of the gearchange lever before seating the rubber gaiter onto its mounting and clipping the gaiter back into the centre console. 8 Ensure the protective cover is correctly seated on the base of the gearchange lever, securing it in position with the retaining clips, then lower the vehicle to the ground. 4 Gearchange linkage removal and refitting 3 Removal Gearchange lever 1 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 2 Remove the retaining clips securing the protective cover to the vehicle underbody then fold the cover forwards to gain access to the base of the gearchange lever (see illustrations 3.3a and 3.3b). 3 Slide off the retaining clip and withdraw the pivot pin from the lever end of the linkage rod (see illustration). Free the rod from the base of the gearchange lever taking care not to lose the pivot bushes. 4 Slacken and remove the four bolts securing the lever assembly to the floor. 5 From inside the vehicle, unclip the gearchange lever gaiter from the centre console and fold it back over the lever. 6 Free the rubber gaiter from the mounting plate and remove the lever assembly from the vehicle, taking care not to lose the threaded retaining plates. Recover the sealing washer which is fitted between the lever mounting and floor. 7 Check the lever assembly for signs of wear or damage and renew damaged components as necessary. 4.3 Slide off the retaining clip (arrowed) then withdraw the pivot pin securing the linkage rod to the gearchange lever 4.9 Slacken and remove the nut and pivot bolt (arrowed) securing the linkage rod to the transmission unit and the threaded retaining plates with multipurpose grease (Vauxhall recommend the use of grease 19 48 606 or 19 48 608 - available from your Vauxhall dealer) and stick the sealing washer to the base of the mounting. 11 Ensure the retaining plates are correctly positioned then refit the lever assembly to the vehicle. Make sure the lever mounting lugs are correctly seated (the larger lug should be at the rear) then refit the retaining bolts and tighten them to the specified torque. 12 Align the linkage rod with the lever then insert the pivot pin and secure it in position with the retaining clip. Ensure the protective cover is correctly seated on the base of the gearchange lever and secure it in position with the retaining clips. 13 Seat the gearchange lever rubber gaiter onto its mounting and clipping the gaiter back into the centre console. transmission flange and remove the vibration damper (where fitted). If necessary, to improve access to the flange remove the shaft completely. 2 To prevent the rotation as the shaft nut is slackened bolt a length of bar with two holes drilled in it to the flange. Alternatively, a tool can be fabricated from two lengths of steel strip (one long, one short) and a nut and bolt; the nut and bolt forming the pivot of a forked tool (see illustration). 3 Hold the flange then slacken and remove the retaining nut from the end of the transmission main shaft. Remove the holding tool and slide off the flange (see illustration). 4 Note the correct fitted depth of the seal in the transmission housing then carefully prise it out of position using a large flat-bladed screwdriver. 5 Check the propeller flange sealing surface for signs of wear or damage. If there is visible signs of damage, renew the flange. 6 Clean all traces of dirt from the area around the oil seal aperture and remove all traces of thread locking compound from the main shaft and flange nut threads. 7 Apply a smear of grease to the outer lip of the new oil seal then, making sure its sealing lip is facing inwards, slide it over the main shaft end. Tap the seal squarely into position, using a suitable tubular drift (such as a socket) which bears only on the hard outer edge of the seal, until it is positioned at the same depth in the housing that the original was. 8 Lubricate the seal with a smear of Linkage rod 14 Refitting is the reverse of removal lubricating the pivots with multi-purpose grease. 5 Oil seals renewal 4 Propeller shaft flange oil seal 1 Working as described in Chapter 8, free the front end of the propeller shaft from the 7A Linkage rod 8 Carry out the operations described in paragraphs 1 to 3. 9 Slacken and remove the nut and bolt securing the front end of the linkage rod to the transmission selector rod joint and remove the rod from underneath the vehicle (see illustration). Recover the spacer from the joint and inspect the joint pivot bushes for signs of wear. Refitting Gearchange lever 10 Lubricate the lever pivot ball and bushes 5.2 Slacken and remove the retaining nut whilst retaining the propeller shaft flange with a home-made tool . . . 3510 Vauxhall/Opel Omega 5.3 . . . then remove the flange from the output shaft (shown with transmission removed) 7A•4 Manual transmission transmission oil then carefully slide the propeller flange into position, taking care not to damage the seal lip. 9 Apply a few drops of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of the flange retaining nut. Refit the nut and tighten it to the specified torque using the method employed on removal to prevent rotation. 10 Reconnect/refit the propeller shaft as described in Chapter 8 then check the transmission oil level as described in Section 2. 4 Disconnect the wiring connector, then unscrew the switch and remove it from the transmission casing along with its sealing washer. Refitting 5 Fit a new sealing washer to the switch, then screw it back into position in the top of the transmission housing and tighten it to the specified torque. Reconnect the wiring connector and test the operation of the circuit then lower the vehicle to the ground. Input shaft oil seal Note: A leak around the transmission input shaft can come either from the input shaft seal or from the clutch release cylinder sealing ring. Whilst the cylinder is removed renew both items regardless of their apparent condition. 11 Remove the clutch release cylinder as described in Chapter 6. 12 Note the correct fitted depth of the seal in the release cylinder then carefully prise it out of position using a large flat-bladed screwdriver. 13 Clean all traces of dirt from the area around the oil seal aperture and apply a smear of grease to the outer lip of the new oil seal. Making sure its sealing lip is facing outward (towards the transmission unit when the cylinder is fitted), seat the seal in the rear of the cylinder and press it squarely into position until it is positioned at the same depth in the housing that the original was. If necessary, tap the seal into position, using a suitable tubular drift (such as a socket) which bears only on the hard outer edge of the seal. 14 Fit a new sealing ring and refit the release cylinder as described in Chapter 6. 6 Reversing light switch testing, removal and refitting 2 Testing 1 The reversing light circuit is controlled by a plunger-type switch that is screwed into the rear of the transmission, above and to the left of the propeller shaft. If a fault develops in the circuit, first ensure that the circuit fuse has not blown. 2 To test the switch, disconnect the wiring connector. Use a multimeter (set to the resistance function) or a battery-and-bulb test circuit to check that there is continuity between the switch terminals only when reverse gear is selected. If this is not the case, and there are no obvious breaks or other damage to the wires, the switch is faulty, and must be renewed. Removal 3 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 7 Transmission removal and refitting 4 Removal 1 Disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Chock the rear wheels, then firmly apply the handbrake. Jack up the front of the vehicle, and securely support it on axle stands. Undo the retaining bolts and remove the undercover from beneath the engine/transmission unit. 3 Trace the clutch hydraulic hose/pipe back from the transmission unit to connector on the engine compartment bulkhead. Minimise fluid loss by clamping the fluid supply hose linking the fluid reservoir to the clutch master cylinder then release the connector from the bulkhead. Slide out the retaining clip and separate the two halves of the pipe, plugging the pipe ends to minimise fluid loss and prevent the entry of dirt. Refit the retaining clip to the connector groove, ensuring its is correctly located, then check the lower end of the pipe is free to removed with the transmission unit. Caution: Do no depress the clutch pedal whilst the hose is disconnected. 4 Disconnect the wiring connector from the reversing light switch, which is located at the rear of the transmission unit. 5 Working as described in Chapter 8, unbolt the front end of the propeller shaft from the transmission flange and remove the vibration damper (where fitted). Position the propeller shaft to the right of the transmission unit and tie it to the vehicle underbody. 6 Remove the gearchange linkage rod as described in Section 4 and proceed as described under the relevant sub-heading. 2.0 litre engines 7 On SOHC engines, disconnect the wiring connector from the DIS module. Slacken and remove the module mounting bracket retaining bolts, noting the correct fitted location of the engine lifting bracket, then free the wiring harness and remove the DIS module and bracket from the rear of the 3510 Vauxhall/Opel Omega cylinder head. Free the HT leads from their retaining clips and position the assembly clear of the transmission unit. 8 On all models unclip the oxygen sensor wiring connector from transmission unit and disconnect it. 9 Slacken and remove the exhaust system front pipe mounting bracket retaining bolts and remove the bracket. Also remove the bolts securing the front pipe to the intermediate pipe and separate the two exhaust sections. 10 On models with a one-piece engine sump, slacken and remove the bolts securing the support brackets to the transmission housing and sides of the cylinder block. Remove both brackets from the engine then remove the flywheel lower cover plate from the base of the transmission housing. 11 On all models slacken and remove the two bolts securing the rear of the transmission unit to the upper mounting bracket. 12 Place a jack with a block of wood beneath the transmission, and raise the jack to take the weight of the transmission. 13 With the transmission securely supported, slacken and remove the bolts securing the transmission unit rear mounting crossmember to the vehicle body. 14 Lower the transmission unit slightly then slacken and remove all the bolts securing the transmission housing to the engine unit. Note the correct fitted positions of each bolt, and the necessary brackets, as they are removed, to use as a reference on refitting. Make a final check that all components have been disconnected, and are positioned clear of the transmission so that they will not hinder the removal procedure. 15 With the bolts removed, move the trolley jack and transmission to the rear, to free it from its locating dowels. Once the transmission is free, lower the jack and manoeuvre the unit out from under the vehicle. Remove the locating dowels from the transmission or engine if they are loose, and keep them in a safe place. 16 With the transmission removed from the vehicle, slide off the clutch release bearing from the release cylinder and check it for wear. The bearing contact surface should rotate smoothly and easily, with no sign of noise or roughness, and that the surface itself is smooth and unworn, with no signs of cracks, pitting or scoring. If there is any doubt about its condition, the bearing should be renewed. 2.5 and 3.0 litre engines 17 Remove both exhaust system front pipes as described in Chapter 4A. 18 Remove the transmission unit as described in paragraphs 11 to 16. Refitting 19 The transmission is refitted by a reversal of the removal procedure, bearing in mind the following points. Manual transmission 7A•5 a) Remove all traces of dirt and grease from the input shaft splines and the contact surfaces of the clutch release bearing and release cylinder. Lubricate the inner bore of the release bearing with a smear of high temperature grease (Vauxhall recommend the use of lubricating paste 19 42 530 - available from your Vauxhall dealer) and apply a thin smear of grease to the input shaft splines; do apply too much or there is risk of the clutch friction plate becoming contaminated. Fit the release bearing to the cylinder making sure it is the correct way around. b) Ensure the locating dowels are correctly positioned prior to refitting the transmission to the engine. As the transmission unit is fitted, take great care not to allow the weight of the unit to hang on the input shaft. c) Remove all traces of locking compound from the transmission unit rear mounting crossmember to body bolt threads. Apply a few drops of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of each bolt prior to refitting and tighten both bolts to the specified torque. d) Tighten all nuts and bolts to the specified torque (where given). e) Ensure the clutch hydraulic pipe connector sealing ring is in good condition before clipping the hose/pipe end fitting into position. Ensure the end fitting is securely retained by its clip then remove the clamp from the master cylinder hose and bleed the hydraulic system as described in Chapter 6. f) On completion check and, if necessary, top up the transmission oil level as described in Section 2. If necessary, also adjust the gearchange linkage as described in Section 3. 8 Transmission overhaul general information 5 1 Overhauling a manual transmission unit is a difficult and involved job for the DIY home mechanic. In addition to dismantling and reassembling many small parts, clearances must be precisely measured and, if necessary, changed by selecting shims and spacers. Internal transmission components are also often difficult to obtain, and in many instances, extremely expensive. Because of this, if the transmission develops a fault or becomes noisy, the best course of action is to have the unit overhauled by a specialist repairer, or to obtain an exchange reconditioned unit. 2 Nevertheless, it is not impossible for the more experienced mechanic to overhaul the transmission, provided the special tools are available, and the job is done in a deliberate step-by-step manner, so that nothing is overlooked. 3 The tools necessary for an overhaul include internal and external circlip pliers, bearing pullers, a slide hammer, a set of pin punches, a dial test indicator, and possibly a hydraulic press. In addition, a large, sturdy workbench and a vice will be required. 4 During dismantling of the transmission, make careful notes of how each component is fitted, to make reassembly easier and more accurate. 5 Before dismantling the transmission, it will help if you have some idea what area is malfunctioning. Certain problems can be closely related to specific areas in the transmission, which can make component examination and replacement easier. Refer to the Fault finding Section of this manual for more information. 7A 3510 Vauxhall/Opel Omega 7B•1 Chapter 7 Part B: Automatic transmission Contents Automatic transmission - removal and refitting . . . . . . . . . . . . . . . . . 9 Automatic transmission fluid level check . . . . . . . . . . . .See Chapter 1 Automatic transmission overhaul - general information . . . . . . . . . . 10 Fluid cooler - general information . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Oil seals - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Selector lever assembly - removal and refitting . . . . . . . . . . . . . . . . Selector linkage - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Selector linkage - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . Transmission control system electrical components - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transmission fluid - draining and refilling . . . . . . . . . . . . . . . . . . . . . 5 3 4 8 2 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications General Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Four-speed electronically-controlled automatic with three (normal, sport and winter) driving modes Identification code*: 2.0 and 2.5 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AR25 3.0 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AR35 *The code is marked on the identification plate which is attached to the left-hand side of the transmission unit, behind the selector lever. Torque wrench settings Nm Engine-to-transmission support bracket bolts - 2.0 litre engines with one-piece sump: Bracket-to-engine bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Bracket-to-transmission bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Fluid cooler pipe unions: Union bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Union nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Fluid filter retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Fluid level plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Output speed sensor bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Propeller shaft centre bearing bracket bolts . . . . . . . . . . . . . . . . . . . . . 20 Propeller shaft flange nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Rear mounting crossmember-to-body bolts . . . . . . . . . . . . . . . . . . . . . 45 Selector lever position switch bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Selector linkage fixings: Linkage rod clamp bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Lever pivot shaft nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Lever to transmission selector shaft nut . . . . . . . . . . . . . . . . . . . . . . . 20 Sump retaining bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Torque converter-to-driveplate bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Transmission unit mounting bolts: Transmission-to-cylinder block bolts . . . . . . . . . . . . . . . . . . . . . . . . . 60 Transmission-to-sump flange bolts (engines with a two-piece sump) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 1 General information Note: On later models, if the battery is disconnected with the selector lever in the P position, the lever will be locked in position. To manually release the lever, carefully unclip the selector lever gaiter from the top of the centre console then, depress the yellow release lever on the left-hand side of the selector lever with a pen or screwdriver (see illustrations). The selector lever can then be moved as normal. 1 Most models covered in this manual were offered with the option of a four-speed, 3510 Vauxhall/Opel Omega Ibf ft 30 16 18 22 15 24 9 15 74 33 10 6 21 15 9 22 44 30 electronically-controlled automatic transmission, consisting of a torque converter, an epicyclic geartrain, and hydraulically-operated clutches and brakes. The unit is controlled by the electronic control unit (ECU) via electrically-operated solenoid valves. The transmission unit has three driving modes; normal (economy), sport and winter modes. 7B 7B•2 Automatic transmission 2 Transmission fluid draining and refilling 3 1.0a On later models, to release the selector lever from the P position with the battery disconnected, unclip the selector lever gaiter . . . 1.0b . . . then depress the yellow release lever (arrowed) on the selector lever mounting 2 The normal (economy) mode is the standard mode for driving in which the transmission shifts up at relatively low engine speeds to combine reasonable performance with economy. If the transmission unit is switched into sport mode, using the button on the selector lever, the transmission shifts up only at high engine speeds, giving improved acceleration and overtaking performance. When the transmission is in sport mode, the indicator light in the instrument panel is illuminated. If the transmission is switched into winter mode, using the button on the centre console, the transmission will be select third gear as the vehicle pulls away from a standing start; this helps to maintain traction on very slippery surfaces. 3 The torque converter provides a fluid coupling between engine and transmission, which acts as an automatic clutch, and also provides a degree of torque multiplication when accelerating. 4 The epicyclic geartrain provides either of the four forward or one reverse gear ratios, according to which of its component parts are held stationary or allowed to turn. The components of the geartrain are held or released by brakes and clutches which are activated by the control unit. A fluid pump within the transmission provides the necessary hydraulic pressure to operate the brakes and clutches. 5 Driver control of the transmission is by a seven-position selector lever. The drive D position, allows automatic changing throughout the range of all four gear ratios. An automatic kickdown facility shifts the transmission down a gear if the accelerator pedal is fully depressed. The transmission also has three hold positions, 1 means only the first gear ratio can be selected, 2 allows both the first and second gear ratios position to be automatically selected and 3 allows automatic changing between the first three gear ratios. These hold positions are useful for providing engine braking when travelling down steep gradients. Note, however, that the transmission should never be shifted down a position at high engine speeds. 6 If the ECU senses a fault in the transmission operation it will illuminate the warning light on the instrument panel and the relevant fault code will be stored in the ECU memory. If the warning light comes on, the vehicle should be taken to a Vauxhall dealer at the earliest opportunity. A complete test of the transmission unit can then be carried out, using a special electronic diagnostic test unit which is simply plugged into the system’s diagnostic connector. The connector is located behind the fusebox cover panel on the drivers’ side of the facia. 7 Due to the complexity of the automatic transmission, any repair or overhaul work must be left to a Vauxhall dealer. The contents of the following Sections are therefore confined to supplying general information, and any service information and instructions that can be used by the owner. Note: A new main sump gasket will be required for this operation. If the intermediate sump is also to be removed, obtain a new gasket for that as well. 1 Since the transmission fluid is not renewed as part of the manufacturers maintenance schedule, no drain plug is fitted to the transmission. If for any reason the transmission needs to be drained, the only way of doing so is to remove the main sump and, if necessary, the intermediate sump. 2 Park the vehicle on level ground, switch off the ignition, and apply the handbrake firmly. For improved access, jack up the front of the car and support it securely on axle stands but note that the vehicle must be level when the transmission is refilled. 3 Position a container under the fluid level plug on the right-hand side of the transmission main sump. Unscrew the plug and remove it along with its sealing washer (see illustration). 4 Allow the fluid to drain out into the container then refit the level plug (see illustration). 5 Bearing in mind that the sump will still be full of oil, position a large container underneath the main sump. Evenly and progressively slacken and remove the sump retaining bolts, noting the correct location of the cooler pipe retaining clip(s) (see illustration). Carefully remove the sump and empty its contents into the container. Remove the gasket and discard it; a new one should be used on refitting. 6 To drain the transmission unit completely, slacken and remove the retaining bolts, then remove the intermediate sump from the transmission unit and empty its contents into the container. Remove the gasket and discard it; a new one should be used on refitting. 7 Whilst the main sump is removed, take the opportunity to check the transmission fluid filter. Undo the three retaining bolts, then remove the filter from the underside of the transmission (see illustrations). Clean the filter element in a bath of solvent, then examine the element for signs of clogging or damage. If the filter element is split or blocked 2.3 Slacken and remove the fluid level plug from the main sump . . . 2.4 . . . and allow the transmission fluid to drain into a suitable container 2.5 Unscrew the retaining bolts and remove the main sump from the transmission unit 3510 Vauxhall/Opel Omega Automatic transmission 7B•3 2.7a Undo the retaining bolts (arrowed) . . . 2.7b . . . and remove the fluid filter from the transmission unit or its seal is damaged, then the filter must be renewed (the seal is not available separately). 8 Remove all traces of dirt and fluid from the sump and transmission mating surfaces and wipe clean the inside of the sump(s). Remove the magnet from inside the main sump and clean all traces of metal filings from it; the filings should be very fine - any sizeable chips of metal indicate a worn component in the transmission (see illustration). Also remove all traces of locking compound from the threads of the sump retaining bolts. 9 Ensure that the filter element and transmission mating surfaces are clean and dry. Offer up the filter to the transmission then refit the retaining bolts and tighten them to the specified torque. 10 Where necessary, ensure the mating surfaces are clean and dry then refit the intermediate sump to the transmission unit, complete with a new gasket (see illustration). Apply a drop of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the each of the retaining bolts then refit the bolts, tightening them evenly and progressively to the specified torque setting. 11 Ensure the mating surfaces of the main sump and transmission unit are clean and dry. Fit a new gasket to the sump and apply a drop of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the each of the retaining bolts. Offer up the sump and gasket then refit the bolts, tightening them evenly and progressively to the specified torque setting (see illustration). 12 Refilling the transmission is an awkward operation, adding the specified type and amount of fluid to the transmission a little at a time via the level plug hole in the main sump. Ensure that the vehicle is level then fill the transmission with new fluid of the specified type allowing plenty of time for the fluid level to settle properly. Once the fluid level is up to the base of the level plug aperture with the engine stopped, it will be necessary to start the engine and add the rest of the fluid with the engine running. 13 Start the engine and allow it to idle then carefully add the rest of the fluid. Once the fluid level is up to the base of the level plug aperture, refit the level plug and sealing washer and tighten to the specified torque. 14 Take the car on a short run to fully distribute the new fluid around the transmission, then recheck the fluid level as described in Chapter 1 with the transmission at normal operating temperature. Once the fluid level is correct fit a new sealing washer to the level plug then refit the plug and tighten it to the specified torque. 2.10 Refit the intermediate sump using a new gasket 2.8 Clean all traces of metal fillings from magnet which is fitted inside the main sump selector lever position indicator. If adjustment is necessary, continue as follows. 2 Position the selector lever in the P (park) position. Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 3 Locate the selector lever on the left-hand side of the transmission unit and slacken the clamp bolt at the transmission end of the linkage rod (see illustration). Pull the transmission selector lever fully backwards to ensure it is located in the P (Park) position then tighten the linkage rod clamp bolt to the specified torque. 4 Check the operation of the selector lever and the position indicator switch. If necessary, adjust the switch as described in Section 8 then lower the vehicle to the ground. 4 Selector linkage removal and refitting 3 Removal 1 Operate the selector lever throughout its entire range and check that the transmission engages the correct gear indicated on the 1 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 2 Slide off the retaining clips then free the linkage rod from the transmission and selector lever and manoeuvre it out from underneath the vehicle (see illustration). Recover the bushes which are fitted to the lever pivot pins and renew them if they show signs of wear or damage. 2.11 Ensure the mating surfaces are clean and dry then refit the main sump complete with a new gasket 3.3 Slacken the clamp bolt (arrowed) and adjust the selector linkage as described in text 3 Selector linkage adjustment 3510 Vauxhall/Opel Omega 3 7B 7B•4 Automatic transmission Refitting 4.2 Slide off the retaining clip (arrowed) and detach the selector linkage rod from the selector lever Refitting 3 Apply a smear of multi-purpose grease to the linkage rod pivot pins. Ensure the bushes are in position then refit the rod to the transmission and selector lever and secure it in position with the retaining clips. 4 Check the operation of the selector linkage and, if necessary, adjust as described in Section 3 before lower the vehicle to the ground. 5 Selector lever assembly removal and refitting 3 Note: Renewal of the lever switches is covered in Section 8 Removal Note: A pop rivet gun and new rivets will be required on refitting. 1 Remove the centre console as described in Chapter 11 then position the selector lever in the P (park) position. 2 Firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 3 Slide off the retaining clip and detach the selector linkage rod from the base of the lever. Take care not to lose the lever pivot bush. 4 Slacken and remove the retaining nuts and bolt then remove the front and rear support brackets from the rear heater/ventilation duct. Unclip the duct and remove it from the around the selector lever. 5 Disconnect the wiring connector from the selector lever mode switch and unclip the wiring so that it is free to be removed with the lever. On later models were the lever is fitted with a selector lever pawl, remove the pawl switch and the ignition key release switch as described in Section 8. 6 Carefully drill off the heads from the rivets securing the lever mounting plate to the floor then ease the selector lever out of position. Recover seal (where fitted) which is fitted between the housing and floor. 7 Inspect the selector lever mechanism for signs of wear or damage and renew worn components as necessary 8 Ensure the mating surfaces of the lever mounting plate and body are clean and dry. Where a seal was fitted between the mounting plate and body ensure the seal is in good condition then position it on the body. Where no seal was fitted apply and thin film of sealant to the mating surface of the mounting plate to ensure a water-tight seal. 9 Manoeuvre the lever assembly into position and seat it on the body. Locate all the new pop rivets in the mounting plate holes to ensure the lever is correct positioned then secure all the rivets in position with a pop rivet gun. 10 Ensure the lever mode switch wiring is correctly routed then reconnect its connector. Where necessary, refit the pawl switch and the ignition key release switch as described in Section 8. 11 Clip the rear heater/ventilation duct back into position then refit the support brackets, tightening their retaining bolt/nuts securely. 12 Refit the centre console as described in Chapter 11. 13 Ensure the pivot bush is correctly positioned then reconnect the linkage rod to the transmission selector lever and secure it in position with the retaining clip. 14 Check the operation of the selector linkage and, if necessary, adjust as described in Section 3 before lower the vehicle to the ground. 6 Oil seals renewal 4 Propeller shaft flange oil seal Note: A new flange sealing ring and retaining nut will be required. 1 Working as described in Chapter 8, free the front end of the propeller shaft from the transmission flange and remove the vibration damper (where fitted). If necessary, to improve access to the flange remove the shaft completely. 2 To prevent the rotation as the shaft nut is slackened bolt a length of bar with two holes drilled in it to the flange. Alternatively, a tool can be fabricated from two lengths of steel strip (one long, one short) and a nut and bolt; the nut and bolt forming the pivot of a forked tool. 3 Hold the flange then slacken and remove the retaining nut from the end of the transmission main shaft. Remove the holding tool and slide off the flange complete with its sealing ring. Discard the nut and sealing ring; new ones should be used on refitting. 4 Note the correct fitted depth of the seal in the transmission housing then carefully prise it out of position using a large flat-bladed screwdriver. 5 Check the propeller flange sealing surface 3510 Vauxhall/Opel Omega for signs of wear or damage. If there is visible signs of damage, renew the flange. 6 Clean all traces of dirt from the area around the oil seal aperture then apply a smear of grease to the outer lip of the new oil seal. 7 Making sure its sealing lip is facing inwards, slide the new seal over the main shaft end and tap it squarely into position, using a suitable tubular drift (such as a socket) which bears only on the hard outer edge of the seal. Ensure the seal is positioned at the same depth in the housing that the original was. 8 Fit the new sealing ring to the flange then lubricate the seal with a smear of transmission oil. Carefully slide the propeller flange into position, taking care not to damage the seal lip. Fit the new nut and tighten it to the specified torque using the method employed on removal to prevent rotation. 9 Reconnect/refit the propeller shaft as described in Chapter 8. 10 Take the vehicle on a short run then check the transmission fluid level as described in Chapter 1. Selector shaft oil seal 11 Remove the selector lever position switch as described in Section 8. 12 Using a small flat-bladed screwdriver, carefully lever the oil seal out from the housing then slide it off of the shaft. 13 Clean all traces of dirt from the area around the oil seal aperture then apply a smear of grease to the outer edge and lip of the new oil seal. 14 Making sure its sealing lip is facing inwards, slide the new seal along the selector shaft and tap it squarely into position, using a suitable tubular drift (such as a socket) which bears only on the hard outer edge of the seal. 15 Refit the selector lever position switch as described in Section 8. 7 Fluid cooler general information 1 The transmission fluid cooler is an integral part of the radiator assembly. Refer to Chapter 3 for removal and refitting details, if the cooler is damaged the complete radiator assembly must be renewed. 8 Transmission control system electrical components removal and refitting 4 Selector lever position switch 1 The switch is a multi-function switch, performing the reversing light and starter inhibitor switch functions as well as operating the selector lever position indicator panel. If at any time the indicator panel or reversing light operation becomes faulty, or it is noted that the engine can be started with the selector Automatic transmission 7B•5 lever in any position other than P (park) or N (neutral), then it is likely that the switch is faulty. If adjustment fails to correct the fault then the switch assembly must be renewed. Removal 2 Position the selector lever in the N (neutral) position. Firmly apply the handbrake then jack up the rear of the vehicle and support it on axle stands. 3 Referring to Chapter 4A, slacken and remove the bolts securing the front pipe/ catalytic converter to the intermediate pipe and separate the flange joint; on 2.5 and 3.0 litre models disconnect both left- and right-hand sides. Unbolt the heatshield(s) from the vehicle underbody to gain access to the propeller shaft centre bearing. 4 Slacken and remove the two bolts securing the propeller shaft centre bearing bracket to the vehicle body (see Chapter 8). Recover any washers (where fitted) which are positioned between the bracket and vehicle body. 5 Trace the wiring back from the switch and disconnect it at the wiring connector. Unclip the wiring connector from the side of the transmission housing so that it is free to be removed with the switch. If the connector retaining clip is broken on removal, obtain a new one for refitting. 6 Unclip the protective cover from the switch then unscrew the retaining nut and free the selector lever from the end of the transmission shaft (see illustrations). 7 Place a jack with a block of wood beneath the transmission, and raise the jack to take the weight of the transmission. 8 With the transmission securely supported, slacken and remove the bolts securing the transmission unit rear mounting crossmember to the vehicle body. 9 Lower the transmission slightly until access can be gained to the switch retaining bolts. As the transmission is lowered, take great care to ensure excess strain is not placed on the propeller shaft or any of the engine components and enlist the help of an assistant to make sure nothing becomes trapped between the rear of the engine and bulkhead. Note: On 2.0 litre SOHC engines it maybe necessary to remove the DIS module assembly to gain the necessary clearance required (see Chapter 5B). 10 Slacken and remove the retaining bolts and slide the switch off of the selector shaft. Whilst the switch is removed check the shaft oil seal for signs of leakage and renew if necessary (see Section 6). Refitting 11 Prior to refitting, first make sure that the transmission selector shaft is still in the N (neutral) position. If there is any doubt, engage the selector lever with the transmission shaft and move the lever fully backwards (to the P position) then move it two notches forwards. 12 If a new switch is being fitted, locate the switch on the shaft then refit the retaining 8.6a Unclip the protective cover from the position switch . . . 8.6b . . . then slacken and remove the retaining nut (arrowed) and free the selector lever from the shaft bolts, tightening them to the specified torque. Note that it is not necessary to adjust the switch since it is set at the factory and sealed in position; the seal will be broken the first time the selector lever is moved. 13 If the original switch is being refitting, locate the switch on the transmission shaft then refit the retaining bolts. Adjust the switch as described in paragraph 21 before tightening the retaining bolts to the specified torque. 14 Reconnect the selector lever to the transmission shaft then refit the retaining nut. Tighten the nut to the specified torque setting then clip the protective cover back onto the switch. 15 Securely reconnect the wiring connector then clip the switch connector back onto the transmission unit and raise the transmission unit back up into position. 16 Remove all traces of locking compound from the transmission unit rear mounting crossmember to body bolt threads. Apply a few drops of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of each bolt then refit the bolts and tighten to the specified torque. 17 Align the propeller shaft centre bearing bracket with the body making sure any necessary washers (where fitted) are positioned between the bracket and body. Refit the bracket retaining bolts and tighten to the specified torque. 18 Referring to Chapter 4A, refit the heatshields and reconnect the exhaust system flange joint(s) then lower the vehicle to the ground. 21 With the transmission in neutral, the slot on the switch body should be correctly aligned with the slot on the switch inner ring. Check this by inserting the welding rod (see illustration). If adjustment is necessary, slacken the switch retaining bolts and rotate the switch assembly as necessary before retightening the bolts to the specified torque setting. 22 Refit the selector lever to the shaft and tighten its retaining nut to the specified torque. 23 Clip the protective cover back onto the switch then lower the vehicle to the ground. Sport mode switch Note: A soldering iron and solder will be required to renew the switch. Removal 24 Unclip the selector lever gaiter from the centre console. 25 Push the switch out of the top of the selector lever by inserting a length of welding rod up through the selector lever bore. 26 Make identification marks between the switch and wires then carefully unsolder the wires from the switch terminals and remove the switch. Refitting 27 Solder the wires to the terminals of the switch, using the marks made prior to removal to ensure they are correctly connected. 7B Adjustment Note: Before adjusting the switch first ensure the selector linkage is correctly adjusted (see Section 3). A short length of welding rod with a diameter of 2.0 to 2.3 mm will be required for adjustment. 19 Position the selector lever in the N (neutral) position. Firmly apply the handbrake then jack up the rear of the vehicle and support it on axle stands. 20 Unclip the protective cover from the switch then unscrew the retaining nut and free the selector lever from the end of the transmission shaft. 3510 Vauxhall/Opel Omega 8.21 Adjusting the selector lever position switch 1 Switch retaining bolts 2 Switch grooves 3 Welding rod 7B•6 Automatic transmission connector then carefully free the ignition key switch wiring from the rear of the connector. Disconnect the switch earth lead from the lever mounting plate. 43 Prise off the retaining clips and remove the switch from the vehicle (see illustration). Refitting 44 Refitting is the reverse of removal using new retaining clips. Electronic control unit (ECU) Removal 8.30 Removing the winter mode switch panel from the centre console 8.35 Selector lever pawl switch later models 28 Push the switch securely into position then clip the selector lever gaiter back onto the console. Winter mode switch from the around the selector lever. 35 Disconnect the wiring connectors then prise off the retaining clips and remove the switch from the selector lever mounting plate (see illustration). Removal Refitting 29 Unclip the selector lever gaiter from the centre console. 30 Reach in behind the console and push the switch panel out of position, disconnecting its wiring connector as it becomes accessible (see illustration). The switch and panel can then be separated. 36 Refitting is the reverse of removal ensuring the switch is securely retained by the new clips. Refitting 37 Remove the selector lever as described in Section 5 (see illustration). 38 Disconnect the solenoid earth lead from the lever mounting plate and carefully free the solenoid wiring from the main wiring connector. 39 Undo the retaining screws and remove the solenoid from the lever mounting plate. 31 Refitting is the reverse of removal ensuring the wiring is correctly routed. Kickdown switch 32 The kickdown switch is an integral part of the accelerator cable and cannot be renewed separately. Refer to Chapter 4A for details of accelerator cable removal and refitting. Selector lever pawl contact switch - later models Note: New switch retaining clips should be used on refitting. Removal Selector lever pawl starter solenoid - later models Removal Refitting 40 Refitting is the reverse of removal making sure the solenoid is correctly engaged with the pawl. Ignition key release contact switch - later models 45 The ECU is located behind the right-hand side of the facia. Prior to removal, disconnect the battery negative terminal. 46 On right-hand drive models, release the retaining clips (rotate them through 90º) then remove the undercover panel from the drivers’ side of the facia. Remove the fastener (prise out the centre pin then pull out the fastener outer section) then unclip and remove the heater/ventilation duct. 47 On left-hand drive models remove the glovebox (see Chapter 11). 48 On all models, unscrew the retaining nuts securing the ECU to the pillar then carefully lower the ECU out of position. Release the retaining clip and disconnect the wiring connector then remove the ECU from the vehicle. Refitting 49 Refitting is the reverse of removal ensuring that the wiring is securely reconnected. If a brand new ECU has been fitted it will be necessary to take the vehicle to a Vauxhall dealer to have the unit coded to match the performance of the relevant engine fitted to your vehicle. Transmission output shaft speed sensor Removal 33 Remove the centre console as described in Chapter 11 then position the selector lever in the P (park) position. 34 Slacken and remove the retaining nuts and bolt then remove the front and rear support brackets from the rear heater/ ventilation duct. Unclip the duct and remove it Note: New switch retaining clips should be used on refitting. 41 Carry out the operations described in paragraphs 33 and 34. 42 Disconnect the selector lever main wiring 50 The output shaft speed sensor is fitted to the rear of the transmission unit where it is located above and to the left off the propeller shaft flange (see illustration). 51 To gain access to the sensor, firmly apply the handbrake then jack up the front of the vehicle and support it on axle stands. 52 Disconnect the wiring connector and wipe 8.37 Selector lever pawl starter solenoid later models 8.43 Ignition key release contact switch later models 8.50 Transmission output shaft speed sensor location Removal 3510 Vauxhall/Opel Omega Automatic transmission 7B•7 9.3 Slide off the retaining clip and detach the selector linkage rod from the transmission clean the area around the sensor. 53 Undo the retaining bolt and remove the sensor from the transmission. Remove the sealing ring from the sensor and discard it, a new one should be used on refitting. Refitting 54 Fit the new sealing ring to the sensor groove and lubricate it with a smear of transmission fluid. 55 Ease the sensor into position then refit the retaining bolt and tighten it to the specified torque setting. Reconnect the wiring connector then lower the vehicle to the ground. Transmission solenoid valves 56 Removal and refitting of the various solenoid valves should be entrusted to a Vauxhall dealer. 9 Automatic transmission removal and refitting 4 Removal 1 Chock the rear wheels, apply the handbrake, and place the selector lever in the N (neutral) position. Jack up the front of the vehicle, and securely support it on axle stands. Undo the retaining screws and remove the undercover from beneath the engine unit. Disconnect the battery negative terminal. Note: On models with a Vauxhall anti-theft warning system (ATWS), the battery negative terminal must be disconnected within 15 seconds of the ignition being switched off to prevent the alarm system being triggered. 2 Working as described in Chapter 8, unbolt the front end of the propeller shaft from the transmission flange and remove the vibration damper (where fitted). Position the propeller shaft to the right of the transmission unit and tie it to the vehicle underbody. 3 Slide off the retaining clips and detach the selector linkage rod from the transmission unit and selector lever and remove it from the vehicle (see illustration). Take care not to lose the lever pivot bushes. 4 Trace the fluid cooler pipes back from the transmission unit to their flexible hoses. 9.4a Release the retaining clips and disconnect the oil cooler pipes . . . 9.4b . . . then fold them back and connect them as shown to minimise fluid loss Remove all traces of dirt then slacken the retaining clips and disconnect both hoses. Minimise fluid loss by folding each hose back on itself and securely connecting it to its adjacent pipe (see illustrations). 5 Disconnect the wiring connector from the output shaft speed sensor (see illustration 8.50), which is located at the rear of the transmission unit, and free the wiring from the transmission unit. 6 On SOHC engines, disconnect the wiring connector from the DIS module (see Chapter 5B). Slacken and remove the module mounting bracket retaining bolts, noting the correct fitted location of the engine lifting bracket, then free the wiring harness and remove the module and bracket from the rear of the cylinder head. Free the HT leads from their retaining clips and position the assembly clear of the transmission unit. 7 On all models unclip the oxygen sensor wiring connector from transmission unit and disconnect it. 8 Slacken and remove the exhaust system front pipe mounting bracket bolt then remove the bolts securing the front pipe to the intermediate pipe and separate the two exhaust sections. 9 On models with a one-piece engine sump, slacken and remove the bolts securing the support brackets to the transmission housing and sides of the cylinder block. Remove both brackets from the engine then remove the torque converter lower cover plate from the base of the transmission housing. 10 On models with a two-piece engine sump, remove the cover from the sump flange to gain access to the torque converter to driveplate bolts. 11 Slacken and remove the visible bolt(s) then, using a socket and extension bar to rotate the crankshaft pulley, undo the remaining bolts securing the torque converter to the driveplate as they become accessible; there are six bolts in total. If necessary, to prevent rotation as the bolts are slackened, remove the cover from the base of the torque converter housing and retain the driveplate by inserting a large screwdriver in through the hole. 12 Place a jack with a block of wood beneath the transmission, and raise the jack to take the weight of the transmission (see illustration). 13 With the transmission securely supported, slacken and remove the bolts securing the transmission unit rear mounting crossmember to the vehicle body (see illustration). 14 Lower the transmission unit slightly and disconnect the vent hose from the top of the transmission housing. 15 Trace the wiring back from the selector lever position switch and disconnect it at the wiring connector. Unclip the wiring connector and position it clear of the transmission housing; if the connector retaining clip is broken on removal, obtain a new one for refitting. 16 Release the retaining clips and disconnect the wiring connectors from the side of the transmission main and intermediate housings (see illustration). Release all the wiring from its retaining clips, noting its correct routing, and position it clear of the transmission unit. 9.12 Securely support the transmission unit with a suitable jack . . . 9.13 . . . then slacken and remove the bolts securing the transmission unit crossmember to the body 2.0 litre engines 3510 Vauxhall/Opel Omega 7B 7B•8 Automatic transmission 9.16 Disconnect the wiring connectors from the transmission unit and free the wiring from its retaining clips 17 Slacken and remove all the bolts securing the transmission housing to the engine. Note the correct fitted positions of each bolt, and the necessary brackets, as they are removed, to use as a reference on refitting. Make a final check that all components have been disconnected, and are positioned clear of the transmission so that they will not hinder the removal procedure. 18 To ensure that the torque converter does not fall out as the transmission is removed, slide the converter along the shaft and fully into the transmission housing. 19 Move the trolley jack and transmission to the rear, to free it from its locating dowels. Once the transmission is free, carefully lower the jack and manoeuvre the unit out from under the vehicle. Remove the locating dowels from the transmission or engine if they are loose, and keep them in a safe place. 2.5 and 3.0 litre models 20 Remove both the exhaust system front pipes as described in Chapter 4A. 21 Remove the cover from the sump flange to gain access to the torque converter retaining bolts. Slacken and remove the visible bolt then, using a socket and extension bar to rotate the crankshaft pulley, undo the remaining bolts securing the torque converter to the driveplate as they become accessible; there are six bolts in total. If necessary, to prevent rotation as the bolts are slackened, remove the cover from the base of the torque converter housing and retain the driveplate by inserting a large screwdriver in through the hole (see illustrations). 9.21c If necessary, the driveplate can be retained by removing the cover and inserting a large screwdriver in through the hole 9.21a Prise out the cover from the sump flange . . . 22 Remove the transmission as described in paragraphs 12 to 19. Refitting 23 The transmission is refitted by a reversal of the removal procedure, bearing in mind the following points. a) If a new transmission unit is being installed, drain the fluid cooler and blow out the cooler lines using low-pressure compressed air. b) Check the torque converter centering pin and the crankshaft bush for signs of wear or damage. Remove all traces of dirt and rust then lubricate the bush a pin with a thin smear of molybdenum disulphide grease (Vauxhall recommend the use of lubricating grease 19 48 568 - available from your Vauxhall dealer). c) Prior to refitting, ensure that the torque converter is correctly engaged with the transmission by measuring the distance from the converter driveplate bolt lugs to the transmission mating surface. This should be 15 mm (see illustration). d) Ensure the locating dowels are correctly positioned and take great care not to allow the weight of the unit to hang on the torque converter as it is installed. Once the transmission and engine are correctly joined, refit the securing bolts, tightening them to the specified torque setting. e) Align the torque converter with the driveplate then refit the retaining bolts tightening them lightly only to start then go around and tighten them to the specified torque setting in a diagonal sequence. f) Ensure that the transmission wiring/hoses are correctly routed and retained by all the necessary clips. g) Remove all traces of locking compound from the transmission unit rear mounting crossmember to body bolt threads. Apply a few drops of thread locking compound (Vauxhall recommend the use of locking compound 15 10 181 - available from your Vauxhall dealer) to the threads of each bolt prior to refitting and tighten both bolts to the specified torque. h) Tighten all nuts and bolts to the specified torque (where given). 3510 Vauxhall/Opel Omega 9.21b . . . then slacken and remove the torque converter to driveplate bolts as described in text i) On completion, refill the transmission with the specified type and quantity of fluid as described in Section 2 and adjust the selector linkage as described in Section 3. 10 Automatic transmission overhaul general information 5 1 Overhaul of an automatic transmission unit is beyond the scope of the home mechanic and should be entrusted to a transmission specialist. 2 In the event of a fault occurring with the transmission, the vehicle should be taken to a suitably-equipped Vauxhall dealer for testing. A wiring block connector is incorporated in the electronic control circuit, into which a special electronic diagnostic tester can be plugged (see Section 1) and this should locate the fault. 3 Do not remove the transmission from the car for possible repair before professional fault diagnosis has been carried out, since most tests require the transmission to be in the vehicle. 9.23 Check the torque converter is fully engaged by measuring the distance (X) from the converter bolt lugs to the transmission surface. This should be 15 mm 8•1 Chapter 8 Final drive, driveshafts and propeller shaft Contents Driveshaft - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . Driveshaft rubber gaiters and outer constant velocity joint - renewal Final drive unit - oil level check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final drive unit - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . Final drive unit damping bracket - renewal . . . . . . . . . . . . . . . . . . . . Final drive unit differential bearing oil seal - renewal . . . . . . . . . . . . . 8 9 3 2 4 7 Final drive unit pinion oil seal - renewal . . . . . . . . . . . . . . . . . . . . . . . 6 Final drive unit rear cover gasket - renewal . . . . . . . . . . . . . . . . . . . . 5 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Propeller shaft - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 10 Propeller shaft centre bearing - renewal . . . . . . . . . . . . . . . . . . . . . . 11 Propeller shaft disc joints - renewal . . . . . . . . . . . . . . . . . . . . . . . . . 12 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications Final drive Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final drive ratio: Up to 1998 model year: All 2.0 litre 4-cylinder models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 litre 6-cylinder models: Manual transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre 6-cylinder models: Manual transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . From 1998 model year: All 2.0 litre 4-cylinder models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 litre 6-cylinder models: Manual transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litre 6-cylinder models: Manual transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Limited slip differential lock-up value: Typical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Minimum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Unsprung, attached to rear suspension crossmember and underbody. Limited slip differential optional. 3.90 : 1 3.70 : 1 3.90 : 1 3.70 : 1 3.70 : 1 3.90 : 1 3.90 : 1 4.22 : 1 3.70 : 1 3.90 : 1 45 % 25 % Driveshaft Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maintenance-free double constant velocity joint Propeller shaft Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Two-piece tubular shaft with centre bearing, centre universal joint, and flexible disc joint connections to transmission and differential Lubrication Final drive lubricant capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final drive lubricant type/specification: Excluding limited-slip differential: Renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Top-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Limited-slip differential: Renewal: First 0.25 litres . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Remaining 0.75 litres . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Top-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Driveshaft CV joint grease type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 litre GM special lubricant 19 42 382 (9 293 688) Hypoid gear oil, viscosity SAE 90 GM special fluid additive 19 70 452 (90 004 033) GM special lubricant 19 42 382 (9 293 688) GM special lubricant 19 42 382 (9 293 688) GM special grease 19 41 522 (90 007 999) 3510 Vauxhall/Opel Omega 8 8•2 Final drive, driveshafts and propeller shaft Torque wrench settings Damping bracket to final drive unit*: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disc joint to propeller shaft transmission or differential: Hexagon bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torx bolt*: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Driveshaft to hub: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final drive oil level check plug: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final drive unit damping bracket bush to rear crossmember*: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final drive unit rear cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Final drive unit to crossmember*: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Propeller shaft centre bearing bracket to underbody . . . . . . . . . . . . . . . Propeller shaft centre bearing to bracket . . . . . . . . . . . . . . . . . . . . . . . . Propeller shaft to flexible joint: Hexagon bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torx bolt*: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Speed sensor to bracket (with ABS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . *Indicates that a new bolt/nut must be used. 1 General description 1 The final drive unit houses the differential gears and is bolted directly to the rear suspension crossmember. The unit has a cast aluminium casing which incorporates external ribs to improve structural rigidity and fluid cooling. A bracket with an integral rubber damping block bolted between the final drive casing and the suspension crossmember controls the movement of the final drive during operation. 2 A limited-slip differential may be fitted as an option; this incorporates a clutch mechanism which controls the difference in speed between the left and right hand driveshafts. Under normal conditions, the clutch slips allowing the driveshafts to rotate at different speeds, such as during cornering. When the speed differential increases beyond a preset limit, such as during wheelspin caused by rapid acceleration or poor road surfaces, the clutch locks thus preventing the differential from supplying all available drive to the spinning wheel, and ensuring equal distribution of drive to both rear wheels. Nm lbf ft 90 Tighten a further 45º Tighten a further 15º 66 95 70 50 Tighten a further 75º Tighten a further 15º 37 50 Tighten a further 60º Tighten a further 15º 37 22 Tighten a further 90º Tighten a further 180º 16 100 Tighten a further 75º Tighten a further 15º 60 74 44 90 Tighten a further 30º Tighten a further 15º 20 22 15 16 95 70 50 Tighten a further 45º Tighten a further 15º 4 37 3 Two driveshafts, incorporating Rzeppa-type constant velocity joints, transmit drive from the final drive differential to the rear wheels. The inner joints incorporates the Anti-lock Braking System (ABS) rear wheel sensor reluctor discs - see Chapter 9 for details. Flexible rubber gaiters filled with grease encapsulate each joint, keeping the joint lubricated and preventing the ingress of dirt and debris. 4 A two-piece, tubular propeller shaft transmits drive from the transmission from to the final drive unit. It incorporates a centre 66 3 bearing supported in a rubber insulator. The rear section of the shaft has a universal joint at its front end, and the front section has a slider joint at its rear end. The propeller shaft is secured to the transmission and differential by flexible disc joints. Final drive identification 5 The type of final drive unit fitted can be determined by examining the identification plate affixed to the underside of the final drive unit (see illustration). 2 Final drive unit removal and refitting 3 Removal 1.5 Final drive unit identification plate 1 Limited slip differential (0 = yes, 1 = no) 2 Final drive ratio 3510 Vauxhall/Opel Omega 1 Chock the front wheels securely. Jack up the rear of the vehicle, support it on axle stands and remove both rear wheels. 2 Remove both driveshafts with reference to Section 8. 3 Unhook the exhaust system mounting rubbers and lower the rear of the system approximately 300 mm (12.0 in). Support or tie the system in this position. Final drive, driveshafts and propeller shaft 8•3 4 Unbolt the propeller shaft rear flange from the flexible drive joint and lever the propeller shaft from the joint. Support the propeller shaft on an axle stand - do not let it hang by the universal joint. 5 Position a trolley jack underneath the final drive unit, and raise it until it just comes into contact with the underside of the casing. 6 Unplug the wiring from both ABS wheel sensors at the connectors. 7 Unscrew the bolt securing the damping bracket at the front of the final drive casing to the suspension crossmember. 8 Unscrew and withdraw the bolt securing the rear of the final drive casing to the suspension crossmember. 9 Lower the trolley jack and remove the final drive from the underside of the vehicle. Refitting 10 Refitting is a reversal of removal, noting the following points:. a) Check that the distance between the two final drive bushes on the suspension crossmember is between 300 and 302 mm. If necessary, adjust this dimension by altering the position of the bushes in the crossmember, using a universal puller or similar tool. b) Ensure that the wiring for the ABS wheel sensors is securely reconnected. c) Use new bolts/nuts where indicated (see Specifications) and tighten all fixings to the specified torque. d) Refit the driveshafts with reference to Section 8. e) On completion, check the oil level in the final drive unit as described in Section 3. 3 Final drive unit oil level check 2 Level check 1 Jack up the front and rear of the vehicle and support it on axle stands so that the vehicle is level. 2 Using a hexagon key, unscrew the filler plug from the right-hand side of the final drive unit. On models with a limited slip differential, it will be necessary to prise the bung from the centre of the plug first (see illustration). 3 Check that the oil level is up to the lower edge of the filler plug aperture using a (clean) piece of bent wire as a dipstick. 4 If necessary, top-up with the correct type of oil as given in the Specifications. 5 Refit and tighten the filler plug to the specified torque, and wipe clean. Refit the plastic bung to the centre of the plug on models with a limited slip differential. 6 Check the pinion final drive unit oil seal and differential bearing oil seals for leaks. If evident, renew them. 7 Lower the car to the ground. 3.2 Final drive unit oil filler/level plug (A) and plastic bung (B) Complete refill 8 Proceed as described for Level check noting the following points:. a) On models without a limited slip differential, GM special differential oil must be used if the final drive is being refilled from empty, rather than just topped-up (see Specifications). b) On models with a limited slip differential, if the final drive is being refilled from empty, rather than just topped-up, the procedure must be carried out in two stages: 1) Pour 0.25 litres of GM special differential oil additive into the final drive 2) Pour approximately 0.75 litres of GM special differential oil into the final drive, until the level reaches the lower edge of the filler plug aperture (see Specifications). 4 Final drive unit damping bushes renewal suspension crossmember. Lower the final drive unit slightly, using the trolley jack. 6 Slacken and withdraw the three bolts securing the damping bracket to the final drive unit casing. Be prepared for some oil leakage - position a drip tray underneath the final drive casing to catch the oil. 7 Detach the damping bush bracket from the final drive casing and remove it from the vehicle. Withdraw the securing bolt from the damper bush. 8 Press the old bush from the bracket using a hydraulic press, or drive it out using a suitable drift. Drive or press the new bush into position, ensuring that the recessed section of the bush is correctly aligned with the bracket boss (see illustration). 9 Commence refitting by inserting the securing bolt through the centre of the damper bush. 3 8 Front bush 1 Chock the front wheels. Jack up the rear of the vehicle and support it on axle stands. 2 Support the final drive unit on a trolley jack. 3 Unplug the wiring from both ABS wheel sensors at the connectors. 4 Slacken and withdraw the bolts securing the rear of the final drive unit to the suspension crossmember. 5 Fully unscrew the bolt securing the damping bush bracket to the front of the 3510 Vauxhall/Opel Omega 4.8 Ensuring that the recessed section of the bush is aligned with the bracket boss as shown 8•4 Final drive, driveshafts and propeller shaft 4.19 Press the new bushes into the crossmember, ensuring that the distance measured between their inner edges (I) is between 300 and 302 mm 10 Offer the bracket, bush and securing bolt up to the final drive casing. Insert the three bracket securing bolts and tighten them to the specified torque. 11 Raise the final drive casing up into position using the trolley jack, then tighten the damper bush-to-suspension crossmember bolt and tighten it to the specified torque. 12 Refit the two rear final drive casing-tosuspension crossmember bolts and tighten them to the specified torque. 13 Reconnect the wiring for the ABS wheel sensors. 14 On completion, top-up the differential oil with reference to Section 3, then lower the vehicle to the ground. Rear bushes 15 Remove the final drive unit as described in Section 2. 16 Unbolt the fuel filter from its mountings and move to one side, with reference to Chapter 1. There should be no need to disconnect the fuel lines from it. 17 With reference to Chapter 4A, unhook the exhaust system intermediate silencer from its mountings and support it on axle stand. 18 Extract the bushes from the suspension crossmember using a universal puller or similar tool. The bushes are removed from the outside of the crossmember. 19 Press the new bushes into the crossmember, ensuring that the distance measured between their inner edges is between 300 and 302 mm (see illustration). 20 Refit the final drive unit as described in Section 2. 21 Refit the fuel filter and exhaust system silencer as described in Chapters 1 and 4A respectively. 5 Final drive unit rear cover gasket renewal 3 1 Remove the final drive unit as described in Section 2. 2 Place the final drive unit in a suitable drip tray, then unbolt and remove the rear cover from the casing. Remove the gasket and allow the oil to drain. 3 Thoroughly clean the joint faces of the final drive casing and cover. 4 Apply a coat of the recommended sealant to the mating surface of the final drive casing. 5 Refit the cover, then insert and tighten the bolts progressively to the specified torque. It is recommended that new bolts are used. 6 Refit the final drive unit to the vehicle as described in Section 2. 7 Lower the vehicle to the ground. On completion, refill the final drive unit with the specified quantity and grade(s) of oil, as described in Section 3. 6 Final drive unit pinion oil seal - renewal 7 Final drive unit differential bearing oil seal renewal 3 1 Chock the front wheels. Jack up the rear of the vehicle and support it on axle stands. Remove the appropriate rear wheel. 2 Remove the appropriate driveshaft with reference to Section 8. 3 Note the fitted depth of the oil seal in the final drive casing. 4 Using a screwdriver or hooked instrument, lever out the oil seal (see illustration), taking 3 Caution: The pinion bearing pre-load will be affected by the renewal of the pinion oil seal and must be reset accurately following repair work. The following procedure describes how to reset the bearing pre-load approximately, using rudimentary tools, but we recommend that the pre-load is set accurately by a Vauxhall dealer, or an engineering workshop. 1 Remove the final drive unit as described in Section 2. 3510 Vauxhall/Opel Omega 2 Mount the unit in a vice. 3 Measure the pinion bearing pre-load as follows: fit a socket on the pinion nut, and using an adjustable low-torque wrench, measure the torque which must be applied to cause pinion to just start to rotate - the figure should be approximately 90 to 120 Ncm. Record this figure for later reference. 4 Mark the drive flange nut in relation to the drive flange and pinion. 5 Hold the drive flange stationary by bolting a length of metal bar to it, then unscrew the nut noting the exact number of turns necessary to remove it. 6 Using a suitable puller, draw the drive flange from the pinion. 7 Lever the oil seal from the final drive casing with a screwdriver. Wipe clean the oil seal seating. 8 Smear a little differential oil (see Specifications) on the sealing lip of the new oil seal, then drive it squarely into the casing until flush with the outer face. Ideally use metal tubing to fit the oil seal, but alternatively a block of wood may be used on each side of the pinion. 9 Locate the drive flange on the pinion in its original position, then refit the nut to its original position, using the markings and notes made during removal. 10 The pinion drive bearing pre-load must now be reset to its original value. Measure the torque required to turn the pinion, as described in paragraph 3. Adjust the position of the pinion nut until the measured value is the same as that recorded earlier. 11 Refit the final drive unit with reference to Section 2. 7.4 Differential bearing oil seal Final drive, driveshafts and propeller shaft 8•5 great care avoid damaging the surface of the seal housing. Wipe the oil from the oil seal housing. 5 Smear a little oil on the sealing lip of the new oil seal. Using suitable metal tubing drive the oil seal squarely into the casing to the previously noted position. 6 Refit the driveshaft with reference to Section 8. 7 Refit the wheel and lower the vehicle to the ground. 8 Driveshaft removal and refitting 3 Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support it on axle stands. 2 Unscrew the socket-head bolts securing the driveshaft to the rear hub while holding the rear wheel stationary. Recover the lockwashers. 3 Lever the driveshaft from the rear hub and support it above the disc brake assembly. 4 Remove the rear wheel. 5 Position a container under the final drive unit to catch any spilled oil. 6 Carefully lever the driveshaft from the final drive unit differential. On models with anti-lock braking take care not to damage the wheel speed sensor and reluctor wheel. 7 Withdraw the driveshaft from the side of the vehicle. 8 Check the circlip on the inner end of the driveshaft and if necessary renew it. Refitting 9 Refitting is a reversal of removal, but make sure that the driveshaft is fully entered in the differential side gear with the circlip engaged in its groove. Tighten the mounting bolts in three stages, as detailed in the Specifications (see illustrations). Check and if necessary top up the oil level in the final drive unit, as described in Section 3. 8.9a Tighten the driveshaft mounting bolts to the specified first stage torque . . . 9 Driveshaft rubber gaiters and outer constant velocity joint - renewal 3 1 Remove the driveshaft as described in Section 8 and mount it in a vice. 2 Using a small drift, tap the metal cover from the outer joint. 3 Loosen and remove both clips from the rubber bellows. 4 Using a sharp knife slice through the rubber bellows and remove them from the driveshaft. 5 Scoop out the grease from the joint and wipe the driveshaft clean. 6 Using circlip pliers, extract the circlip from the outer end of the driveshaft. 7 Support the outer joint on a vice, then tap the driveshaft down through it. 8 Fill the inner joint with the specified type of grease using a wooden spatula. 9 Fit the new inner bellows, check that it is not twisted then fit and tighten the clips. 10 Locate the outer bellows on the driveshaft. 11 Fit the outer joint, using a tubular metal drift, with the driveshaft mounted in a vice. Make sure that the joint abuts the shoulder. 12 Fit the circlip making sure that it fully enters the groove. 13 Using the wooden spatula fill the outer joint with grease. 14 Locate the outer bellows on the plate, check that it is not twisted then fit and tighten the clips. 8.9b . . . then angle tighten to the specified second and third stages 15 Locate the cover on the joint using two driveshaft bolts to ensure correct alignment. Tap the cover on the joint with a soft-faced mallet. 16 Extract the retaining circlip from the inner end of the driveshaft and fit a new one. 17 Refit the driveshaft with reference to Section 8. 10 Propeller shaft removal and refitting 3 Removal 1 Chock the front wheels. Jack up the rear of the vehicle and support it on axle stands. 2 On models equipped with a catalytic converter, from underneath the vehicle, undo the retaining bolts and remove both the large and small catalytic converter heatshields from the vehicle underbody (see illustration). 3 At the sliding joint, mark the relationship between the front and rear sections of the propeller shaft. If the two halves of the shaft become separated during removal, reconnect them using the alignment markings, to preserve the balance characteristics. 4 Using a conventional, or Torx, socket as applicable, unscrew the bolts securing the front flexible disc joint to the transmission output flange (see illustration). 5 At the rear of the propeller shaft, unscrew the bolts securing the rear disc joint to the differential flange (see illustration). 8 10.2 Remove the exhaust heat shields from the vehicle underbody 10.4 Unscrew the bolts (arrowed) securing the front flexible disc joint to the transmission output flange 3510 Vauxhall/Opel Omega 10.5 Unscrew the bolts (arrowed) securing the rear disc joint to the differential flange 8•6 Final drive, driveshafts and propeller shaft 3 11 Propeller shaft centre bearing renewal 10.6 Centre bearing support bracket bolts (arrowed) 6 Support the centre of the propeller shaft on an axle stand, then unbolt the centre bearing support bracket from the underbody, noting the location of any alignment shims (see illustration). 7 Push the front section rearwards along the slider joint splines until clear of the transmission output flange. 8 Withdraw the propeller shaft forwards, making sure that the front section remains on the slider joint splines (see paragraph 3). 9 Unbolt the centre support bracket from the centre bearing, noting the location of any alignment shims. 10 Unbolt the front and rear disc joints from the propeller shaft. Note that on some models a vibration damper is fitted at the front of the propeller shaft. Refitting 11 Refitting is a reversal of removal, noting the following points:. a) Coat the inboard splines of the driveshaft with differential oil before inserting them into the final drive. b) Tighten all nuts and bolts to the specified torque. 1 Remove the propeller shaft as described in Section 10. 2 Mount the rear propeller shaft section in a vice, using shaped blocks of wood to prevent damage. 3 Mark the front and rear sections in relation to each other, then pull the front section from the splines. 4 Slide off the rubber sleeve, then using circlip pliers, extract the circlip from the groove in front of the centre bearing (see illustration). Extract the dust seal washer. 5 Unbolt the centre bearing from its mounting bracket. 6 Support the centre bearing on a vice, and press or drive the rear propeller shaft section down through the bearing. Recover the dust seal washer. 7 Similarly, press or drive the ball bearing from the centre bearing housing, and remove the dust cover. 8 Clean the removed components and the end of the propeller shaft. Lightly grease the splines. 9 Press or drive the new ball bearing into the housing, and align the dust washer. 10 Support the rear section universal joint on a vice, and press or drive the centre bearing over the splines using a metal tube on the inner track. Make sure that the bearing makes contact with its seating shoulder. 11 Bolt the mounting bracket to the centre bearing and tighten the bolts to the specified torque. 12 Mount the rear section in a vice, and fit the front dust washer and the circlip, making sure that it is correctly located in the groove. 13 Locate the rubber sleeve over the splines. 14 Fit the front section on the rear section 11.4 Extract the circlip from the groove in front of the centre bearing splines, making sure that the previously-made marks are aligned, to preserve the balance characteristics. Note that a master spline is provided to ensure correct assembly (see illustration). 15 Refit the propeller shaft as described in Section 10. 12 Propeller shaft disc joints renewal 3 1 Chock the front wheels. Jack up the rear of the vehicle and support it on axle stands. 2 Apply the handbrake, then where applicable, unbolt and remove the heatshields from the vehicle underbody to gain access to the disc joints. 3 If removing the rear disc joint, unbolt the propeller shaft centre bearing mounting bracket from the underside of the vehicle and support the propeller shaft on an axle stand. 4 Unbolt the propeller shaft flange(s) from the flexible disc joint(s). 5 Unbolt the flexible disc joint from the transmission and/or differential drive flange(s). 6 Push the appropriate propeller shaft section towards the centre bearing and remove the disc joint(s). If necessary, use a lever to prise the propeller shaft clear of the drive flange(s). 7 Fit the new flexible disc joint(s) using a reversal of the removal procedure, noting the following points:. a) Bolt the disc joint to the propeller first, then to the transmission/final drive flange. b) Tighten all nuts and bolts to the specified torque (see Specifications). c) Where applicable, refit the propeller shaft centre bearing mounting bracket to the underside of the vehicle as described in Section 11. d) Securely refit all heatshield panels removed for access. 11.14 Note that a master spline (arrowed) is provided to ensure correct assembly 3510 Vauxhall/Opel Omega 9•1 Chapter 9 Braking system Contents Anti-lock Braking System/Traction Control system (ABS/TC) component removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Anti-lock Braking System/Traction Control system (ABS/TC) information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Brake disc - inspection, removal and refitting . . . . . . . . . . . . . . . . . . 6 Brake fluid reservoir and level sensor - removal and refitting . . . . . . 11 Brake pedal - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Front brake caliper - removal, overhaul and refitting . . . . . . . . . . . . . 4 Front brake pads - inspection, removal and refitting . . . . . . . . . . . . 2 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Handbrake cable - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 8 Handbrake lever - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 9 Handbrake shoes - inspection and renewal . . . . . . . . . . . . . . . . . . . 7 Hydraulic brake lines and hoses - removal and refitting . . . . . . . . . . 13 Hydraulic system - bleeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Master cylinder - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 10 Rear brake caliper - removal, overhaul and refitting . . . . . . . . . . . . . 5 Rear brake pads - inspection, removal and refitting . . . . . . . . . . . . . 3 Vacuum servo hose and non-return valve - renewal . . . . . . . . . . . . . 14 Vacuum servo unit - testing, removal and refitting . . . . . . . . . . . . . . 15 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications General System type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Servo diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Servo piston rod, adjustment length . . . . . . . . . . . . . . . . . . . . . . . . . . . Brake fluid capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Brake pedal travel to illuminate brake lights . . . . . . . . . . . . . . . . . . . . . . Master cylinder, nominal diameter: Up to 1998 model year: 4 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . From 1998 model year: All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front and rear discs, floating front caliper, fixed rear caliper, tandem master cylinder with hydraulic system split front/rear, vacuum servo unit, rear brake proportioning valve on certain models. Electronic anti-lock braking system (ABS) on all models. Cable-operated handbrake to shoes bearing on drums incorporated into rear discs. 200/225 mm 106 + 0.5 mm 0.5 litre (approx.) 15 ± 5 mm 23.81/20.64 mm 25.40/20.64 mm 25.40 mm Front brakes Disc diameter: Up to 1998 model year: 4 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . From 1998 model year: All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disc thickness (new): Up to 1998 model year: 4 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . From 1998 model year: All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disc thickness (minimum, after machining*): Up to 1998 model year: 4 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . From 1998 model year: All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 mm 296 mm 296 mm 24 mm 28 mm 28 mm 22.5 mm 26.5 mm 26.5 mm 3510 Vauxhall/Opel Omega 9 9•2 Braking system Front brakes (continued) Disc thickness (minimum, wear limit): Up to 1998 model year: 4 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . From 1998 model year: All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disc maximum thickness variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disc maximum run-out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disc maximum score depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Brake pad thickness (including backplate): New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Minimum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Caliper piston diameter: Up to 1998 model year: 4 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 cylinder engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . From 1998 model year: All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . *After machining the disc surface, new brake pads must be fitted. Once new discs must then be fitted. 21 mm 25 mm 25 mm 0.01 mm 0.12 mm 0.4 mm 17.5 ± 0.6 mm 8.0 mm 54 mm 54 mm 57 mm these are worn, no more new pads may be used with the same discs - Rear brakes Discs diameter (new) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 mm Disc thickness: New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.0 mm Minimum (after machining*) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.0 mm Minimum (wear limit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.0 mm Variation (maximum) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.01 mm Run-out (maximum) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.12 mm Caliper piston diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40.0 mm Brake pad thickness (including backplate): New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17.0 mm Minimum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.0 mm Handbrake shoe minimum thickness (lining only) . . . . . . . . . . . . . . . . . 1.0 mm Handbrake drum diameter: New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160.0 mm Maximum (wear limit**) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161.0 mm *After machining the disc surface, new brake pads must be fitted. Once these are worn, no more new pads may be used with the same discs new discs must then be fitted. **After machining the drum surface, new brake shoes must be fitted. Once these are worn, no more new shoes may be used with the same drums - new drums must then be fitted. Torque wrench settings Nm lbf ft ABS control unit bracket to modulator . . . . . . . . . . . . . . . . . . . . . . . . . . 8 6 ABS modulator to bodywork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7 ABS modulator-to-bracket nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 6 ABS wheel sensor securing screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 6 Brake disc locking screw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3 Brake line union nuts/bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 12 Brake pedal bracket to bulkhead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15 Brake pedal shaft to bracket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 13 Caliper bleed screw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 7 Caliper brake hose union bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 30 Caliper guide bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 22 Front caliper mounting bracket-to-steering knuckle bolts (all calipers)*: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 70 Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Angle-tighten through 30º to 45º Handbrake lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15 Master cylinder front mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 16 Master cylinder to vacuum servo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 16 Rear caliper mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 59 Road wheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 81 Vacuum servo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 15 *Use new bolts. Note: The threads of all fasteners secured with locking compound must be thoroughly cleaned and, if necessary, re-cut to remove all traces of the old locking compound. Fresh locking compound should then be reapplied at reassembly. 3510 Vauxhall/Opel Omega Braking system 9•3 1 General description 1 The braking system is of dual hydraulic circuit type with front and rear discs. The front and rear hydraulic circuits are operated independently, so that in the event of a failure in one circuit the remaining circuit still functions. The floor-mounted handbrake lever operates brake shoes by means of a cable. The handbrake shoes are mounted inside the rear brake discs; the inner surface of each rear brake disc incorporates a brake drum. The disc brakes are self-adjusting in use, however the handbrake is adjusted manually. 2 An Anti-lock Braking System (ABS) is fitted as standard equipment on all models. Pre1998 models have 3-channnel ABS, with independent hydraulic circuits for each front brake, and a shared hydraulic circuit for the rear brakes. Later models have 4-channel ABS, with independent circuits for all four brakes. 3 During braking, the ABS system adjusts the braking system hydraulic pressure, to prevent the road wheels from locking, thereby reducing the likelihood of skidding in slippery conditions and/or during heavy braking. The system incorporates an electronic control unit which is supplied with signals from the wheel speed sensors. The signals are compared with each other and, if one wheel is found to be decelerating more rapidly than the others, the hydraulic pressure to that wheel is reduced until its speed matches the other wheels. The ABS unit is fitted in the hydraulic lines leading from the master cylinder to the brakes, the vacuum servo unit and master cylinder being of similar type for both non-ABS and ABS models. The ABS control system also manages the operation of the Traction Control (TC) system fitted to models with 6-cylinder engines. For more details of the ABS/TC systems, refer to Sections 17 and 18. 4 Should the ABS develop a fault, it is recommended that a complete system check is carried out by a GM dealer or ABS specialist, who will have access to the specialist equipment necessary to make an accurate diagnosis of the problem. 2.5 Unclip the pad wear sensor from the caliper aperture 2 Front brake pads inspection, removal and refitting 3 Warning: Renew both sets of front brake pads at the same time never renew the pads on only one wheel, as uneven braking may result. Note that the dust created by wear of the pads may contain asbestos, which is a health hazard. Never blow it out with compressed air, and don’t inhale any of it. An approved filtering mask should be worn when working on the brakes. DO NOT use petroleum-based solvents to clean brake parts - use brake cleaner or methylated spirit only. Removal 1 Apply the handbrake. Jack up the front of the vehicle and support it on axle stands. Remove the front wheels. 2 Turn the steering to full right-hand lock and check the wear of the linings on the right-hand brake pads through the inspection aperture at the front of the caliper body. Check that the thickness of the lining including the backing plate is as shown in the Specifications using a steel rule or vernier calipers. 3 Turn the steering to full left-hand lock and check the left-hand brake pads in the same way. 2.6 Slide out the metal retaining clip and release the brake hose from the suspension strut 4 If any brake pad is worn below the minimum thickness, renew all the front pads as a set together with new anti-rattle springs, as described in the following paragraphs. 5 Using a small flat bladed screwdriver, unclip the pad wear sensor from the caliper aperture, and position it clear of the work area (see illustration). 6 Slide out the metal retaining clip and release the brake hose from its support bracket at the side of the suspension strut (see illustration). 4-cylinder engined models up to 1998 7 Remove the large spring clip from the side of the brake caliper (see illustration). The clip is under relatively high tension and may fly off with some force when released; to prevent injury, cover the spring with a large rag before prising it from the caliper with a stout screwdriver. 8 Remove the dust caps from the caliper guide pin bolt holes, then slacken and remove the two guide pin bolts (see illustrations), and withdraw them from the caliper. 9 Withdraw the caliper from its mounting bracket, then tie the caliper to the suspension strut, using a suitable piece of wire (see illustration). Warning: Take great care to avoid kinking or placing any strain on the flexible brake hose. 10 Remove the outer pad from the caliper mounting bracket. 9 2.7 Remove the large spring clip from the side of the brake caliper 2.8a Remove the dust caps . . . 3510 Vauxhall/Opel Omega 2.8b . . . then slacken and remove the two guide pin bolts 9•4 Braking system 15 First measure the thickness of each brake pad (friction material and backing plate) (see illustration). If either pad is worn at any point to the specified minimum thickness (see Specifications), all four front brake pads must be renewed, so that even braking balance is maintained. The pads should also be renewed if any are fouled with oil or grease; there is no satisfactory way of degreasing friction material, once it is contaminated. If any of the brake pads are worn unevenly or fouled with oil or grease, trace and rectify the cause before reassembly. If the pad wear sensor has been in contact with the brake disc (causing the brake pad warning light to illuminate), that must also be renewed. 16 Inspect the brake disc with reference to the information given in Section 6. 17 If the brake pads are still serviceable, carefully clean them using a clean, fine wire brush or similar, paying particular attention to the sides and back of the metal backing. Clean out the grooves in the friction material (where applicable), and pick out any large embedded particles of dirt or debris. Carefully clean the pad locations in the caliper body and mounting bracket. Check that the guide pins are free to slide easily in the caliper mounting bushes. Brush the dust and dirt from the caliper and piston, but do not inhale it, as it is injurious to health. Inspect the dust seal around the piston for damage, and the piston for evidence of fluid leaks, corrosion or damage. If attention to any of these components is necessary, refer to the information given in the following sub-section. 18 If new brake pads are being fitted, the caliper piston must be pushed back into the cylinder to make room for the greater depth of friction material. Either use a G-clamp or similar tool, or use suitable pieces of wood as levers (see illustration). Provided that the master cylinder reservoir has not been overfilled with hydraulic fluid, there should be no spillage, but keep a careful watch on the fluid level while retracting the piston. If the fluid level rises above the maximum level mark, the surplus should be siphoned off using a syringe, or ejected via a plastic tube connected to the bleed screw, to avoid overflow, before retracting the piston any further. 19 Prior to fitting the pads, check that the guide bolts are a snug fit in the caliper bushes. Remove any remaining dust and dirt 2.12a Slacken the lower guide pin bolt, counterholding the guide pin with a second spanner . . . 2.12b . . . and withdraw the guide pin bolt from the caliper 2.13 Pivot the caliper upwards to expose the brake pads 2.14a Remove the outer . . . 2.14b . . . and inner brake pads from the caliper bracket 2.15 Measuring the thickness of a brake pad 2.9 Remove the caliper from its mounting brackets 11 Carefully prise the inner pad from the caliper piston, which is retained by metal spring clip attached to the rear of the pad backing plate (see illustration). 4-cylinder engined models from 1998 and all 6-cylinder engined models 12 Remove the dust caps from the caliper lower guide pin bolt hole, then slacken the lower guide pin bolt, and withdraw it from the caliper. Counterhold the guide pin with a second spanner (see illustrations). 13 Pivot the caliper upwards (see illustration), to expose the brake disc and pads. Suspend the caliper in the vertical position, using a suitable piece of wire. Warning: Take great care to avoid kinking or placing any strain on the flexible brake hose. 14 Remove both brake pads from the caliper bracket (see illustrations). 2.11 Carefully prise the inner pad from the caliper piston Inspection 3510 Vauxhall/Opel Omega Braking system 9•5 2.18 Using a retraction tool to push the piston back into the brake caliper 2.19a Apply a little high-melting-point copper brake grease to the brake pad backing plates . . . 2.19b . . . and the brake pad contact points on the caliper mounting bracket from the caliper, piston and caliper mounting bracket using a stiff brush and proprietary brake component cleaning fluid - the use of other solvents or cleaning agents may cause damage to the caliper rubber seals. Apply a little high-melting-point copper brake grease to the areas on the pad backing plates and caliper mounting bracket which contact the caliper and piston (see illustrations). Caution: Take great care to avoid contaminating the pad friction material and brake disc surface. Inspect the dust seal around the piston for damage, and the piston for evidence of fluid leaks, corrosion or damage. If attention to any of these components is necessary, refer to front brake caliper overhaul information in Section 4. brake disc. Check that the pads slide easily along their guides towards the brake disc. 26 Pivot the caliper body down over the pads, ensuring that caliper piston bears against the rear of the inner pad’s backing plate and that the outer edge of the caliper bears against the rear of the outer pad’s backing plate. Check that the butterfly springs at the edge of the pad bear on the inside of the caliper and are not jammed in the caliper inspection aperture. 27 Thoroughly clean the threads of the caliper lower guide pin bolt, fit it to the caliper and then tighten it to the specified torque. Refit the dust cover. 31 Refit the roadwheels, then lower the car to the ground and tighten the roadwheel bolts to the specified torque setting. 32 Check the hydraulic fluid level and top up if necessary. Refitting 4-cylinder engined models up to 1998 20 Fit the inner brake pad to the caliper by pressing the spring clip on the pad backing plate into the piston. Check that the butterfly spring at the edge of the pad bears on the inside of the caliper and is not jammed in the caliper inspection aperture. 21 Place the outer pad in the caliper mounting bracket, with the friction material facing the disc, and check that it slides freely along its guides towards the brake disc. 22 Fit the brake caliper and outer pad over the disc, ensuring that the outer edge of the caliper bears squarely on the rear of the outer brake pad’s backing plate. Check that the butterfly spring at the edge of the pad bears on the inside of the caliper and is not jammed in the caliper inspection aperture. 23 Thoroughly clean the threads of the caliper guide pin bolts, fit them to the caliper and then tighten them to the specified torque. Refit the dust covers. 24 Refit the caliper spring, ensuring that its ends are firmly pressed into the holes in the side of the caliper body (see illustration). 3 Rear brake pads inspection and renewal 3 Note: Before starting work, refer to the note at the beginning of Section 2 concerning the dangers of hydraulic fluid, and asbestos dust. Inspection All models 28 Clip the pad wear sensor into position on the inner brake pad. If a new sensor is being installed, trace the wiring of the original sensor back to the connector, then disconnect it and remove the old sensor from the vehicle. Connect the wiring connector of the new sensor, ensuring that the wiring is correctly routed and retained by all the necessary clips. 29 Check that the caliper body slides smoothly on its guide pins, then depress the brake pedal repeatedly until the pads are pressed into firm contact with the brake disc, and normal (non-assisted) pedal pressure is restored. 30 Repeat the above procedure on the remaining front brake caliper. 1 Chock the front wheels then jack up the rear of the vehicle and support it on axle stands. Release the handbrake. Remove the rear wheels. 2 Inspect the brake pad linings for wear. Using a steel rule or vernier calipers, check that the thickness of the lining including the backing plate is as shown in the Specifications. 3 If any brake pad is worn below the minimum thickness, renew all the rear pads as a set together with new anti-rattle springs. Removal 4 Note how the anti-rattle spring is located, then drive out the upper pad securing pin using a thin punch from the outside (see illustration). 9 4-cylinder engined models from 1998 and all 6-cylinder engined models 25 Fit the inner and outer brake pads to the caliper mounting bracket ensuring that the friction material is facing the surface of the 2.24 Refit the caliper spring, ensuring that its ends are firmly pressed into the holes in the side of the caliper body 3510 Vauxhall/Opel Omega 3.4 Driving out the upper rear brake pad pins using a thin punch 9•6 Braking system 3.5a Remove the anti-rattle spring . . . 3.5b . . . then drive out the lower pad securing pin 3.6a Use a pair of grips . . . 3.6b . . . or a pad extraction tool . . . 3.6c . . . to remove the brake pads from the caliper 3.8 Using a retraction tool to press the pistons back into the caliper body 5 Remove the anti-rattle spring, then drive out the lower pad securing pin (see illustrations). 6 Push the brake pads apart slightly to give a small amount of clearance then pull them from the caliper (see illustrations). If they are tight, use pliers or a pad extraction tool to remove them. 15 Refit the rear wheels and lower the vehicle to the ground. Check the brake fluid level with reference to Weekly checks. 7 Brush the dust and dirt from the caliper and intermediate plates, but take care not inhale it. Clean any rust from the edge of the brake disc. 8 Press both pistons fully into their cylinders using a length of wood or piston retraction tool (see illustration). 9 Check that the cut-away recesses on the pistons are positioned downwards at approximately 23º to the horizontal. A template made of card may be used to check the setting (see illustration). If necessary, turn the pistons to their correct positions. 10 Apply a little high-melting point grease to the top and bottom edges of the backplates on the new brake pads (see illustration). Take great care to avoid contaminating the brake pad friction material with grease. 11 Insert the new brake pads in the caliper and check that they are free to move. 12 Locate the anti-rattle spring on the pads, then insert the pins from the inside while depressing the spring. Tap the pins firmly into the caliper (see illustration). 13 Renew the brake pads on the remaining rear wheel in the same manner. 14 Depress the footbrake pedal several times in order to reset the brake pads to their normal position. 3.9 Check that the cut-away recesses on the pistons are positioned downwards at approximately 23º to the horizontal 3.10 Apply a little high-melting point grease to the top and bottom edges of the backplates on the brake pads 3.12 Drive the brake pad securing pins in from the inner surface of the caliper Refitting 3510 Vauxhall/Opel Omega 4 Front brake caliper removal, overhaul and refitting 4 Removal Note: Before starting work, refer to the note at the beginning of Section 2 concerning the dangers of hydraulic fluid, and asbestos dust. 1 Apply the handbrake then jack up the front of the vehicle and support it on axle stands. Remove the relevant road wheel. 2 On pre-1998 models with 4-cylinder engines, locate the large spring clip at the Braking system 9•7 4.3a Slacken the upper guide pin bolt, counterholding the guide pin with a second spanner . . . 4.3b . . . withdraw the guide pin bolt from the caliper . . . 4.3c . . . and remove the caliper from its mounting bracket side of the brake caliper. The clip is under relatively high tension and may fly off with some force when released; to prevent injury, cover the spring with a large rag before prising it from the caliper with a stout screwdriver. 3 Remove the dust caps from the caliper guide pin bolt holes, then slacken both guide pin bolts, and withdraw them from the caliper (see illustrations). 4 Withdraw the caliper from its mounting bracket, then tie the caliper to the suspension strut, using a suitable piece of wire. Warning: Take great care to avoid kinking or placing any strain on the flexible brake hose. 5 On post-1998 models with 4-cylinder engines and all models with 6-cylinder engines, remove both brake pads from the caliper mounting bracket. 6 On pre-1998 models with 4-cyliner engines, remove the outer pad from the caliper mounting bracket, then carefully prise the inner pad from the caliper piston, which is retained by metal spring attached to the rear of the pad backing plate. 7 Fit a brake hose clamp to the flexible hose leading to the brake caliper. Alternatively remove the cap from the hydraulic fluid reservoir and refit it with a piece of polythene sheeting covering the opening to help minimise the loss of brake fluid when the caliper hose is disconnected. 8 Clean the area around the union, then undo the brake hose union bolt, and disconnect the hose from the caliper - be prepared for some brake fluid leakage. Plug the end of the hose and the caliper orifice, to prevent dirt entering the hydraulic system. Discard the sealing washers; they must be renewed whenever disturbed. 9 Slacken and remove the two securing bolts, then detach the caliper mounting bracket from the hub carrier (see illustrations). Warning: Use eye protection during this procedure, as droplets of brake fluid may be ejected as the piston leaves the cylinder under pressure. Keep your hands away from the end of the piston as it will leave the cylinder with considerable force. 13 Using a blunt, non-metallic instrument (such as an old plastic knife), extract the piston hydraulic seal, taking great care not to damage the caliper bore. 14 Press the rubber guide sleeves out of the caliper body using a suitable socket (see illustration). 15 Thoroughly clean all components, using only clean brake fluid as a cleaning medium. Never use mineral-based solvents such as petrol or paraffin, as they will attack the hydraulic system’s rubber components. Dry the components immediately, using compressed air or a clean, lint-free cloth. Use compressed air to blow clear the fluid passages. Overhaul 10 With the caliper on the bench, wipe away all traces of dust and dirt using copious quantities of brake cleaning fluid. Warning: Avoid inhaling the brake dust, as it may contain asbestos which is injurious to health. 11 On post-1998 models with 4-cylinder engines and all models with 6-cylinder engines, prise open the three tangs and remove the protective plate from the contact face of the piston. 12 Withdraw the piston from the caliper body, and remove the dust seal. The piston can be withdrawn by hand, or can if necessary be pushed out by applying compressed air to the brake pipe union bolt hole. Only low pressure should be required, such as that generated by a foot pump - place a block of hardwood between the end of the piston and the caliper body to prevent damage to the piston as it exits from the cylinder. Warning: Wear eye protection when using compressed air! 16 Check all components, and renew any that are worn or damaged. Pay particular attention to the cylinder bore and piston; these must be renewed if they are scratched, worn or corroded in any way (see illustration). 9 4.9a Slacken and remove the two securing bolts . . . 4.9b . . . then detach the caliper mounting bracket from the hub carrier 3510 Vauxhall/Opel Omega 4.14 Prise open the three tangs and remove the protective plate from the contact face of the piston 9•8 Braking system 4.16 Extract the piston hydraulic seal using a blunt, non-metallic instrument Warning: Do not use abrasives or tools to remove any material from the piston or cylinder in an attempt to effect a repair or remove corrosion - the piston and caliper body must be renewed as a complete assembly. 17 Where applicable, check the condition of the guide bolts/pins and their sleeves; both guide bolts/pins should be undamaged and (when cleaned) a reasonably-tight sliding fit in the sleeves. If there is any doubt about the condition of any component, renew it. 18 If the assembly is fit for further use, obtain new piston and dust seals, and a tube of brake cylinder paste from a Vauxhall dealer. 19 Smear a little brake cylinder paste onto the surfaces of the caliper bore, piston and piston seal. 20 Install the piston seal in the caliper bore, using only your fingers to manipulate it into its groove - do not use tools that may damage the new seal. 21 Fit the new dust seal to the caliper cylinder, ensuring that the inner edge seats correctly in the cylinder groove. 22 Offer up the piston to the cylinder and ease the lip at the outer edge of the dust seal over the end of the piston. 23 Carefully press the piston to the caliper bore, using a twisting motion, ensuring that it enters the bore squarely. 24 Press the piston fully into the bore, until the outer edge of the dust seal drops into the groove at the outer edge of the piston. On pre-1998 models with 4-cyliner engines, rotate the piston so that the raised section of the piston contact surface is positioned horizontally in relation to the caliper body (see illustration). 25 On post-1998 models with 4-cylinder engines and all models with 6-cylinder engines, fit the protective plate in position on the piston contact surface and press the three tangs into their corresponding recesses. 26 Lubricate the rubber caliper guide sleeves with a little soapy water, then press them into position in the caliper body. 27 Finally, clean the caliper mounting bracket to remove all traces of dust and corrosion, using a wire brush if necessary. Pay particular attention to the machined surfaces which come into contact with the brake pads. Refitting 28 Refit the caliper mounting bracket to the hub carrier, then fit new securing bolts and tighten them to the specified torque. 29 Apply a little high-melting-point brake grease to the areas on the pad backing plates and caliper mounting bracket which contact the caliper and piston. Caution: Take great care to avoid contaminating the pad friction material and brake disc surface. 4-cylinder engined models up to 1998 30 Fit the inner brake pad to the caliper by pressing the spring clip on the pad backing plate into the piston. Check that the butterfly spring at the edge of the pad bears on the inside of the caliper and is not jammed in the caliper inspection aperture. 31 Place the outer pad in the caliper mounting bracket, with the friction material facing the disc, and check that it slides freely along its guides towards the brake disc. 32 Fit the brake caliper and outer pad over the disc, ensuring that the outer edge of the caliper bears squarely on the rear of the outer brake pad’s backing plate. Check that the butterfly spring at the edge of the pad bears on the inside of the caliper and is not jammed in the caliper inspection aperture. 33 Thoroughly clean the threads of the caliper guide pin bolts, fit them to the caliper and then tighten them to the specified torque. Refit the dust covers. 34 Refit the caliper spring, ensuring that its ends are firmly pressed into the holes in the side of the caliper body. plate and that the outer edge of the caliper bears against the rear of the outer pad’s backing plate. Check that the butterfly springs at the edge of the pad bear on the inside of the caliper and are not jammed in the caliper inspection aperture. 37 Thoroughly clean the threads of the caliper guide pin bolts, fit them to the caliper and then tighten them to the specified torque. Refit the dust covers. All models 38 Position a new sealing washer on each side of the brake hose union, then pass the bolt through the union and thread it into the caliper. Ensure that the brake hose union is correctly positioned against the lug on the caliper, and tighten the union bolt to the specified torque setting. Remove the brake hose clamp (where applicable). 39 Clip the pad wear sensor into position on the inner brake pad. If a new sensor is being installed, trace the wiring of the original sensor back to the connector, then disconnect it and remove the old sensor from the vehicle. Connect the wiring plug of the new sensor, ensuring that the wiring is correctly routed and retained by all the necessary clips. 40 Bleed the hydraulic system as described in Section 12. Note that, providing the precautions described were taken to minimise brake fluid loss, it should only be necessary to bleed the relevant caliper. 41 Refit the roadwheel, then lower the car to the ground and tighten the roadwheel bolts to the specified torque. 42 Thoroughly check the operation of the braking system before bringing the vehicle back into service on the public highway. 5 Rear brake caliper removal, overhaul and refitting 4 Removal 1 Chock the front wheels then jack up the rear of the vehicle and support it on axle stands. Remove the wheel. 2 Fit a brake hose clamp to the flexible hose leading to the brake caliper (see illustration). 4-cylinder engined models from 1998 and all 6-cylinder engined models 4.24 Rotate the piston so that the raised section of the piston contact surface is positioned horizontally in relation to the caliper body 35 Fit the inner and outer brake pads to the caliper mounting bracket ensuring that the friction material is facing the surface of the brake disc. Check that the pads slide easily along their guides towards the brake disc. 36 Place the caliper body in position over the brake pads, ensuring that caliper piston bears against the rear of the inner pad’s backing 3510 Vauxhall/Opel Omega 5.2 Fit a brake hose clamp to the flexible hose leading to the brake caliper Braking system 9•9 5.4a Unscrew the union nut . . . 5.4b . . . and disconnect the rigid brake line from the caliper Alternatively remove the cap from the hydraulic fluid reservoir and refit it with a piece of polythene sheeting covering the opening to help prevent loss of brake fluid when the caliper hose is disconnected. 3 Remove the brake pads as described in Section 3. 4 Unscrew the union nut securing the rigid brake line to the caliper, and remove the brake line (see illustrations). 5 Unscrew the hexagon mounting bolts and withdraw the caliper from the semi-trailing arm (see illustration). rotate them so that the cut-away recesses are positioned downwards at an angle of approximately 23º; this ensures that only the raised section of the piston contact face bears on the rear of the pad. Overhaul 6 Clean the outer surfaces of the caliper. 7 Note that no attempt must be made to separate the two halves of the caliper. 8 Prise the rings and dust covers from each side of the caliper and pull the covers from the piston grooves (see illustration). 9 Position a thin piece of wood between the pistons, then using air pressure from an air line or foot pump through the fluid inlet, carefully force the pistons from the cylinders. If one piston exits before the other, remove the piston and then seal off the open cylinder to allow the remaining piston to be ejected. 10 Prise the piston seals from the cylinders, taking care not to scratch the bore surfaces. 11 Clean the pistons and cylinders with new brake fluid and allow to dry. Examine the surfaces of the pistons and cylinder bores for wear, damage and corrosion. If evident, renew the caliper complete, however if the surfaces are good obtain a repair kit which includes piston seals and dust covers. Also obtain a tube of brake cylinder paste. 12 Apply a little brake cylinder paste to the pistons, cylinder bores and piston seals. 13 Locate the piston seals in the cylinder grooves, then insert the pistons carefully until they enter the seals. It may be necessary to rotate the pistons to prevent them jamming in the seals. Do not press the pistons fully into the cylinders at this stage as it will be difficult to fit the dust covers. 14 Ease the dust covers into the piston grooves then locate them on the caliper housing. Press the retaining rings over the dust covers. 15 Press the pistons into their cylinders, then 5.5a Unscrew the hexagon mounting bolts . . . Make up a card template to check the setting. Refitting 16 To refit the caliper locate it on the semi-trailing arm, insert the mounting bolts and tighten them to the specified torque (see illustration). 17 Locate the rigid brake line on the caliper and tighten the union nut to the specified torque. 18 Refit the brake pads with reference to Section 3. 19 Remove the brake hose clamp or polythene sheeting and bleed the hydraulic system as described in Section 12. Provided that there has been no loss of brake fluid, it should only be necessary to bleed the caliper which was removed, however if brake fluid has been lost, then bleed the complete system. 20 Refit the wheel and lower the vehicle to the ground. Check the operation of the braking system before using the vehicle. 5.5b . . . and withdraw the caliper from the semi-trailing arm 6 Brake disc inspection, removal and refitting 3 Inspection 1 Jack up the front or rear of the vehicle as applicable and support it on axle stands. Release the handbrake and chock the front wheels if checking a rear disc. Remove the appropriate wheel. 2 Check that the brake disc securing screw is tight, then refit and tighten a wheel bolt opposite the screw using a spacer washer approximately 10.0 mm (0.4 in) thick. 3 Rotate the brake disc and examine it for deep scoring or grooving. Light scoring is normal, but if excessive, the disc should be removed and either renewed or machined within limits by a suitable engineering works. 9 5.8 Removing the dust cover ring from the rear brake caliper 3510 Vauxhall/Opel Omega 5.16 Tighten the caliper mounting bolts to the specified torque 9•10 Braking system 6.4 Checking the front brake disc runout 6.6 Checking the thickness of the front brake disc using a micrometer 6.8a Remove the securing screw . . . 6.8b . . . then withdraw the front brake disc from the hub 6.9a Remove the securing screw . . . 6.9b . . . and withdraw the rear brake disc from the hub It is worth mentioning that some garages may be able to regrind the discs in situ, using a specially adapted electric grinder. 4 Using a dial gauge, or metal block and feeler gauges, check that the disc run-out does not exceed the amount given in Specifications, measured at a radius of approximately 10.0 mm from the outer edge of the disc (see illustration). Check the run-out at several positions around the disc. 5 If the run-out is excessive, remove the disc and check that the disc-to-hub surfaces are perfectly clean. Refit the disc and check the run-out again. 6 Check the thickness of the disc using a micrometer at several points across the area swept by the brake pads (see illustration). Compare your measurement with the figures listed in the Specifications. If either of the discs has worn beyond its minimum permissible thickness at any point, both discs must be renewed as pair. caliper mounting bracket from the hub carrier, as described in Section 4. 9 To remove a rear disc, unbolt the brake caliper from the semi-trailing arm as described in Section 5, and support it away from the disc, taking care not to damage the rigid brake line. Slacken the handbrake adjustment screw via the access hole in brake disc, as described in Chapter 1, Section 9 this will retract the handbrake shoes from the inside of the disc. Remove the securing screw and withdraw the brake disc from the hub (see illustrations). Section 2 or 3 (as applicable). After refitting a rear brake disc, adjust the handbrake as described in Chapter 1, Section 9. Refitting 10 Refitting is a reversal of removal, but make sure that the mating faces of the disc and hub are perfectly clean, and before inserting the securing screw apply a little locking fluid to its threads. Refit the brake pads with reference to Removal 7 To remove the brake disc, first remove the brake pads as described in Section 2 (front brake pads) or Section 3 (rear brake pads). On models with 6-cylinder engines and post1998 models with 4-cylinder engines, unbolt the caliper body from its mounting bracket, as described in Section 4. 8 To remove a front disc, remove the securing screw then withdraw the disc from the hub, tilting it as necessary to clear the brake caliper (see illustrations). On later models it may be necessary to unbolt the 7 Handbrake shoes inspection, removal and refitting 4 Note: Before starting work, refer to the note at the beginning of Section 2 concerning the dangers of hydraulic fluid, and asbestos dust. Inspection 1 Remove the rear brake discs as described in Section 6. 2 Brush the dust and dirt from the shoes, backplate and from inside the disc drum. 3 Check the thickness of the linings on the shoes and if less than shown in the Specifications, renew the shoes at both rear brakes as a complete axle set. 4 Also check the surface inside the drums. These should not normally be worn unless the handbrake has been binding; check the diameter of the inner surface and compare it with the figure listed in Specifications. Removal 7.6 Handbrake shoe anti-rattle spring (arrowed) - early model 3510 Vauxhall/Opel Omega 5 Unhook the return spring from the lever on the rear of the brake backplate then unhook the handbrake cable from it. 6 Using a screwdriver through a hole in the hub flange, twist and remove the brake shoe anti-rattle springs and retaining pins (see illustration). Braking system 9•11 7.7 On later models, where the retaining pins are not cross-headed, depress the spring cups and turn them through 90° using two pairs of pliers 7.9a Handbrake shoe adjuster (A) and spring (B) 7.9b Handbrake shoe lower lever assembly 7 On later models, where the retaining pins are not cross-headed, depress the spring cups and turn them through 90° using two pairs of pliers (see illustration). This is a difficult task due to the strong spring tension and limited access - an alternative method is to use a small socket, inserted on a the end of an extension bar through the holes in the hub flange, to depress the springs. To remove the pins from the backplate, first remove the backplate heatshield securing screws via the holes in the hub flange, then move the heatshield to one side to allow the withdrawal of the shoe retaining pins. 8 Mark the brake shoes for location. Also note the fitted positions of the return springs. 9 Prise the brake shoes from the adjuster and lever. Disconnect the upper and lower return springs from the brake shoes (see illustrations), then remove the brake shoes from the backplate. 10 Remove the adjuster and handbrake cable shoe actuator lever. 11 Clean the backplate, springs, adjuster and lever. 12 Apply a little brake grease to the threads of the adjuster then screw it together to its minimum length. temporarily holding the backplate in position on the trailing arm using two bolts. After reassembly the rear hub can then be refitted. 14 Reassemble the lever assembly and apply a little copper grease to the contact surfaces, then refit to the backplate and insert through the rubber grommet (see illustrations). 15 Refit the handbrake cable to the shoe actuator lever, then refit the return spring (see illustration). 16 Apply a thin smear of high-temperature copper-based brake grease or anti-seize compound to the shoe contact surfaces on the backplate. 17 With the pins already fitted to the backplate, refit the front (trailing) shoe and secure with the hold-down spring and cup (see illustrations). 7.14a The lever assembly dismantled 7.14b The lever assembled Refitting 13 Prior to installation, clean the backplate thoroughly. The handbrake shoes can be reassembled using a reversal of the dismantling procedure, however improved access is possible by removing the rear hub assembly as described in Chapter 10 and 7.14c Refitting the lever assembly to the backplate 9 7.15 Refitting the return spring 7.17a Locate the front (trailing) shoe on the backplate . . . 3510 Vauxhall/Opel Omega 7.17b . . . then refit the spring and cup . . . 9•12 Braking system 7.17c . . . and use a pair of pliers to depress and turn the cup 7.18a Refit the rear (leading) shoe and the lower return spring 7.18b Engage the bottom of the shoe on the lever . . . 7.19 . . . then refit the hold-down spring and cup 7.20 Refit the adjuster between the upper ends of the shoes 7.21 Hook the upper return spring on the shoes 18 Locate the rear (leading) shoe on the lever assembly and refit the lower return spring (see illustrations). 19 Refit the hold-down spring and cup to secure the leading shoe to the backplate (see illustration). 20 Refit the adjuster between the upper ends of the shoes (see illustration). 21 Hook the upper return spring on the shoes (see illustration). 22 Where removed the rear hub can now be refitted (see illustration). 23 Temporarily refit the disc over the shoes to determine the adjustment, then if necessary use a screwdriver to turn the serrated adjuster nut until it is just possible to refit the disc over the shoes without them binding (see illustration). 24 Refit the brake disc with reference to Section 6. 25 Adjust the handbrake as described in Chapter 1. 26 Refit the roadwheels and lower the vehicle to the ground. 1 Chock the front wheel, then jack up the rear of the vehicle and support it on axle stands. Remove the rear wheels and release the handbrake. 2 On models with 4-cylinder engines, unhook the rear and intermediate silencer rubber mountings from their floorpan mountings. Suspend the rear section of the exhaust system on axle stands, or using lengths of wire, so that access to the heat shields can be gained. See Chapter 4A for details. 3 On models with 6-cylinder engines, unbolt the rear section of the exhaust system at the joints downstream of both catalytic converters. Remove the tailpipe and intermediate silencers from underneath the vehicle as a complete assembly. See Chapter 4A for details. 4 Unscrew the securing bolts and lower the exhaust system heatshields away from the underside of the vehicle (see illustration). 5 Unscrew and remove the propeller shaft centre bearing retaining bolts, with reference to Chapter 8, Section 11. Support the centre bearing on an axle stand. 6 Locate the compensator bar at the front end of the handbrake cable (see illustration). Unscrew the adjustment nut from the threaded handbrake lever rod, counting the 7.22 The handbrake shoes assembled ready for refitting of the rear hub 7.23 Using a screwdriver through the hole in the drive flange to turn the serrated nut on the adjuster 8.4 Unscrew the securing bolts and lower the exhaust system heatshields away from the underside of the vehicle 8 Handbrake cable removal and refitting 3 Removal 3510 Vauxhall/Opel Omega Braking system 9•13 number of turns required to remove it; record the number for use later. 7 Slide the compensator bar from the threaded handbrake lever rod. 8 Working at each rear brake caliper in turn, unhook the return spring from the lever on the rear of the brake backplate, then unhook the handbrake cable. 9 Pull the rear of the outer cable from the guide on the semi-trailing arm on both sides. 10 Pull the front ends of the outer cables from the guides, and unhook the inner cables. Release the remainder of each cable from its respective retaining clips, then withdraw the cable assembly from under the vehicle. Refitting 11 Refitting is a reversal of removal, noting the following points:. a) Use a new compensator bar adjustment nut and screw it onto the threaded handbrake lever rod by the number of turns noted during removal. b) Apply some molybdenum disulphide paste to the plastic guides at the front of the inner cables. c) Refit the exhaust system with reference to Chapter 4A. d) Refit the propeller shaft centre bearing with reference to Chapter 8. e) Finally, adjust the handbrake as described in Chapter 1. 9 Handbrake lever removal and refitting 3 Removal 1 Chock the front wheels then jack up the rear of the vehicle and support it on axle stands. 2 Remove the screws and lower the metal heat shield away from the propeller shaft centre bearing. Unbolt and withdraw the propeller shaft centre bearing bolts as described in Chapter 8. Support the centre bearing on an axle stand. 3 At the front of the handbrake cable unscrew the adjustment nut from the threaded handbrake lever rod, and slide off the compensator bar; see Section 8 for details. 4 Prise the rubber gaiter from the underbody and remove it from the handbrake lever rod. 5 Remove the rear section of the centre console; see Chapter 11 Section 30 for details. 6 Unclip and remove the handbrake lever folding cover. Remove the securing nuts and detach the air ducting from its support bracket. Move the ducting to the left, away from the work area. 7 Unscrew the handbrake lever mountings bolts, then disconnect the wiring from the warning switch. 8 Remove the handbrake lever from the vehicle. Refitting 8.6 Handbrake cable compensator bar adjuster nut (arrowed) Refitting 9 Refitting is a reversal of removal, but on completion adjust the handbrake cable as described in Chapter 1. 10 Master cylinder removal and refitting 4 Removal 1 Depress the footbrake pedal several times to dissipate the vacuum in the servo unit. 2 Remove the fluid reservoir from the master cylinder, as described in Section 11. 3 Locate a container beneath the master cylinder to catch spilled brake fluid. 4 Identify the brake lines for position, then unscrew the union nuts and pull the lines from the master cylinder. Plug the open ports and brake pipes to minimise fluid leakage and prevent the ingress of foreign material. 5 Unscrew the mounting nuts and withdraw the master cylinder from the studs on the vacuum servo unit (see illustration). Take care not to drop any brake fluid on the body paintwork. If accidentally spilt, wash off immediately with copious amounts of cold water. 6 Extract the O-ring seal from the master cylinder sealing surface, and the rubber grommets from the fluid reservoir ports, then discard them as new items must be fitted. 7 Fit a new O-ring seal to the master cylinder mating surface, and new rubber grommets to the fluid reservoir ports. 8 Refit the master cylinder to the brake servo, then fit and tighten the mounting nuts to the specified torque. 9 Reconnect the brake pipes to the master cylinder ports and tighten the unions to the specified torque. A crow’s-foot adapter may be required to apply torque to the union nuts. 10 Refit the brake fluid reservoir as described in Section 11. 11 On completion, bleed the entire brake hydraulic system as described in Section 12. 12 Check the master cylinder unions for signs of leakage and test the operation of the braking system thoroughly before using the vehicle on the road. 11 Brake fluid reservoir and level sensor removal and refitting 2 Reservoir Removal 1 Ensure that ignition key is turn to the Off position, then unplug the wiring from the fluid reservoir level sensor at the connector. 2 Unscrew the cap from the fluid reservoir, then remove as much of the brake fluid as is possible; use an old poultry baster or similar tool - do not siphon the fluid out as it is poisonous. Discard the fluid as it will not be fit for re-use. 3 Slacken and separate the union, then disconnect the clutch master cylinder supply pipe from the side of the fluid reservoir. 4 Carefully prise the fluid reservoir from the brake master cylinder ports. Extract the rubber grommets from the brake master cylinder and discard them. Clean the ports at the base of the fluid reservoir. Refitting 5 Fit new rubber grommets to the brake master cylinder ports. 6 Press the fluid reservoir into the brake master cylinder ensuring that the rubber grommets do not become dislodged. 7 Reconnect the clutch master cylinder supply pipe, then tighten the union securely. 8 Fill the reservoir up the MAX marking with new brake fluid of the specified grade. 9 On completion, bleed the brake hydraulic system as described in Section 12. Check the operation of the braking system before using the vehicle on the road. Level sensor Removal 10.5 Master cylinder mounting nuts (arrowed) 3510 Vauxhall/Opel Omega 10 The sensor is integral with the brake fluid reservoir filler cap. Ensure that ignition key is turn to the Off position, then unplug the wiring from the sensor at the connector. 9 9•14 Braking system 11 Unscrew the cap from the reservoir and allow the excess fluid to drain off. Refitting 12 Refitting is a reversal of removal. After reconnecting the wiring, the operation of the sensor can be tested by suspending the reservoir cap above the reservoir, so that the float slides down to the end of its travel. The facia tell-tale warning lamp should illuminate. 12 Hydraulic system bleeding 3 Warning: Hydraulic fluid is poisonous; thoroughly wash off spills from bare skin without delay. Seek immediate medical advice if any fluid is swallowed or gets into the eyes. Certain types of hydraulic fluid are flammable and may ignite when brought into contact with hot components; when servicing any hydraulic system, it is safest to assume that the fluid is inflammable and to take precautions against the risk of fire as though it were petrol that was being handled. Hydraulic fluid is an effective paint stripper and will also attack many plastics. If spillage occurs onto painted bodywork or fittings, it should be washed off immediately, using copious quantities of fresh water. It is also hygroscopic i.e. it can absorb moisture from the air, which then renders it useless. Old fluid may have suffered contamination and should never be re-used. When topping-up or renewing the fluid, always use the recommended grade, and ensure that it comes from a new, sealed container. General information 1 The correct operation of any hydraulic braking system relies on the fact that the fluid used in it is incompressible, otherwise the effort exerted at the brake pedal and master cylinder will not be fully transmitted to the brake calipers or wheel cylinders. The presence of contaminants (such as air) in the hydraulic system will result in a spongy feel to the brakes and unpredictable performance, in 12.14a Remove the dust cap from the caliper bleed screw the form of brake fade or at worst brake failure. In addition, brake fluid deteriorates with age through oxidation and water absorption. This lowers its boiling point and may cause vaporisation under hard braking, again affecting brake performance. For this reason, old or contaminated brake fluid must be renewed regularly (see Chapter 1 for the service interval) - this is achieved by bleeding the entire system. Similarly, if you have disturbed any part of the hydraulic system during repair or servicing, the system must be bled to remove the air that will have been admitted. 2 When refilling the system, use only clean, new hydraulic fluid of the recommended type and grade; never re-use fluid that has already been bled from the system. Ensure that sufficient fluid is available before starting work. 3 If there is any possibility of there being incorrect fluid in the system already, the brake components and circuits must be flushed completely with new fluid of the correct type and grade and new seals should be fitted throughout the system. 4 If hydraulic fluid has been lost from the system, or air has entered because of a leak, ensure that the fault is corrected before proceeding further. 5 Park the vehicle on level ground, switch off the engine and select first or reverse gear (manual transmission) or Park (automatic transmission), then chock the wheels and release the handbrake. 6 Check that all pipes and hoses are secure, unions tight and bleed screws closed. Remove the dust caps and clean off all dirt from around the bleed screws. 7 Unscrew the master cylinder reservoir cap, and top the master cylinder reservoir up to the MAX level line; refit the cap loosely, and remember to maintain the fluid level at least above the MIN level line throughout the procedure, otherwise there is a risk of further air entering the system, as the level drops. 8 There are a number of one-man, do-ityourself brake bleeding kits currently available from motor accessory shops. It is recommended that one of these kits is used whenever possible, as they greatly simplify the bleeding operation, and also reduce the risk of expelled air and fluid being drawn back 12.14b Fit the spanner over the bleed screw and push the tube onto the bleed screw nipple 3510 Vauxhall/Opel Omega into the system. If such a kit is not available, the basic (two-man) method must be used, which is described in detail below. 9 If a kit is to be used, prepare the vehicle as described previously, and follow the kit manufacturer’s instructions, as the procedure may vary slightly according to the type being used. Generally, they are as outlined below in the relevant sub-section. 10 Whichever method is used, the same sequence must be followed to ensure the removal of all air from the system. Bleeding sequence Note: It is possible to partially bleed the system, i.e. just one brake line and caliper at a time. Providing fluid loss is kept to a minimum and air is not drawn into the system, it will not be necessary to bleed the other brake lines as well. Pre-1998 models with 3-channel ABS 11 Bleed the system in the following sequence:. 1 Front left hand brake 2 Front right hand brake 3 Rear left hand brake 4 Rear right hand brake Post-1998 models with 4-channel ABS 12 Bleed the system in the following sequence:. 1 Left-hand rear brake. 2 Right-hand front brake. 3 Right-hand rear brake. 4 Left-hand front brake. Bleeding basic (two-man) method 13 Obtain a clean glass jar, a suitable length of plastic or rubber tubing which is a tight fit over the bleed screw, and a ring spanner to fit the screw. Alternatively, a proprietary brake bleeding kit can be obtained. Note: The help of an assistant will also be required. 14 Remove the dust cap from the first caliper’s bleed screw. Fit the spanner over the bleed screw and push the tube onto the bleed screw nipple (see illustrations). Place the other end of the tube in the jar and pour in sufficient fluid to cover the end of the tube. 15 Throughout the procedure, keep an eye on the reservoir fluid level and ensure that it is maintained above the MIN level line as the brakes are bled; top it up before starting if necessary. 16 Have the assistant fully depress the brake pedal several times to build up pressure - then on the final downstroke, keep it depressed. 17 While pedal pressure is maintained, slacken the bleed screw (approximately one turn) and allow the brake fluid to flow into the jar. Pedal pressure should be maintained throughout; follow the pedal down to the end of its travel if necessary, but do not release it. When the flow stops, tighten the bleed screw again, then have your assistant release the pedal slowly. Re-check the reservoir fluid level and top it up if necessary. Braking system 9•15 18 If air is present in the brake lines, it will appear as bubbles in the expelled fluid. Repeat the steps given in the two previous paragraphs until the fluid emerging from the bleed screw is free from air bubbles. If the master cylinder has been drained and refilled and air is being bled from the first brake line in the sequence, allow several seconds between cycles for the master cylinder passages to refill. 19 When no more air bubbles appear, tighten the bleed screw securely, remove the tube and spanner then refit the dust cap. Caution: Do not overtighten the bleed screw. 20 Repeat the procedure on the remaining brake lines to be bled, until all air is removed from the system and the brake pedal feels firm again. Bleeding using a one-way valve kit 21 As their name implies, these kits consist of a length of tubing with a one-way valve fitted, to prevent expelled air and fluid being drawn back into the system; some kits include a translucent container, which can be positioned so that the air bubbles can be more easily seen flowing from the end of the tube. 22 The kit is connected to the bleed screw, which is then opened. The user returns to the driver’s seat, depresses the brake pedal with a smooth, steady stroke and slowly releases it; this process is repeated until the expelled fluid is free of air bubbles . 23 Note that the use of these kits can simplify the bleed operation so much, that it is easy to forget the reservoir fluid level. Ensure that it is maintained at least above the MIN level line at all times, or air may be drawn into the system. Bleeding using a pressure-bleeding kit 24 These kits are usually powered by pressurised air, such as that provided by the vehicle’s spare tyre. However, note that it will probably be necessary to reduce the tyre pressure to a lower level than normal before connecting to the bleeding kit; refer to the manufacturer’s instructions supplied with the kit. 25 The method involves connecting a pressurised, fluid-filled container to the master cylinder reservoir. Bleeding can then be carried out simply by opening each bleed screw in turn, and allowing the fluid to flow out under moderate pressure until no more air bubbles can be seen in the expelled fluid. 26 This method has the advantage that the large reservoir of fluid provides an additional safeguard against air being drawn into the system during bleeding. 27 Pressure-bleeding is particularly effective when bleeding difficult systems, or when bleeding the complete system at the time of routine fluid renewal. All methods 28 When bleeding is complete, and firm pedal feel is restored, wash off any spilt fluid, tighten the bleed screws securely, and refit their dust caps (where applicable). 29 Check the hydraulic fluid level in the master cylinder reservoir; top it up if necessary (see Weekly checks). 30 Dispose of any hydraulic fluid that has been bled from the system; it must not be reused. 31 Check the feel of the brake pedal. If it feels at all spongy, or has greater travel than expected, it is probable that air is still present in the system; further bleeding will therefore be required. If the bleeding procedure has been repeated several times and brake feel has still not been restored, the problem may be caused by air trapped in ABS hydraulic modulator. This can be dislodged by actuating the ABS return pump during the bleeding process, but note that this operation can only be carried out by a Vauxhall dealer with the necessary ABS diagnostic equipment. 13 Hydraulic brake lines and hoses removal and refitting 3 1 Remove the cap from the brake fluid reservoir and refit it with a piece of polythene sheeting covering the opening to help prevent subsequent loss of brake fluid. 2 Jack up the front or rear of the vehicle, as applicable, and support it on axle stands. Front flexible hose 3 Remove the front wheel. 4 Turn the steering on full lock. Unscrew the bolt securing the hose to the caliper and recover the copper washers. 5 Pull the locking plates from the mountings and disconnect the hose from the retaining clips. 6 Unscrew the rigid brake line union, and remove the hose. 7 Refitting is a reversal of removal, but make sure that the hose is not twisted or kinked. Bleed the hydraulic system as described in Section 12 . the brake lines can be obtained from motor accessory shops. 12 To remove a brake line, unscrew the unions at each end and release it from the clips. 13 Refitting is a reversal of removal. Bleed the hydraulic system as described in Section 12. 14 Vacuum servo hose and non-return valve renewal 3 1 When new, the vacuum hose is shrunk onto the non-return valve using a heat process, therefore when the valve is first renewed it is necessary to fit a conventional vacuum hose, using hose clips to secure the valve. Thereafter the hose and valve may be renewed separately. 2 Unscrew the hose union nut at the inlet manifold. 3 Pull or prise the elbow connector out of the servo. Note that some models may be equipped with a quick-release fitting. To disconnect the fitting, depress the catch at the side of the fitting and separate the two halves of the fitting. 4 Release the hose from the plastic straps. Where applicable, unplug the narrow-bore vacuum hose from the T-piece. 5 Cut the hose off the non-return valve, the elbow and the inlet manifold union. 6 Cut the new braided vacuum hoses to length (it is sold in 5.0 metre lengths) and secure to the non-return valve, elbow and union using proprietary clips. Make sure that the arrows on the valve point towards the inlet manifold end. 7 Press the elbow into the servo rubber grommet (or reconnect the quick-release union, as applicable) and tighten the union nut on the inlet manifold. Fit new plastic straps to secure the hose in position. Reconnect the narrow-bore vacuum hoses to the T-pieces. 8 Check the operation of the vacuum servo (see Section 15), then entire braking system, before using the vehicle on the road. 15 Vacuum servo unit testing, removal and refitting 3 Rear flexible hose 8 Pull the locking plates from the mountings. 9 Unscrew the rigid brake line unions, and remove the hose. 10 Refitting is a reversal of removal, but make sure that the hose is not twisted or kinked. Bleed the hydraulic system as described in Section12 . Brake lines 11 Some commonly-used brake lines can be obtained from GM parts stores already formed complete with unions, however other brake lines must be prepared from brake pipes of the required diameter. Kits for making 3510 Vauxhall/Opel Omega Testing 1 To establish whether or not the servo is operating, proceed as follows. 2 With the engine stopped, apply the brake pedal several times in order to dissipate the vacuum from the servo unit. 3 Hold the brake pedal depressed, then start the engine. The pedal should move a small distance towards the floor with the additional assistance of the servo unit. If not, check the vacuum hose and non-return valve. If these prove to be satisfactory, the servo unit itself is faulty and should be renewed. 9 9•16 Braking system Removal 4 Depress the footbrake pedal several times to dissipate the vacuum in the servo unit. 5 Disconnect the wiring for the brake fluid level warning lamp from the reservoir filler cap. 6 With reference to Chapter 12, remove both windscreen wiper arms from their respective shafts. 7 Carefully peel the rubber sealing strips from the rear edge of the engine compartment bulkhead, then remove the securing screws and withdraw the cowl panel from the lower edge of the windscreen. 8 Unscrew the master cylinder mounting nuts and pull the unit from the studs on the vacuum servo unit sufficiently to allow room for removal of the servo unit. Leave the brake lines connected to the master cylinder, but do not exert excessive force on the brake lines as this may cause them to fracture. 9 Pull or prise out the vacuum hose elbow connector, or unplug the quick-release connector, as applicable. Move the bulkhead wiring harness to one side. 10 Working inside the vehicle, in the driver’s footwell, remove the screws and lower the cover panel away from the underside of the facia. Unscrew the fixings and remove the footwell air ducting. 11 Unhook the return spring from the brake pedal. Remove the brake light switch from its mounting bracket (see Chapter 12, Section 4). 12 Extract the spring clip and pull out the clevis pin, to disconnect the servo pushrod from the brake pedal. 13 Unscrew the mounting nuts, then tilt the servo unit and remove it from the bulkhead into the engine compartment. Recover the gasket. Note that the nuts double up as the brake pedal bracket mounting nuts (see Section 16). 14 Loosen the locknut and unscrew the clevis fork from the pushrod. Unscrew the locknut. 15 Unscrew the nuts and remove the support bracket and gaskets from the servo unit. Refitting 16 Commence refitting by placing the support bracket together with a new gasket in position on the servo and tightening the securing nuts to the specified torque. 17 Screw the locknut and clevis fork onto the pushrod. With the pushrod in its rest position adjust the fork so that the distance between the servo support bracket face and the clevis pin centre line is 106.0 + 0.5 mm. Tighten the locknut to secure the fork in this position. 18 Refit the servo unit to the bulkhead using a new gasket. Fit the mounting nuts and tighten them to the specified torque. 19 Connect the pushrod to the brake pedal with the clevis pin and spring clip. 20 Reconnect the brake pedal return springs, then refit the brake light switch with reference to Chapter 12, Section 4. 21 Refit the footwell ventilation ducting and facia lower cover panelling. 22 Press the vacuum hose elbow connector in the servo rubber grommet, or reconnect the quick release fitting, as applicable. 23 If necessary, renew the O-ring seal on the master cylinder flange then locate the unit on the servo studs and tighten the mounting nuts (see Section 10 for details). 24 Press the brake pipes firmly into their retaining clips on the engine compartment bulkhead. 25 Reconnect the level sensor wiring to the brake fluid reservoir filler cap. 26 Refit the cowl panel to the lower edge of the windscreen, and secure it in position with the screws. 27 Press the rubber sealing strips into position at the rear of the engine compartment, then refit the windscreen wiper arms with reference to Chapter 12. 28 Test the operation of the vacuum servo as described at the beginning of this Section. Test the operation of the entire braking system before using the vehicle on the road. 16 Brake pedal removal and refitting 3 Removal 1 Working inside the vehicle, in the driver’s footwell, remove the screws and lower the cover panel away from the underside of the facia. Unscrew the fixings and remove the footwell air ducting. 2 Disconnect the wiring from the brake stop-lamp switch, then unclip the switch from the pedal bracket, noting its fitted position. 3 Unhook both the brake pedal return springs. 4 Extract the spring clip and pull out the clevis pin securing the servo pushrod to the brake pedal. 5 Slacken and withdraw the uppermost pedal bracket securing bolt. 6 Unscrew the nuts holding the pedal bracket to the bulkhead; note that these nuts double up as the servo mounting nuts (see Section 15). Pull the servo away from the bulkhead slightly, to withdraw the servo studs from pedal bracket. 7 Pivot the bracket downwards to release it from the upper servo studs then remove the bracket and pedal assembly from the vehicle. 8 Remove the spring clip, the unscrew the nut from the end of the pedal shaft, and remove the washer. 9 Remove the pedal location clips and carefully drive the shaft from the bracket, until the brake pedal can be removed. Recover the thrust washers (where fitted) and the centre spring (see illustration). Refitting 16.9 Brake pedal and associated components 1 Pedal bracket 2 Spring clip 3 Nut 4 Washer 5 Return spring 6 Pedal shaft 7 Pedal 3510 Vauxhall/Opel Omega 10 Refitting is a reversal of removal, but lubricate the pedal shaft with grease. Tighten all fixings to the specified torque where applicable. Refer to the information given in Chapter 12, Section 4 when refitting the brake light switch. Braking system 9•17 17 Anti-lock Braking System/ Traction Control system (ABS/TC) - information 4 Information 1 ABS is fitted as standard to all models. Traction control is fitted as standard to models with 6-cylinder engines. 2 The ABS system comprises a hydraulic modulator and electronic control unit together with four roadwheel sensors. The hydraulic modulator contains the electronic control unit (ECU), the hydraulic solenoid valves and the electrically-driven return pump. The purpose of the system is to prevent the road wheel(s) locking during braking. This is achieved by automatic adjustment of the hydraulic pressure applied to the brake on the wheel(s) that is/are about to skid. During normal operation, the system functions in the same way as a non-ABS braking system. In the event of ABS failure, the braking system reverts to conventional, non-ABS operation. 3 The solenoid valves are controlled by the ECU, which receives wheel rotation speed information from each of the four wheel speed sensors. By comparing these signals, the ECU can determine the speed at which the vehicle is travelling. It can then use this speed to determine when a wheel is decelerating at an abnormal rate, compared to the speed of the vehicle, and therefore predicts when a wheel is about to lock. 4 If the ECU senses that a wheel is about to lock, it operates the relevant solenoid valve(s) in the hydraulic unit, which then isolates from the master cylinder the relevant brake(s) on the wheel(s) which is/are about to lock, effectively sealing-in the hydraulic pressure. On models built before 1998 model year, the two front brakes are modulated separately, but the two rear brakes are modulated together via a shared hydraulic circuit. On later models, the hydraulic pressure to each caliper is modulated individually. 5 If the speed of rotation of the wheel continues to decrease at an abnormal rate, the ECU operates the electrically-driven pump which pumps the hydraulic fluid back into the master cylinder, releasing the brake. Once the speed of rotation of the wheel returns to an acceptable rate, the pump stops, and the solenoid valves switch again, allowing the hydraulic master cylinder pressure to return to the caliper/wheel cylinder (as applicable), which then re-applies the brake. This cycle can be carried out many times per second. 6 The action of the solenoid valves and return pump creates pulses in the hydraulic circuit. When the ABS system is functioning, these pulses can be felt through the brake pedal and the return pump can also be heard to operate. 7 On models with 6-cylinder models, the hydraulic unit incorporates an additional set of solenoid valves which operate the Traction Control (TC) system. The system operates at speeds up to approximately 30 mph (60 km/h) using the signals supplied by the wheel sensors. If the ECU senses that a driving wheel is about to lose traction, it prevents this by momentarily applying the relevant rear brake. 8 The operation of the ABS and the traction control system is entirely dependent on electrical signals. To prevent the system responding to any inaccurate signals, a builtin safety circuit monitors all signals received by the ECU. If an inaccurate signal or low battery voltage is detected, the system is automatically shut down, and the warning light on the instrument panel is illuminated, to inform the driver that the system is not operational. Normal braking is still available, however. Precautions a) Do not disconnect the ABS/TC control unit multiway harness plug with the ignition switched on. b) Do not use a battery booster to start the engine. c) Unplug the multi-way wiring connector from the ABS/TC control unit before carrying out any electrical welding on the car. d) Do not expose the unit to temperatures exceeding 80ºC (e.g. during paint-oven work). 18 Anti-lock Braking System/ Traction Control system component removal and refitting 4 Hydraulic modulator early models with (3-channel) ABS 2-SH or 2-SH/TC Removal 1 Disconnect the battery negative cable and position it away from the terminal. 2 Remove the cap from the brake fluid reservoir and refit it with a piece of polythene sheeting covering the opening to help prevent subsequent loss of brake fluid. 3 Unplug the wiring from the alarm system bonnet switch, then unscrew the bolt from the power steering reservoir clamp and tie the reservoir to one side. 4 Remove the ABS control unit as described later in this Section. Undo the securing screws and remove the ABS control unit mounting bracket from the modulator. 4-cylinder engined models 5 Identify all five brake lines on the modulator for location, then unscrew the union nuts and pull the brake lines just clear of the modulator. Be prepared for brake fluid leakage - place a suitable container underneath the unions before disconnection. If possible, plug the ends of the brake lines, or at least cover them to prevent excessive fluid brake fluid loss the ingress of dust and dirt. Also cover the hydraulic modulator ports. 3510 Vauxhall/Opel Omega 6 Slacken and remove the securing screws, then remove the heat shield from the modulator. 6-cylinder engined models 7 Identify the three uppermost brake lines on the modulator for location, then unscrew the union nuts and pull the brake lines just clear of the modulator. Be prepared for brake fluid leakage - place a suitable container underneath the unions before disconnection. If possible, plug the ends of the brake lines, or at least cover them to prevent excessive fluid brake fluid loss the ingress of dust and dirt. Also cover the hydraulic modulator ports. 8 Apply the handbrake, raise the front of the vehicle and rest it securely on axle stands. 9 Remove the engine compartment lower cover panel to allow access to the underside of the hydraulic modulator. 10 Slacken and remove the securing screws, then remove the heat shield from the modulator. 11 Identify the two lowermost brake lines on the modulator for location, then unscrew the union nuts and pull the brake lines just clear of the modulator. Again, be prepared for brake fluid leakage. All models 12 Unscrew the nut and disconnect the earth cable from the rear of the hydraulic modulator. 13 Unscrew the securing nuts from the hydraulic modulator guide pins, then move the brake lines carefully to one side and slide the modulator from the guide pins. 14 Remove the modulator from the engine compartment taking care to prevent brake fluid from running out of the modulator ports. 15 Check that the guide pin rubber mountings on the modulator are in good condition. No further dismantling of the hydraulic modulator is possible. Refitting 16 Refitting is a reversal of removal but tighten all nuts and bolts to the correct torque (where specified), and finally bleed the hydraulic system as described in Section 12. Check that the ABS warning light extinguishes at the first application of the brake pedal after starting the engine. On completion take the vehicle to a GM dealer and have the system’s operation verified with ABS test equipment. Hydraulic modulator and ABS/TC control unit later models with (4-channel) ABS 5.3 or 5.3/TC Removal 17 Disconnect the battery negative cable and position it away from the terminal. 18 Apply the handbrake, raise the front of the vehicle and support it securely on axle stands. 19 Undo the screws and lower the cover panel away from the underside of the engine compartment. 9 9•18 Braking system 18.46a Unscrew the mounting bolt . . . 18.46b . . . and withdraw the ABS sensor 18.51 ABS rear wheel speed sensors (arrowed) 20 Unscrew the fixings and remove the heat shield from the side of the hydraulic modulator. 21 With reference to Chapter 10 Section 26 disconnect the high pressure hydraulic fluid delivery pipe from the power steering pump. Position a container underneath the disconnected union to catch escaping hydraulic fluid. 22 Unclip the cover from the engine compartment auxiliary fusebox and detach the fuseholder from the base of the fusebox. 23 Unclip the cover from the engine compartment relay box. Withdraw the engine management system electronic control unit, then unplug the multiway connector from it; refer to Chapter 4A for details. 24 Release the engine management system relay from the relay box, together with its mounting bracket. 25 Disconnect the three main wiring harness plugs located at the rear of the main engine compartment fusebox. 26 Remove as much hydraulic fluid as possible from the power steering fluid reservoir, using an old (but clean) poultry baster or similar. 27 Slacken the hose clips and disconnect the two fluid hoses from the base of the power steering fluid reservoir. Place a suitable container underneath the reservoir to catch the hydraulic fluid that will run out. 28 Remove the power steering fluid reservoir from its mounting bracket then unbolt the bracket from the bodywork and remove it. 29 Undo the securing screw and unplug the multiway wiring harness connector from the ABS/TC control unit. 30 Remove as much hydraulic fluid as possible from the brake fluid reservoir, using an old (but clean) poultry baster or similar. 31 With reference to Section 10, undo the unions and disconnect the brake pipes from the side of the master cylinder. Place a suitable container underneath the reservoir to catch the brake fluid that will run out. Plug the ends of the brake lines. 32 Carefully label all six brake lines at the hydraulic modulator (to ensure that they are reconnected in correct order later) then unscrew the union nuts and pull the brake lines just clear of the modulator. Be prepared for brake fluid leakage - place a suitable container underneath the unions before disconnection. If possible, plug the ends of the brake lines, or at least cover them to prevent excessive fluid brake fluid loss, and the ingress of dust and dirt. Also cover the hydraulic modulator ports. 33 Detach the hydraulic modulator from its mounting bracket and remove it from the engine compartment, taking care to prevent brake fluid from running out of the modulator ports. Off position, then carefully prise the switch from the facia panel, using a small screwdriver. Use card or cloth to prevent damage to the facia. 41 Unplug the wiring connector from the rear of the switch. Refitting 43 Disconnect the battery negative lead. 44 Apply the handbrake, then jack up the front of the vehicle and support it on axle stands (see Jacking and Vehicle Support). Remove the relevant front roadwheel. 45 Disconnect the sensor wiring and release it from the clips on the front suspension strut and wheel arch. Do not confuse it with the brake pad wear sensor wiring connector. 46 Unscrew the mounting bolt using a Torx key and withdraw the sensor from the mounting bracket (see illustrations). 34 Refitting is a reversal of removal, noting the following points:. a) Tighten all nuts and bolts to the correct torque (where specified) b) Top up the power steering system with the correct grade of fluid as described in Weekly checks. c) Bleed the hydraulic system as described in Section 12. d) Check that the ABS warning light extinguishes at the first application of the brake pedal after starting the engine. e) On completion take the vehicle to a GM dealer and have the system’s operation verified with ABS test equipment. ABS/TC control unit early models with (3-channel) ABS 2-SH or 2-SH/TC Removal 35 Disconnect the battery negative cable and position it away from the terminal. 36 Unscrew the securing bolt and remove the cover panel from the ABS/TC control unit. 37 Unplug the three multiway wiring harness connectors from the ABS/TC control unit. 38 Slacken and remove the securing bolts and then lift the ABS/TC control unit away from the engine compartment. Refitting. 39 Refitting is a reversal of removal. On completion take the vehicle to a GM dealer and have the system’s operation verified with ABS test equipment. Traction Control switch Removal 40 Ensure that ignition key is turned to the 3510 Vauxhall/Opel Omega Refitting 42 Refitting is a reversal of removal. Front wheel speed sensors Removal Refitting 47 Refitting is a reversal of removal but smear a little anti-seize grease on the sides of the sensor casing before inserting it. On completion take the vehicle to a GM dealer and have the system’s operation verified with ABS test equipment. ABS rear wheel speed sensors Removal 48 Disconnect the battery negative lead. 49 Chock the front wheels, then jack up the rear of the vehicle and support it on axle stands (see Jacking and Vehicle Support). Remove the relevant rear roadwheel. 50 Disconnect the sensor wiring and release it from the clips on the underbody. 51 Unscrew the mounting bolt using a Torx key and withdraw the sensor from the final drive unit (see illustration). Refitting 52 Refitting is a reversal of removal but smear a little anti-seize grease on the sides of the sensor casing before inserting it into the final drive unit. On completion take the vehicle to a GM dealer and have the system’s operation verified with ABS test equipment. 10•1 Chapter 10 Suspension and steering Contents Front anti-roll bar - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 6 Front anti-roll bar drop link - removal and refitting . . . . . . . . . . . . . . 7 Front hub and bearings - removal and refitting . . . . . . . . . . . . . . . . . 9 Front lower suspension arm - removal and refitting . . . . . . . . . . . . . 4 Front suspension subframe - removal and refitting . . . . . . . . . . . . . . 10 Front suspension lower balljoint - renewal . . . . . . . . . . . . . . . . . . . . 5 Front suspension strut - camber adjustment . . . . . . . . . . . . . . . . . . 3 Front suspension strut - removal. overhaul and refitting . . . . . . . . . . 2 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Power steering pump - removal and refitting . . . . . . . . . . . . . . . . . . 27 Rear anti-roll bar - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 14 Rear axle (complete assembly) - removal and refitting . . . . . . . . . . . 17 Rear coil spring - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 13 Rear hub and bearing - removal and refitting . . . . . . . . . . . . . . . . . . 20 Rear semi-trailing arm - removal and refitting . . . . . . . . . . . . . . . . . . 12 Rear shock absorber - removal and refitting . . . . . . . . . . . . . . . . . . . 11 Rear suspension level control system - component removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Rear suspension subframe - removal and refitting . . . . . . . . . . . . . . 18 Rear suspension subframe mountings - renewal . . . . . . . . . . . . . . . 19 Rear suspension track control arm - removal and refitting . . . . . . . . 15 Steering column - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 22 Steering column lock/ignition switch - removal and refitting . . . . . . 23 Steering gear - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 24 Steering idler - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 26 Steering knuckle - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 8 Steering tie-rods - removal and refitting . . . . . . . . . . . . . . . . . . . . . . 25 Steering wheel - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 21 Wheel alignment - checking and adjustment . . . . . . . . . . . . . . . . . . 28 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications Front suspension Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Independent MacPherson struts, coil springs and anti-roll bar, double-acting telescopic shock absorbers. Adjustable camber. Rear suspension Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Independent, semi-trailing arms and coil springs, anti-roll bar, doubleacting telescopic shock absorbers. Adjustable track control arms. Steering Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Overall steering ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lubricant quantity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic fluid pressure: At full lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . At rest in centre position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Recirculating ball, worm shaft and nut with sector shaft and drop arm, adjustable track control rods. Hydraulic power-assistance on all models, Servotronic speed-sensitive power assistance on 6-cylinder models. 14.8:1 1.3 litres 100 to 110 bar 2 to bar 10 Front suspension Coil springs (typical): SOHC 4-cylinder engines up to 1998 . . . . . . . . . . . . . . . . . . . . . . . . . DOHC 4-cylinder engines, with air conditioning from 1998 . . . . . . . . 6-cylinder engines, without air conditioning, up to 1998 . . . . . . . . . . 6-cylinder engines, with air conditioning, from 1998 . . . . . . . . . . . . . Colour code Blue/Brown Blue/Orange Yellow/Lilac Brown/Brown 3510 Vauxhall/Opel Omega Spring length 368 mm 390 mm 362 mm 373 mm Compression rate 21 N/mm 21 N/mm 24 N/mm 24 N/mm 10•2 Suspension and steering Front wheel alignment* Camber: Saloon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Estate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum deviation, left to right wheel . . . . . . . . . . . . . . . . . . . . . . . . Castor: Saloon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Estate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maximum deviation, left to right wheel . . . . . . . . . . . . . . . . . . . . . . . . Toe-in: Saloon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Estate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Variation with inner wheel turned in at 20‡ . . . . . . . . . . . . . . . . . . . . . -1º40’ ± 45’ -1º40’ ± 45’ 1º 5º40’ ± 1º 5º ± 1º 1º 0º10’ ± 10’ 0º10’ ± 10’ 1º40’ ± 45’ Rear wheel alignment* Camber: Saloon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1º50’ ± 40’ Estate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1º40’ ± 40’ Maximum deviation, left to right wheel . . . . . . . . . . . . . . . . . . . . . . . . 45’ Toe-in: Saloon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0º20’ ± 10’ Estate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0º20’ ± 10’ Maximum deviation, left to right wheel . . . . . . . . . . . . . . . . . . . . . . . . 25’ *Note: Measurements taken and adjustments made with all tyres inflated to their fully laden pressures and the vehicle laden, i.e. a 70kg load in each front seat and a full tank of fuel. Wheels Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pressed steel or alloy 6 1/2 J x 15, 7J x 15 or 7J x 16, depending on model and specification. Tyres Sizes Saloon and estate models with 4-cylinder engines . . . . . . . . . . . . . . . . Saloon and estate models with 6-cylinder engines . . . . . . . . . . . . . . . . * Refer to vehicle handbook or Vauxhall dealer for tyre speed ratings. 195/65 R 15, 205/65 R 15 or 225/55 R 16 205/65 R 15 or 225/55 R 16 Pressures Refer to end of Weekly checks on page 0•17 Torque wrench settings Nm lbf ft 20 angle tighten through 30º angle tighten through 15º 65 65 15 Front suspension Anti-roll bar bearing bracket bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Anti-roll bar link rod to anti-roll bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Anti-roll bar link rod to strut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front subframe*: Front mounting bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Centre mounting bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear mounting bolts: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hub nut* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lower balljoint to arm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lower balljoint to knuckle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lower suspension arm pivot bolt:* Front: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 48 65 angle tighten through 30º angle tighten through 15º 48 150 angle tighten through 30º angle tighten through 15º 112 130 angle tighten through 30º angle tighten through 15º 320 35 100 96 120 angle tighten through 30º angle tighten through 15º 3510 Vauxhall/Opel Omega 236 26 74 89 Suspension and steering 10•3 Torque wrench settings (continued) Front suspension (continued) Lower suspension arm pivot bolt (continued):* Rear: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Strut damper rod nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Strut mounting nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Strut to steering knuckle:* Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear suspension Anti-roll bar drop link to semi-trailing arm . . . . . . . . . . . . . . . . . . . . . . . Anti-roll bar to subframe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Damping blocks to body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Damping blocks to subframe: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Driveshaft to rear hub: Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear hub nut* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Semi-trailing arm pivot bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Shock absorber lower mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Shock absorber upper mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Subframe to body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Subframe to differential damping bush . . . . . . . . . . . . . . . . . . . . . . . . . Track control arm to semi-trailing arm . . . . . . . . . . . . . . . . . . . . . . . . . . Track control arm to subframe* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering Airbag unit to steering wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Centre tie rod to drop arm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Centre tie rod to idler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Drop arm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel supply and return union nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Idler mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Outer tie-rod clamp bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Outer tie rods to centre tie rod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power steering pump: 4-cylinder engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-cylinder engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power steering pump hydraulic fluid union . . . . . . . . . . . . . . . . . . . . . . Power steering pump pulley . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering column . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering column support bracket nut . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering gear clamp bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering gear heat shields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering gear mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering pump support brackets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering shaft clamp bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tie-rod balljoint nut* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nm lbf ft 120 angle tighten through 30º angle tighten through 15º 70 55 89 52 41 90 angle tighten through 45º angle tighten through 15º 66 20 22 65 15 16 48 90 angle tighten through 30º angle tighten through 15º 66 50 angle tighten through 60º angle tighten through 15º 300 100 110 20 65 125 45 90 37 221 74 81 15 48 92 33 66 8 60 60 160 28 60 15 60 6 44 44 118 21 44 11 44 25 20 28 20 22 22 22 15 55 20 22 20 60 18 15 21 15 16 16 16 11 41 15 16 15 44 Wheels Wheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 81 *Use a new nut/bolt Note 1: As a general rule, any fastener which has been angle-tightened should be renewed. Note 2: The threads of all fasteners secured with locking compound must be thoroughly cleaned and, if necessary, re-cut to remove all traces of the old locking compound. Fresh locking compound should then be reapplied at reassembly. 3510 Vauxhall/Opel Omega 10 10•4 Suspension and steering 2.4a Pull out the retaining clip . . . 1 General description 1 The front suspension is of independent MacPherson strut type incorporating coil springs and double-acting telescopic shock absorbers. An anti-roll bar, connected to the suspension struts via drop links is mounted forward of the suspension arms. 2 The rear suspension is of independent type with coil springs, double-acting gas-filled telescopic shock absorbers, semi-trailing arms, anti-roll bar and adjustable track control arms. All components are mounted on a single subframe, which also houses the final drive unit (see Chapter 8 for general information relating to the final drive unit). 3 Power-assisted steering is fitted to all models, consisting of a recirculating ball and worm-type steering box with drop arm, a 2.7b . . . then unscrew . . . 2.8b . . . unscrew the upper mounting nut . . . 2.4b . . . and disconnect the hydraulic hose from the bracket on the strut 2.7a Mark the top of the steering knuckle in relation to the strut, to retain the camber setting . . . 1 Apply the handbrake, then jack up the front of the vehicle and support it on axle stands. 2 Remove the relevant front road wheel. 3 Remove the brake caliper from the steering knuckle, as described in Chapter 9. Support the caliper to avoid straining the brake hose. 4 Pull out the retaining clip and disconnect the hydraulic hose from the bracket on the strut (see illustrations). 5 Remove the ABS wheel speed sensor from the steering knuckle and disconnect the wiring with reference to Chapter 9. 6 Unscrew the nut and separate the bottom of the anti-roll bar link from the end of the anti-roll bar (see Section 7). To prevent the ball-pin from turning, hold it stationary with a spanner on the two flats provided. 7 Mark the top of the steering knuckle in relation to the strut, to retain the camber setting then unscrew and withdraw the strut lower securing bolts (see illustrations). Pull down on the lower suspension arm, to release the strut from the top of the steering knuckle. 8 Support the suspension strut by hand, then remove the cap, unscrew the upper mounting nut and remove the upper plate. Counterhold the damper rod with a second spanner to prevent it from rotating (see illustrations). 2.7c . . . and withdraw the strut lower securing bolts 2.8a Remove the cap . . . centre tie rod, idler arm and adjustable outer tie rods. 6-cylinder models are fitted with Servotronic speed sensitive power steering. 2 Front suspension strut removal and refitting 3 Warning: If you are renewing the strut as part of the overhaul procedure, both the left and right hand struts should be renewed as a pair, to preserve the handling characteristics of the vehicle. Removal 2.8c . . . and remove the upper plate 3510 Vauxhall/Opel Omega 2.8d Counterhold the damper rod with a second spanner to prevent it from rotating Suspension and steering 10•5 2.9 Withdrawing the front suspension strut from the wheel arch 2.11 Fitting the spring compressor to the strut coil spring 2.12a Hold the piston rod stationary with an Allen key . . . 2.12b . . . then unscrew the damper rod nut . . . 2.12c . . . and withdraw the washer renewed (in which case, the spring, upper mounting components, bushes, and associated components can be transferred to the new strut). 16 With the strut assembly now dismantled, examine all the components for wear, damage or deformation. Check the rubber components for deterioration. Renew any of the components as necessary. 17 Examine the shock absorber for signs of fluid leakage. Check the damper rod for signs of wear or corrosion along its entire length, and check the strut body for signs of damage or corrosion. While holding it in an upright position, test the operation of the strut by moving the damper rod through a full stroke, and then through short strokes of 50 to 100 mm. In both cases, the resistance felt should be smooth and continuous. If the resistance is jerky, or uneven, or if there is any visible sign of wear or damage to the strut, renewal is necessary. 18 If any doubt exists about the condition of the coil spring, carefully release the spring compressors, and check the spring for distortion and signs of cracking. Measure the unloaded height of the spring and compare it with the figure listed in the Specifications. 19 If a new shock absorber is being fitted, before reassembly push the damper rod fully into the shock absorber body, and then extend the rod to end of its travel. Do this three or four times to ensure that the shock absorber is fully primed. 20 Refit the rubber damper to the lower spring seat. Ensure that the coil spring is compressed sufficiently to enable the upper mounting components to be fitted, then lower the coil spring (together with the spring compressors) onto the lower spring seat, ensuring that the lower end of the coil spring abuts the stepped section of the rubber damper (see illustrations). Warning: Do not unscrew the damper rod nut (exposed by the removal of the upper mounting nut and plate) until spring compressors have been fitted to the suspension strut. 9 Pivot the lower end of the strut away from the wheel arch, then lower it away from the upper mounting and withdraw it from under the vehicle (see illustration). Overhaul Note: A purpose-made spring compressor is essential for this work. Use of makeshift or unsuitable tools may result in injury. 10 Remove the strut as described in the previous sub-Section. If required, mount it in a vice with padded jaws. 11 Fit the spring compressor and tighten it compress the coil spring, unloading the pressure on the upper seat and mounting (see illustration). 12 Hold the piston rod stationary with an Allen key, then unscrew the damper rod nut and withdraw the washer (see illustrations). 13 Remove the bearing and washer (noting its orientation), then slide off the upper spring seat, upper rubber damper, bump stop rubber and dust cover from the damper rod and from the top of the coil spring. Extract the rubber damper from the lower spring seat (see illustrations). 14 Lift off the coil spring together with the spring compressors. 15 It is not possible to separate the shock absorber from the strut body, so if the shock absorber is faulty the strut assembly must be 10 2.13a Remove the bearing . . . 2.13b . . . and washer . . . 3510 Vauxhall/Opel Omega 2.13c . . . then slide off the upper spring seat, upper rubber damper, bump stop rubber and dust cover 10•6 Suspension and steering 2.20a Refit the rubber damper to the lower spring seat 2.20b Lower the coil spring, together with the spring compressors, onto the lower spring seat 21 Locate the rubber damper in the upper spring seat, then slide the upper spring seat, bump stop rubber and dust cover over the damper rod (see illustration). 22 Ensure that the upper end of the coil spring abuts the stepped section of the rubber damper. 23 Fit the washer and strut bearing to the strut damper rod and secure them in position with the washer and a new damper rod nut. Hold the damper rod stationary using an Allen key and then tighten the nut to specified torque. A crow’s foot adapter may be required to allow the damper rod to be held still as the nut is tightened. 24 Slowly release the spring compressor and make sure that the coil spring locates correctly on the damping rings. 25 Refit the front suspension strut, as described in the following sub-Section. to the markings made on the steering knuckle during removal, to preserve the camber setting, then fit the new nuts, and tighten them to the specified torque. Note: If the original front wheel camber setting has been lost, or if new struts are being fitted, the camber setting must be checked and adjusted, using a camber gauge, before the strut lower nuts are tightened to their final torque setting; see Section 3 for details. 28 Reconnect the drop link to the end of the anti-roll bar and tighten the nut to the specified torque; see Section 7 for details. 29 Refit the ABS wheel speed sensor and reconnect the cable, with reference to Chapter 9. 30 Press the brake hydraulic hose into the bracket on the strut and secure with the metal retaining clip. Refit the brake caliper with reference to Chapter 9. 31 Refit the front wheel, then lower the vehicle to the ground and tighten the wheel bolts to the specified torque. 32 Finally, have the front wheel toe-in adjustment checked and if necessary adjusted. Refitting 26 Commence refitting by inserting the strut up into the upper mounting. Refit the upper plate, then fit a new securing nut. Tighten the nut to the specified torque whilst holding the piston rod stationary with an Allen key. A crow’s foot adapter may be required to allow the damper rod to be held still as the nut is tightened. 27 Fit the lower end of the strut to the steering knuckle and insert a pair of new securing bolts, noting that the bolts are inserted from the front of the strut, so that the heads face front of the car. Ensure that the lower end of the strut is positioned according 2.21 Locate the rubber damper in the upper spring seat 3 Front suspension camber adjustment 5 1 After disturbing the front suspension strut or any of the front suspension components that have an effect on wheel camber, the front wheel camber setting must be checked, and if necessary adjusted, to preserve the vehicle’s handling characteristics and to prevent uneven tyre wear. It is recommended that this operation is carried out by a Vauxhall dealer, who will have access to the necessary measuring equipment. However, the procedure is given here for reference. 2 Apply the handbrake, select first gear or Park (as applicable) then jack up the front of the vehicle and support it on axle stands. 3 Remove both front road wheels. 4 Remove both brake calipers from the steering knuckles, as described in Chapter 9. Support the calipers to avoid straining the brake hoses. 5 Working on one side of the vehicle, slacken and withdraw the front suspension strut lower 3510 Vauxhall/Opel Omega securing bolts. Fit two new securing bolts and nuts, noting that the bolts are fitted from the front of the strut so that their heads face the front of the car. 6 Set the wheel to maximum positive camber by pressing the top of the brake disc inwards, towards the engine compartment. The strut lower mountings bolts will pivot on their slotted mounting holes. Tighten the nuts to approximately 20 Nm only, then refit the brake caliper (see Chapter 9) and the road wheel. 7 Repeat the operations in paragraphs 5 and 6 on the opposite front wheel. 8 Carefully lower the vehicle to the ground and tighten the road wheel bolts to the specified torque. 9 Load the vehicle to its specified adjustment weight, as described in Specifications, Front wheel alignment. 10 Using a proprietary camber gauge, set the front wheels to the specified camber angle. Adjustments are made by grasping the top of the road wheel and pivoting the steering knuckle inwards or outwards to achieve the correct camber angle. 11 When the correct camber angles are obtained, tighten the strut lower mounting nuts progressively in two stages; first to 50 Nm, then to 90 Nm. 12 Release the handbrake and select neutral, then rock the vehicle on its road wheels to settle the suspension. 13 Recheck the camber setting; if further adjustment is required, repeat the operations described in paragraphs 2 to 12 inclusive. If no further adjustment is required, tighten the strut lower mounting nuts to their specified Stage 1 and Stage 2 torque settings. 4 Front lower suspension arm - removal and refitting 3 Removal 1 Apply the handbrake, then jack up the front of the vehicle and support it on axle stands. 2 Remove the relevant front road wheel. 3 Unscrew and remove the pinch-bolt, and pull down the lower suspension arm to release the balljoint from the steering knuckle. 4 Unscrew the vertical front mounting bolt and the horizontal rear mounting bolt, discard them, and withdraw the lower suspension arm from under the vehicle. Note the horizontal bolt head faces towards the rear of the car. Note also that access to the front mounting bolt is via the top of the suspension subframe and access is very limited due to the proximity of the engine mounting bracket. 5 Refer to Section 5 if renewing the suspension balljoint. Examine the rubber bushes in the arm and if necessary renew them using a hydraulic press. Note the orientation of the existing bushes in the lower arm before pressing them out, and ensure that the new bushes are fitted in the same way. Suspension and steering 10•7 10 Refit the front wheel and lower the vehicle to the ground. 11 Finally, have the front wheel alignment checked and if necessary adjusted. 5 Front suspension lower balljoint renewal 5.2 Drilling out the front suspension lower balljoint rivets Refitting 6 Commence refitting by locating the arm on the underbody and inserting the new mounting bolts. Do not re-use the old mounting bolts. Insert the front mounting bolt from back to front, and insert the (shorter) rear mounting bolt from top to bottom. 7 Hold the arm horizontally and tighten the securing nuts and bolts to the specified torque. 8 Insert the balljoint in the steering knuckle and fit a pinch-bolt, with its head facing the rear of the vehicle. Fit a new nut and tighten to the specified torque. 9 Reconnect the links to the anti-roll bar and tighten the nuts. 7.2a Unscrew the upper nut . . . 3 1 Remove the front lower suspension arm as described in Section 4. 2 The balljoint is riveted to the suspension arm when new, with subsequent balljoints bolted on. Where necessary drill out the rivets using a 12.0 mm drill. One side of each rivet has a centre punch to facilitate accurate drilling in order to prevent enlarging the holes in the arm (see illustration). 3 Coat the newly-drilled holes with a suitable rust-preventing agent. 4 Using only the special bolts supplied the new balljoint, fit the balljoint and tighten the nuts to the specified torque. The nuts must face downwards. 5 Refit the front lower suspension arm with reference to Section 4. 6 Front anti-roll bar removal and refitting 3 6.4 Unscrew the anti-roll bar mounting clamp bolts (arrowed) Refitting 6 Examine the mounting rubbers for wear and deterioration and, if necessary, prise them from the bar. Coat the new rubbers with a silicone-based spray and fit them on the bar with their slits facing towards the rear of the vehicle. 7 Insert the anti-roll bar from under the front of the vehicle, and refit the clamps. Insert the bolts loosely. 8 Reconnect the drop links to the ends of the anti-roll bar; use new securing nuts and tighten them to the specified torque. 9 Tighten the anti-roll bar mounting clamp bolts to the specified torque. 10 Refit the front wheels and lower the vehicle to the ground. Removal 1 Apply the handbrake, then jack up the front of the vehicle and support it on axle stands. Remove the front wheels. 2 Unscrew the nuts and separate the lower ends of the drop links from the ends of the anti-roll bar (see Section 7). Prevent the link ball-pins from turning by holding them with a spanner on the two flats provided. 3 Refer to Section 10 and remove the front suspension subframe. 4 From inside the engine compartment unscrew the anti-roll bar mounting clamp bolts, and unclip the clamps (see illustration). 5 Withdraw the anti-roll bar from under the vehicle. 7 Front anti-roll bar drop link removal and refitting 2 Removal 1 Apply the handbrake, then jack up the front of the vehicle and support it on axle stands. Remove the appropriate front wheel. 2 Note which way round the link is fitted then unscrew the nuts while holding the ball-pins with a spanner on the two flats provided (see illustrations). 3 Remove the link from the strut and anti-roll bar. 10 7.2b . . . and detach the drop link from the suspension strut 7.2c Detach the drop link from the anti-roll bar 3510 Vauxhall/Opel Omega 7.2d Counterhold the drop link stud using the flats provided 10•8 Suspension and steering 7.4 Tighten the anti-roll bar drop link securing nuts to the specified torque Refitting 4 Refitting is a reversal of removal but fit new securing nuts and tighten them to the specified torque (see illustration). 8 Steering knuckle removal and refitting 3 Removal 1 Remove the front hub as described in Section 9. 2 Unbolt the brake disc shield from the steering knuckle. 3 With reference to Section 24, unscrew the nut from the steering tie-rod balljoint, and use a proprietary balljoint separator to release the ball joint pin from the steering knuckle lug. 8.6a Unscrew and remove the pinch-bolt . . . 8.6b . . . and then lift the knuckle from the lower arm 4 Remove the ABS wheel speed sensor and disconnect the cable with reference to Chapter 9, Section 18. 5 Mark the top of the steering knuckle in relation to the strut in order to retain the camber setting, then unscrew and discard the bolts and separate the strut from the knuckle. Note that the bolt heads face forwards. 6 Unscrew and remove the pinch-bolt, and then lift the knuckle from the lower arm (see illustrations). the road wheel and lower the vehicle to the ground; with the road wheel in contact with the ground, it will be much easier to slacken the hub nut. 3 Chock the roadwheels securely, then using a socket, sturdy T-bar and a long extension bar for leverage, slacken the hub nut by about half a turn. Note that the nut is tightened to a very high torque setting, and considerable effort will be required to slacken it. 4 Jack up the front of the vehicle again and support it on axle stands. Remove the appropriate road wheel. 5 Remove the brake caliper and brake disc with reference to Chapter 9. 6 Fully unscrew and remove the hub nut, and pull the hub from the stub axle (see illustrations). If the inner bearing track remains on the stub axle, remove it with a universal bearing puller and recover the oil seal which will have been pulled out of the hub. Refitting 7 Refitting is a reversal of removal, but be sure to use new bolts and nuts. On no account should the old bolts be re-used. Tighten to the specified torque wrench settings and if necessary have the camber and wheel alignment checked by a Vauxhall dealer. 9 Front hub and bearings removal and refitting 4 1 Apply the handbrake, then jack up the front of the vehicle and support it on axle stands. Remove the appropriate front road wheel. 2 Lever the dust cap from the hub, then refit 7 The bearings cannot be renewed separately to the hub, so if the bearings are worn or the oil seal leaking the complete hub must be renewed. The new hub includes a plastic sleeve which holds the bearing inner tracks together while fitting the hub. 8 Locate the hub and plastic sleeve on the stub axle, then carefully drive the inner tracks onto the stub axle using a suitable size socket or metal tube (see illustration). Remove the plastic sleeve. 9.6c . . . and pull the hub from the stub axle 9.8 Carefully drive the hub onto the stub axle using a suitable socket Note: A torque wrench capable of measuring the high torque of the front hub nut should be obtained before commencing work. Removal 9.6a Fully unscrew . . . 9.6b . . . and remove the hub nut . . . Refitting 3510 Vauxhall/Opel Omega Suspension and steering 10•9 Refitting 9 Refit the components in the reverse order to removal, noting the following points (see illustration): a) Tighten all nuts and bolts to the specified torque. b) Use a new hub nut and ensure that it tightened to the specified torque c) Refit the brake disc and caliper as described in Chapter 9. d) Fit a new hub dust cap. 10 Front suspension subframe removal and refitting 3 9.9 Fitting a new hub dust cap lengths and diameters, then lower the subframe to the ground using the trolley jack. Removal Refitting 1 Apply the handbrake, then jack up the front of the vehicle and support it securely on axle stands. Unscrew the fixings and lower the cover panel away from the underside of the engine compartment. 2 On models with Xenon headlamps, unplug the wiring from the front vehicle level sensor; refer to Chapter 12, Section 13 for details. 3 Unbolt both lower suspension arm balljoints from the base of each steering knuckle, as described in Section 4. 4 Unbolt the anti-roll bar drop links from the ends of the anti-roll bar, as described in Section 7. 5 Unscrew the nuts securing both engine mountings to the subframe and engine brackets, with reference to Chapter 2A. Where applicable, also unbolt the engine vibration damper strut from the subframe. 6 Position an engine hoist or lifting beam over the engine compartment. Attach the lifting jib to the engine lifting eyelets at the side of the cylinder head(s) and raise it to take the weight of the engine. 7 Mark the relationship between the subframe and underbody using a marker pen to ensure correct alignment on refitting. 8 Support the weight of the subframe using a trolley jack and a stout length of wood. 9 Identify the six subframe mounting bolts for position. Progressively slacken and remove the bolts, noting that they are of different 10 Refitting is a reversal of removal, noting the following points: a) Refit the subframe according to the alignment markings made during removal. b) Fit new subframe securing bolts.. c) Tighten all nuts and bolts to the correct torque, where specified. d) On completion have the front wheel alignment (see Section 27) and camber setting (see Section 3) checked and if necessary corrected. 11 Rear shock absorber removal and refitting 3 Note: Shock absorbers should always be renewed as a pair, to preserve the handling characteristics of the vehicle. Removal 1 Chock the front wheels, then jack up the rear of vehicle and support it securely on axle stands. 2 Raise the relevant semi-trailing arm using a trolley jack to relieve the load on the shock absorber. 3 On Saloon models, remove the trim panel from the side of the boot space, then prise the rubber cap from the top of the shock absorber upper mounting. 4 On Estate models, fold back the load space carpet, then remove the screws and lift off the cover to expose the shock absorber upper mountings. 5 Unscrew the upper mounting nuts and remove the washer and rubber buffers (see illustration). 6 On models fitted with rear suspension level control, reach in through the rear wheel arch and release the air pressure from the valve on the side of the shock absorber body. Release the clip and disconnect the pressure line from the shock absorber. 7 Lower the semi-trailing arm using the trolley jack, then unscrew the lower mounting bolt and washer, then remove the shock absorber (see illustrations). 8 With the shock absorber removed, examine it for wear, damage or deformation. Check the rubber mounting components for deterioration. Renew any of the components as necessary. 9 Examine the shock absorber for signs of fluid leakage. Check the damper rod for signs of wear or corrosion along its entire length, and check the strut body for signs of damage or corrosion. While holding it in an upright position, test the operation of the shock absorber by moving the damper rod through one or two full strokes, and then through short strokes of about 50 to 100 mm. In both cases, the resistance felt should be smooth and continuous. If the resistance is jerky, or uneven, or if there is any visible sign of wear or damage to the strut, renewal is necessary. 10 If a new shock absorber is being fitted, before reassembly push the damper rod fully into the shock absorber body, and then pull the rod out to end of its travel. Do this three or four times to ensure that the shock absorber is fully primed. Refitting 11 Commence refitting by locating the shock absorber on the semi trailing arm and inserting the bottom mounting bolt loosely. Ensure that the bush engages with the recess in the lower mounting. 12 Raise the semi-trailing arm using a trolley jack and guide the top of the shock absorber through its upper wheel arch mountings. 10 11.5 Unscrew the rear shock absorber upper mounting nut 11.7a Unscrew the rear shock absorber lower mounting bolt and washer . . . 3510 Vauxhall/Opel Omega 11.7b . . . then remove the shock absorber from the wheel arch 10•10 Suspension and steering 13 On models with rear suspension level control, charge the shock absorber slightly with compressed air. An exact initial pressure is not specified by the manufacturer but carefully inflate the shock absorber until it protrudes through the upper mountings. Refit the pressure line to the shock absorber valve and secure it in position with the retaining clip. Ensure that the pressure line is positioned so that it does not foul any suspension components. 14 Refit the upper mounting rubber buffers and washer. Fit a new securing nut and tighten it to the specified torque. 15 Tighten the lower shock absorber mounting bolt to the specified torque. 16 On estate models, refit the cover panel and secure it position with the screws. 17 On Saloon models, press the rubber cap onto the top of the shock absorber. 18 Refit the road wheels and lower the vehicle to the ground. 19 Carry out a check of the rear suspension level control system’s operation, where applicable. 12 Rear semi-trailing arm removal and refitting 3 Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support on axle stands positioned under the subframe mountings. 2 With reference to Chapter 8, Section 8, unbolt the relevant driveshaft from the rear hub and support it to one side. 3 Disconnect the hydraulic brake hose from the bracket on the semi-trailing arm. 4 Remove the rear brake caliper and brake disc as described in Chapter 9. 5 Unhook the return spring and disconnect the handbrake cable from the lever on the semi-trailing arm. Disconnect the cable from the bracket. 6 On models with rear suspension level control, unplug the wiring from the rear vehicle level sensor. Mark the relationship between the level sensor actuator arm and the anti-roll bar drop link, to ensure correct alignment on refitting, then prise the link rod from the balljoint on the sensor actuator arm. 7 Using a socket through the unthreaded holes in the hub unscrew the brake anchor plate bolts and remove the locking plate. 8 Remove the rear hub with reference to Section 20, then withdraw the brake anchor plate and brake shoes as an assembly. 9 Unbolt the track control arm from the semitrailing arm, with reference to Section 15. 10 With reference to Chapter 4A, disconnect the mounting rubbers from the exhaust system intermediate and rear silencers, then lower the exhaust system away from the floorpan by approximately 30 cm. Support the exhaust in this position with wire or nylon cable ties. 11 Unbolt the rear anti-roll bar drop link from the semi-trailing arm. Pivot the link upwards to keep it clear of the work area. 12 Raise the semi-trailing arm slightly using a trolley jack, to relieve the load on the shock absorber. 13 On models fitted with rear suspension level control, release the air pressure via the shock absorber valve by disconnecting the pressure line from the shock absorber (see Section 11). 14 Unscrew and withdraw the shock absorber lower mounting bolt with reference to Section 11. 15 Lower the semi-trailing arm using the trolley jack until the rear coil spring and damping rubbers can be removed (see Section 13). 16 Position a trolley jack underneath the final drive unit, the raise the jack head until it is just support the weight of the unit. 17 Remove the heat shield panels, then with reference to Chapter 8, unbolt the propeller shaft centre bearing support bracket from the underbody. Support the propeller shaft on an axle stand. 18 Slacken and remove the bolts securing the leading edge of the rear subframe to the floorpan. Lower the final drive unit and subframe slightly, using the trolley jack, until the semi-trailing arm bolts are accessible. 19 Slacken and withdraw the pivot bolts and remove the semi-trailing arm from the subframe. 20 If the pivot bushes are worn, they may be renewed. Cut the shoulders from the old bushes and press them from the semi-trailing arm using a hydraulic press. Fit the new bushes in a similar way, but dip them in soapy water first to assist fitting. Note that the plasticcoated bush, nearest the final drive unit, is fitted with its collar facing the final drive unit. Refitting 21 Refitting is a reversal of removal, noting the following points. a) Tighten all nuts and bolts to the specified torque. b) The semi-trailing arm pivot bolt must be inserted such that their heads face away from final drive unit. c) On vehicles with rear suspension level control, refit the level sensor connecting rod with respect to the alignment markings made during removal. d) When reconnecting the pressure line to the shock absorber on models with rear suspension level control, ensure that the line cannot be fouled by any of the suspension components. e) On models with Xenon headlamps, reconnect the wiring to the vehicle level sensor. 22 On completion adjust the handbrake with reference to Chapter 1, then have the rear wheel alignment checked and if necessary adjusted by a Vauxhall dealer. On models with Xenon headlamps, it is also recommended that the headlight beam alignment is checked by a Vauxhall dealer. 3510 Vauxhall/Opel Omega 13 Rear coil spring removal and refitting 3 Note: Suspension coil springs should always be renewed as a matched pair, to preserve the handling characteristics of the vehicle. Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support on axle stands. Remove the relevant rear wheel. 2 Disconnect the hydraulic brake hose from the bracket on the semi-trailing arm by pulling out the locking plate. 3 With reference to Chapter 4A, disconnect the mounting rubbers from the exhaust system intermediate and rear silencers, then lower the exhaust system away from the floorpan by approximately 30 cm. Support the exhaust in this position with wire or nylon cable ties. 4 On models with rear suspension level control, unplug the wiring from the rear vehicle level sensor. Mark the relationship between the level sensor actuator arm and the anti-roll bar drop link, to ensure correct alignment on refitting, then prise the link rod from the balljoint on the sensor actuator arm. 5 Using a trolley jack, slightly raise the semi-trailing arm to relieve the load on the shock absorber. 6 On models fitted with rear suspension level control, release the air pressure via the shock absorber valve by disconnecting the pressure line from the shock absorber (see Section 11). 7 Unbolt the lower end of the shock absorber with reference to Section 11. 8 Unclip the ABS rear wheel speed sensor cables from the underbody, then unplug the cables from the sensor at the connectors; see Chapter 9 for details. 9 Using a trolley jack, support the final drive unit then unbolt the subframe rear damping brackets from the underbody (see Section 19). 10 Lower the final drive unit, subframe and semi-trailing arm until the rear coil spring and damping rubbers can be removed. Note that the upper damping rubber incorporates a buffer. Refitting 11 Refitting is a reversal of removal, noting the following points. a) When refitting the coil spring, ensure that the end face of the top of the coil is facing the rear of the vehicle. b) Tighten all nuts and bolts to the specified torques. c) On vehicles with rear suspension level control, refit the level sensor connecting rod with respect to the alignment markings made during removal. d) Refit the ABS wheel speed sensors with reference to Chapter 9. Suspension and steering 10•11 14 Rear anti-roll bar removal and refitting Pressure line 3 Removal Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support securely on axle stands. 2 On models with rear suspension level control, mark the relationship between the level sensor actuator arm and the anti-roll bar drop link, to ensure correct alignment on refitting, then prise the link rod from the balljoint on the sensor actuator arm. 3 Disconnect the wiring from the ABS wheel speed sensors, then release the wiring from the clips on the rear subframe. 4 Unbolt the two anti-roll bar drop links from the ends semi-trailing arms, and remove the rubber mountings (see illustration). 5 Support the final drive unit on a trolley jack. Unbolt the subframe rear damping brackets from the underbody, then lower the final drive unit slightly, until access to the anti-roll bar mounting clamp bolts can be gained. 6 Unscrew the clamp bolts from the top of the subframe and release the clamps from the anti-roll bar. Pass the anti-roll bar over the rear of the subframe and withdraw it together with its drop links from under the vehicle. 7 Unbolt the drop links from the anti-roll bar. If necessary, the clamp mounting rubbers may be pressed from the links and renewed, using a hydraulic press. Dip the new rubbers in soapy water to assist fitting them. Refitting 8 Refitting is a reversal of removal, but tighten all nuts and bolts to their correct torques, where specified. 15 Rear track control arm removal and refitting 3 14.4 Rear anti-roll bar-to-drop link bolt nuts/bolts where indicated in the Specifications. Tighten all fixings to the specified torque. On completion, have the rear wheel alignment checked and if necessary adjusted by a Vauxhall dealer. 16 Rear suspension level control system - component removal and refitting 3 Compressor Removal 1 The compressor is located in the right hand front wheel arch. To gain access, raise the front of the vehicle and rest it securely on axle stands. Remove the right hand roadwheel, the unscrew the fixings and detach the liner from the right hand wheel arch. 2 Unplug the wiring connector from the compressor. 3 Disconnect the air intake hose from the cavity behind the right hand headlight unit. 4 Release the securing clip and detach the air pressure pipe from the top of the compressor. 5 Slacken and withdraw the securing screws then remove the compressor together with its mounting bracket from the bodywork. Refitting Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support securely on axle stands. 2 Unscrew the nut securing the track control arm to the semi-trailing arm (see illustration). Disconnect the rod from the arm using a proprietary ball joint separator. 3 Unbolt the track control arm from the subframe (see illustration), and remove the arm from the vehicle. 4 If the track control arm is to be dismantled, first measure its overall length to obtain an approximate rear wheel alignment setting after refitting. 6 Refitting is a reversal of removal. On completion, check the operation of the level control system as described in the last subSection. 7 Disconnect the pressure line from the compressor as described in the previous subSection. 8 Raise the rear of the vehicle and rest it securely on axle stands. 9 Release the metal spring clip and disconnect the pressure line from the valve on the side of the first rear shock absorber. Disconnect the pressure pipe from the opposite shock absorber in a similar manner. 10 Locate the pressure T-piece which is mounted on vehicle underbody. Release the clips and disconnect the pressure pipe from the T-piece. 11 Work along the underside of the vehicle, releasing the pressure pipe from its securing clips, then remove the pipe from the vehicle. Refitting 12 Refitting is a reversal of removal. When refitting the pressure pipes to the rear shock absorbers, ensure that they are positioned such that they cannot be fouled by the rear suspension components. On completion, check the operation of the level control system as described in the last sub-Section. Level sensor Removal 13 Disconnect the battery negative cable and position it away from the terminal. 14 Chock the front wheels, then raise the rear of the vehicle and support it securely on axle stands. Remove the rear road wheels. 15 Unplug the wiring from the level sensor at the multiway connector. 16 Prise the connecting rod from the balljoint on the sensor’s actuator arm. 17 Undo the securing screws and remove the sensor together with its bracket from the subframe. Refitting 18 Refitting is a reversal of removal. On completion, check the operation of the level control system as described in the next subSection. System operation check 19 Park the vehicle (unloaded) on level 10 Refitting 5 Refit the track control arm by following the removal procedure in reverse, using new 15.2 Track control arm-to-semi-trailing arm bolt 3510 Vauxhall/Opel Omega 15.3 Track control arm-to-subframe bolt 10•12 Suspension and steering ground. Release the handbrake and let the engine idle for while, to allow the rear suspension ride height to stabilise. Re-apply the handbrake. 20 Measure the vertical distance from the ground to a convenient point on the rear bumper. 21 Place a heavy load in the boot/load space. Release the handbrake and let the engine idle for while, to allow the rear suspension ride height to stabilise. Re-apply the handbrake. 22 Repeat the measure carried out in paragraph 20. If operating correctly, the rear suspension control system should control the loaded ride height to a value 3 to 5 cm less than the unloaded ride height within 20 seconds. 23 Remove the load and allow the rear ride height to stabilise again. The system should return the ride height to the original unloaded ride height within 20 seconds. 17 Rear axle (complete assembly) removal and refitting 4 Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support it on axle stands. Position the axle stands such access can still be gained to all the rear subframe mounting bolts. Remove both rear road wheels. 2 Remove the intermediate and rear sections of the exhaust system with reference to Chapter 4A. 3 Note the position of the adjustment nut on the handbrake rod, then unscrew it and slide off the compensator bar; see Chapter 9, Section 8. 4 With reference to Chapter 9, unbolt both rear brake calipers from the semi-trailing arms and support them away from the disc, taking care not to damage the rigid brake lines. 5 Release the handbrake cables and hydraulic brake hoses from the brackets on both semi-trailing arms. 6 On models with Xenon headlamps, unplug the wiring from the rear vehicle level sensor; see Chapter 12 Section 13. 7 Unbolt the ABS wheel speed sensors from the final drive unit, with reference to Chapter 9, Section 18. 8 At the rear of the propeller shaft unscrew the bolts securing the rear disc joint to the differential flange. 9 Position a length of wood beneath the semi-trailing arms and support in the middle with a trolley jack. 10 Unbolt the final drive unit rear damping brackets from the underbody and lower the unit onto the length of wood. 11 Unscrew the shock absorber bottom mounting bolts on each side. 12 Lower the trolley jack until both rear coil springs and damping rubbers can be removed. Note that the upper damping rubbers incorporate buffers. 13 Raise the trolley jack until the rear damping bracket touches the underbody, then unscrew the three bracket bolts and centre bolt from the subframe front mountings (see illustration). As a precaution, have an assistant steady the assembly to prevent it falling from the trolley jack. 14 Lower the rear axle assembly to the ground and withdraw from under the vehicle. Be prepared to support the propeller shaft as it releases from the final drive unit. Refitting 15 Refitting is a reversal of removal, noting the following points. a) Tighten all nuts and bolts to the correct torque settings, where specified. b) Adjust the handbrake with reference to Chapter 1. c) On completion it is recommended that the rear wheel alignment is checked and if necessary corrected by a Vauxhall dealer. 17.13 Unscrew the three bracket bolts (A) and centre bolt (B) from the subframe front mountings 3510 Vauxhall/Opel Omega 18 Rear suspension subframe removal and refitting 3 Removal 1 Remove the rear axle assembly as described in Section 17. 2 Unscrew the anti-roll bar clamp bolts from the top of the subframe and release the clamps. 3 Unscrew the final drive unit mounting bolts and lower the unit from the subframe. 4 Unscrew and remove the semi-trailing arm pivot bolts, noting that the bolt heads are facing each other on each arm. Remove the subframe. 5 If necessary renew the mountings with reference to Section 19. Refitting 6 Refitting is a reversal of removal, but tighten all nuts and bolts to the specified torques. The semi-trailing arms should be positioned horizontally before tightening the pivot bolts. 19 Rear suspension subframe mountings renewal 2 Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support on axle stands positioned under the rear underbody channel sections. Remove both rear wheels. 2 Disconnect the exhaust rear mounting rubbers and lower the exhaust approximately 30 cm. Temporarily support the exhaust in this position with wire or nylon cable ties. 3 Disconnect the hydraulic brake hoses from the brackets on the semi-trailing arms by pulling out the locking plates. 4 Support the final drive unit on a trolley jack. 5 Unscrew the three bracket bolts and one centre bolt from the subframe mountings on each side and remove the brackets. 19.6 Withdrawing the subframe mountings Suspension and steering 10•13 6 The mountings must now be pulled from the subframe. The Vauxhall tool for this task is shown in (see illustration). The subframe is lowered slightly and the mounting bolt inserted from the top, then the puller is assembled as shown and the nut tightened to withdraw the mounting. If a similar arrangement using a conventional puller is not possible, use metal tubing, a long bolt, and large washers or a metal plate to remove the mounting. 7 The Vauxhall tool for inserting the mountings is shown in (see illustration), and here again a similar tool may be fabricated from metal plate and a long bolt. 21 Steering wheel removal and refitting Models without driver’s airbag Removal Refitting 8 Refitting is a reversal of removal. 19.7 Pressing in the subframe mountings 20 Rear hub and bearing removal and refitting 12 Extract the circlip from the semi-trailing arm then press out the bearing, again using a bearing puller bolted to the arm. 13 If the inner bearing track has remained on the hub remove it with a bearing puller. 14 Clean all the components and examine them for wear and damage. Obtain a new bearing. 4 Note: A torque wrench capable of measuring the high torque of the rear hub nut should be obtained before commencing work. If such a torque wrench is not available, it is recommended that the work is entrusted to a Vauxhall dealer. Removal 1 Chock the front wheels, then jack up the rear of the vehicle and support it on axle stands. 2 Unscrew the socket-head bolts securing the driveshaft to the rear hub while holding the rear wheel stationary. Recover the lockwashers. 3 Lever the driveshaft from the rear hub and support it to one side. 4 Remove the rear wheel. 5 Disconnect the hydraulic brake hose from the bracket on the semi-trailing arm by pulling out the locking plate. 6 Unbolt and remove the brake caliper and support it to one side without straining the hydraulic brake hose Unscrew the retaining screw and remove the brake disc. Refer to Chapter 9 for details of both operations. 7 Refer to Chapter 10 and unbolt the shock absorber lower mounting bolt from the semi-trailing arm. Support the semi-trailing arm on the head of a trolley jack. 8 Using an Allen key through an unthreaded hole in the hub drive flange, unscrew the brake backplate mounting bolts. Note that the upper bolts are shorter and are fitted with a locking plate. 9 Insert the wheel bolts and use a long bar to hold the hub stationary, then remove the locking plate and unscrew the central hubsecuring nut (exposed by the removal of driveshaft) from the rearward-facing surface of the hub (see illustration). 10 Pull off the driveshaft flange using a suitable puller. 11 Press the rear hub outwards from the bearing using a suitable puller bolted to the semi-trailing arm. 3 Refitting 15 Press the new bearing into the semi-trailing arm using pressure on the outer track. If necessary, a long bolt and a selection of flat washers may be used to do this. 16 Fit the bearing retaining circlip. 17 Support the wheel bearing inner track on the inside with a metal tube, then carefully drive in the rear hub from the outside. 18 Fit the driveshaft flange on the inside of the hub. If necessary, support the outside of the hub and drive the flange fully on from the inside. 19 Refit the hub nut and tighten to the specified torque while holding the hub stationary. Drive in the special locking plate to secure the nut in position. 20 The remainder of the refitting procedure is a reversal of removal, but note the following points. a) Tighten all nuts and bolts to the specified torque wrench settings b) Adjust the handbrake with reference to Chapter 1. 20.9 Driveshaft flange and rear hub nut 3510 Vauxhall/Opel Omega 1 Disconnect the battery negative lead. 2 Set the front wheels in the straight-ahead position. 3 Prise the horn pad from the centre of the steering wheel and disconnect the two wires. 4 With the ignition key inserted check that the steering lock is disengaged. 5 Bend back the locktab and unscrew the retaining nut. Remove the locktab. 6 Mark the inner column and steering wheel in relation to each other then remove the steering wheel by carefully rocking it from side to side. Do not use a hammer or mallet to remove it. 7 If necessary, unclip the horn contact ring from the steering wheel, noting that the direction indicator return segment points to the left. 8 Check that the spring is located on the inner column, and lightly lubricate the horn contact finger with a copper-based grease. Refitting 9 Refitting is a reversal of removal, but tighten the nut to the specified torque and bend up the locktab to lock the nut in position. Models with driver’s airbag Warning: Refer to the Supplementary Restraint System (SRS) precautions given in Chapter 12 before disturbing the driver’s airbag. Removal 10 Before removing the driver’s airbag, carry out the following operations: disconnect the negative cable from the battery and position it clear of the terminal. Wait at least one minute before proceeding, to allow the SRS control unit capacitor to discharge. Failure to observe these steps may result in accidental detonation of the airbag. 11 Remove the driver’s airbag from the steering wheel, as described in Chapter 12, Section 24: Supplementary Restraint System (SRS) components - removal and refitting. 12 Set the steering wheel in the straight ahead position, then remove the ignition key and allow the steering column lock to engage. Ensure that the steering column remains in this position throughout the entire procedure. 13 Mark the relationship between the steering wheel and column to ensure correct alignment on refitting. 14 Unplug the horn button wiring at the multiway connector. Where applicable, also unplug the audio remote control button wiring (see illustration). 10 10•14 Suspension and steering 21.14 Unplug the horn button/audio control wiring at the multiway connector(s) 21.15a Bend back the locktab . . . 21.15b . . . and then slacken . . . 21.15c . . . and remove the steering wheel retaining nut . . . 21.15d . . . and remove the locktab 21.16a Remove the steering wheel from the steering column 15 Bend back the locktab and then unscrew the steering wheel retaining nut. Remove the locktab (see illustrations). 16 Remove the steering wheel from the steering column by carefully rocking it from side to side. Do not use a hammer or mallet to remove it. Guide the horn and audio control wiring through the aperture at the centre of the steering wheel (see illustrations). to the flexible joint, then unscrew and remove the upper clamp bolt, to separate the end of the inner section of the steering column from the flexible joint (see illustration). 3 Remove the steering wheel as described in Section 21. On models fitted with a driver’s airbag, remove the airbag contact unit, with reference to Chapter 12, Section 24. Warning: Refer to the precautions given in Chapter 12 before disturbing the any of Supplementary Restraint System (SRS) components. Refitting 21.16b If necessary, use a proprietary steering wheel puller to assist removal 17 Refitting is a reversal of removal, but tighten the nut to the specified torque and bend up the locktab to lock the nut in position. Refit the driver’s airbag with reference to Chapter 12, Section 24: Supplementary Restraint System (SRS) components - removal and refitting. 22 Steering column removal and refitting 4 Removal 22.2 Unscrew and remove the upper clamp bolt (arrowed) to separate the inner section of the steering column from the flexible joint 1 Park the vehicle on level ground with the steering wheel turned to the straight-ahead position. Disconnect the battery negative lead. 2 Working in the driver’s footwell, release the clip and screws and detach the lower trim panel from underside of the facia. Mark the inner section of the steering column in relation 3510 Vauxhall/Opel Omega 4 Where applicable, unscrew the shaft from steering column height adjustment lever. 5 Remove the screws and withdraw the upper and lower shroud panels from the steering column. 6 Remove the steering column lock cylinder with reference to Section 23. 7 Remove the ignition switch contact unit with reference to Section 23. 8 Depress the locking clips and remove the stalk switch units from the steering column; refer to Chapter 12, Section 4. 9 At the lower edge of the facia, below the steering column, release the securing clip and hinge the access panel downwards away from the fuse box and relay box. Remove the screws, unhook the check strap and remove the lid from the facia. 10 Slacken and withdraw the securing screws, then release the fuse box and relay box from the facia, leaving the wiring harnesses connected. Suspension and steering 10•15 22.11 Steering column upper mounting nut (A) and shear bolt (B) 11 The upper column mounting consists of a nut and a shear bolt (see illustration). Ideally a bolt extractor should be used to remove the shear bolt by first drilling a 3.2 mm hole then using the extractor to unscrew the bolt. Alternatively, drill off the head and use grips to unscrew the remainder of the bolt later. 12 Unscrew the upper mounting nut and withdraw the steering column rearwards from the flexible coupling. The column should be handled carefully to avoid damage to the latticed safety outer column and special inner column. Refitting 13 Refitting is a reversal of removal but tighten all nuts and bolts to the specified torque. Before tightening the shear bolt, check that the column is correctly aligned then tighten the bolt until the head shears off. Check that, with the front wheels in the straight-ahead position, the steering wheel spokes are centred. Before tightening the clamp bolt, check that the steering column is not stressed, then tighten the bolt to the specified torque. Make sure that the switch rubber grommets are correctly located in the upper shroud. 23.3 Slide the immobiliser receiver from the lock cylinder housing 23 Steering column lock/ignition switch removal and refitting 3 Lock cylinder Removal 1 Remove the steering wheel as described in Section 21. 2 Slacken and withdraw the screws, then detach the upper lower sections of the shroud panelling from the steering column. 3 Unplug the wiring and slide the immobiliser receiver from the lock cylinder housing (see illustration). 4 Insert the ignition key into the lock cylinder and turn it to position I. 5 Depress the recessed locking button with a suitable tool and withdraw the lock cylinder, together with the key from, from the housing (see illustrations). Refitting 6 Before inserting the lock cylinder into its housing, check that the steering lock bolt has not engaged; if this is the case, it will not be possible to fully insert the lock cylinder into the housing. Correct this condition by inserting a flat bladed screwdriver into the housing and pressing the locking button latch downwards, until the bolt disengages (see illustration). 7 Slide the lock cylinder into its housing, until the locking bolt engages. 8 Where applicable, slide the immobiliser receiver into position over the lock cylinder housing and reconnect the wiring. 9 Refit the steering column shroud panelling and tighten the screws securely. 10 Reconnect the battery negative cable. Ignition switch contact unit Removal 11 Remove the lock cylinder as described in the previous sub-Section. 12 Unplug the multiway connector from the rear of the switch contact unit. To release the connector, depress the locking tab at the centre of the connector body using a thin flat bladed screwdriver (see illustration). Carefully prise the connector from the contact unit by gently levering between them with a screwdriver - take care to avoid damaging the connector terminals. 10 23.5a Depress the recessed locking button with a suitable tool . . . 23.5b . . . and withdraw the lock cylinder, together with the key from, from the housing 3510 Vauxhall/Opel Omega 23.6 If necessary, press the locking button latch (arrowed) downwards, until the steering lock bolt disengages 10•16 Suspension and steering 23.12 Depress the connector body locking tab and unplug connector from the rear of the ignition switch contact unit 13 Depress the locking button using a suitable tool and withdraw the contact unit from the rear of the lock cylinder housing (see illustrations). Refitting 14 Refitting is a reversal of removal. 24 Steering gear removal and refitting 4 Models with 4-cylinder engines Removal 1 Park the vehicle on a level surface and set the steering wheel in the straight ahead position. On models with a driver’s airbag, remove the ignition key and engage the steering column lock, to prevent rotation of the steering wheel. 2 Disconnect the battery negative cable and position it away from the terminal. 3 Apply the handbrake, select first gear (or Park, as applicable), then jack up the front of the vehicle and support it securely on axle stands. 4 Where applicable, remove the fixings and lower the undertray away from the engine bay. 5 Mark the position of the steering drop arm in relation to the steering gear arm. Unscrew the nut securing the steering drop arm to the bottom of the steering gear, then use a suitable puller to pull the arm from the splines on the sector shaft. 6 Working in the driver’s footwell, remove the securing clips/screws and detach the trim panel from the lower side of the facia. 7 Unscrew and remove the upper clamp bolt from the steering column flexible coupling; refer to Section 22. Slacken and remove the lower clamp bolt, that secures the flexible joint to the top of the steering gear. Prise the flexible joint apart, to release it from the steering gear, then slide it upwards onto the steering column as far as it will go. 8 Position a container beneath the steering gear to catch any spilt hydraulic fluid. 9 Identify the pressure and return lines for location then unscrew the union nuts and pull the lines from the steering gear. Plug the line 23.13a Depress the locking button . . . 23.13b . . . and withdraw the contact unit from the rear of the lock cylinder housing ends and steering gear ports to reduce leakage and to prevent the ingress of debris. 10 Unscrew the securing bolts and remove the metal heat shield from the steering gear casing. 11 Unscrew the mounting bolts and nuts and withdraw the steering gear via the underside of the vehicle. Recover any shims fitted and make a note of their locations to aid correct refitting. union nuts to the specified torque. 19 Refit the engine compartment undertray and tighten the screws securely. 20 Lower the vehicle to the ground, then reconnect the battery negative cable. 21 Check the fluid level in the power steering fluid reservoir. Top up if necessary and refit the cap. 22 With the engine idling, turn the steering from lock to lock several times in order to bleed trapped air from the system, then recheck and top-up the power steering fluid level. Refitting Note: If you are fitting a new steering gear assembly to a pre- 1996 vehicle, it will be necessary to fit a modified steering gear-tobulkhead rubber seal. 12 Where applicable (see Note above), slide the new rubber seal over the steering gear, such that the OBEN marking is aligned with the identification plate on the steering gear. 13 With the steering wheel centralised, lift the steering gear into position and insert each of the securing bolts, together with any shims recovered during removal. Tighten the bolts progressively to the specified torque, in a clockwise sequence, starting with the upper left hand bolt, as viewed from the right hand wheel arch. 14 Ensure that the steering wheel and road wheels are still in the straight ahead position, then reconnect the steering drop arm to the steering gear sector shaft and tighten the nut to the specified torque. On models equipped with a driver’s airbag, insert the ignition key to release the steering column lock and observe the alignment markings made during removal when reconnecting the drop arm to the steering gear. 15 Fit the heat shield to the steering gear casing, then insert and tighten the securing bolts to the specified torque. 16 Working inside the vehicle, slide the flexible coupling down the inner section of the steering column and engage it with the top of the steering gear. Insert the flexible coupling upper and lower clamp bolts and tighten them to the specified torque. 17 Refit the lower trim panel to the underside of the facia. 18 Fit new O-ring seals to the hydraulic pressure and return lines. Remove the plugs, then reconnect the pressure and return lines to the steering gear ports and tighten the 3510 Vauxhall/Opel Omega Models with 6- cylinder engines Removal 23 Park the vehicle on a level surface and set the steering wheel in the straight ahead position. 24 Disconnect the battery negative cable and position it away from the terminal. 25 Apply the handbrake, select first gear (or Park, as applicable), then jack up the front of the vehicle and support it securely on axle stands. 26 Remove the fixings and lower the undertray away from the engine bay. 27 Mark the position of the steering drop arm in relation to the steering gear arm. Unscrew the nut securing the steering drop arm to the bottom of the steering gear, then use a suitable puller to pull the arm from the splines on the sector shaft. 28 Unscrew the securing bolts and remove the metal heat shield from the steering gear casing. 29 Unplug the wiring harness from the steering gear transducer at the multiway connector. 30 Unbolt the engine movement damping strut from the right hand side of the engine, then remove the nut securing the right hand engine mounting block to the chassis bracket; see Chapter 2C, Section 17, for details. 31 On models with a driver’s airbag, remove the ignition key and engage the steering column lock, to prevent rotation of the steering wheel. 32 Disconnect the vacuum hose from the brake servo, with reference to Chapter 9, Section 15. 33 Depressurise the fuel system as described in Chapter 4A, then unscrew the union nuts and disconnect the fuel supply and return lines from the manifold. Suspension and steering 10•17 34 Unbolt the coolant reservoir from the bodywork and position it to one side, leaving the coolant hoses connected. 35 Disconnect the fuel vapour hoses from the charcoal canister ports, as described in Chapter 4B, Section 4. 36 Position a container beneath the steering gear to catch any spilt hydraulic fluid. 37 Identify the pressure and return lines for location then unscrew the union nuts and pull the lines from the steering gear (see illustration). Plug the line ends and steering gear ports to reduce leakage and to prevent the ingress of debris. 38 Working in the driver’s footwell, remove the securing clips/screws and detach the trim panel from the lower side of the facia. Remove the securing screws and detach the ventilation duct from the rear of the vent grille assembly and the side of the air distributor. 39 Unscrew and remove the upper clamp bolt from the steering column flexible coupling; refer to Section 22. Slacken and remove the lower clamp bolt, that secures the flexible joint to the top of the steering gear. Prise the flexible joint apart, to release it from the steering gear, then slide it upwards onto the steering column as far as it will go. 40 Attach an engine lifting hoist or beam to the engine lifting eyelets and raise the right hand side of the engine slightly - refer to the information given in Chapter 2C, Section 17. Raise the engine by about 3 cm to allow access to the steering gear. 41 Remove the starter motor as described in Chapter 5A. 42 Unscrew the mounting bolts and nuts and withdraw the steering gear via the underside of the vehicle (see illustration). Recover any shims fitted and make a note of their locations to aid correct refitting. Refitting Note: If you are fitting a new steering gear assembly to a pre- 1996 vehicle, it will be necessary to fit a modified steering gear-tobulkhead rubber seal. 43 Where applicable (see Note above), slide the new rubber seal over the steering gear, such that the OBEN marking is aligned with the identification plate on the steering gear. 44 With the steering wheel centralised, lift the steering gear into position and push the upper 24.37 Power steering gear fluid pressure and return lines (arrowed) 24.42 Steering gear mounting bolts viewed via right hand wheel arch shaft as far as possible into the flexible joint. Insert each of the steering gear securing bolts, together with any shims/spacers recovered during removal. Tighten the bolts progressively to the specified torque, in a clockwise sequence, starting with the upper left hand bolt, as viewed from the right hand wheel arch. 45 Reconnect the wiring to the steering gear transducer. 46 Refit the starter motor as described in Chapter 5A. 47 Working inside the vehicle, slide the flexible coupling down the inner section of the steering column and engage it with the top of the steering gear. Insert the flexible coupling upper and lower clamp bolts and tighten them to the specified torque. 48 Refit the ventilation duct, then refit the lower trim panel to the underside of the facia. 49 Lower the engine and remove the engine lifting equipment. Refit the engine mounting block securing nuts and the engine movement damper strut, as described in Chapter 2C, Section 17. 50 Reconnect the vacuum hose to the brake servo, with reference to Chapter 9, Section 15. 51 Refit the coolant reservoir to the bodywork and tighten the bolts securely. 52 Fit new O-ring seals to the hydraulic pressure and return lines. Remove the plugs, then reconnect the pressure and return lines to the steering gear ports and tighten the union nuts to the specified torque. 53 Reconnect the fuel supply and return lines to the manifold and tighten the union nuts to the specified torque. 54 Reconnect the fuel vapour hoses to the charcoal canister ports, with reference to Chapter 4B, Section 4. 55 Ensure that the steering wheel and road wheels are still in the straight ahead position, then reconnect the steering drop arm to the steering gear sector shaft and tighten the nut to the specified torque. Observe the alignment markings made during removal when reconnecting the drop arm to the steering gear. 56 Fit the heat shield to the steering gear casing, then insert and tighten the securing bolts to the specified torque. 57 Refit the engine compartment undertray and tighten the screws securely. 58 Lower the vehicle to the ground, then reconnect the battery negative cable. 59 Check the fluid level in the power steering fluid reservoir. Top up if necessary and refit the cap. 60 With the engine idling, turn the steering from lock to lock several times in order to bleed trapped air from the system, then recheck and top-up the power steering fluid level. 25 Steering tie-rods removal and refitting 3 Removal 1 Apply the handbrake, jack up the front of the vehicle and support it on axle stands. Remove the front wheels. 2 To remove a side tie-rod unscrew the nuts and use a proprietary balljoint removal tool to press out the ball-pins (see illustrations). 10 25.2a Unscrew the securing nut . . . 25.2b . . . and use a proprietary balljoint removal tool . . . 3510 Vauxhall/Opel Omega 25.2c . . . to separate the tie rod from the steering knuckle 10•18 Suspension and steering 25.5a Centre tie rod - engine and transmission removed for clarity 25.5b Centre tie-rod-to-idler balljoint nut (arrowed) If it is required to renew just one tie-rod end, disconnect the appropriate end only. 3 Loosen the clamp bolts and unscrew the tie-rod ends from the tie-rod tube, counting the exact number of turns required to remove them. 4 To remove the centre tie-rod, the side tie-rods must first be disconnected at their inner ends as described in paragraph 2. Note the fitted position of the centre tie-rod, to ensure correct refitting: the light-coloured rubber cover is nearest the idler arm, the darker-coloured rubber cover is nearest the steering arm. 5 Unscrew the nuts and disconnect the centre tie-rod from the drop arm and idler arm using the balljoint removal tool (see illustration). Refitting 6 Refitting is a reversal of removal; screw the tie-rod ends into the tie rod tube by the same number of turns counted during removal. Use new self-locking nuts and tighten all nuts and bolts to the specified torques (see illustration). On completion check and if necessary adjust the front wheel toe-in setting as described in Section 27. 26 Steering idler removal and refitting 3 Removal 1 Apply the handbrake, jack up the front of the vehicle and support on axle stands. Remove the left-hand wheel. 2 Disconnect the centre tie-rod by unscrewing the nut and using a balljoint removal tool to press out the ball-pin. 3 Unscrew the nut from the bottom of the idler bracket, and remove the heat shield followed by the idler arm. It is not possible to renew the bush separately from the arm. 4 If necessary, unbolt the idler bracket from the underbody. 27 Power steering pump removal and refitting on the temperature of the engine (see Weekly checks). Refit the cap on completion. Models with 6-cylinder engines Removal Models with 4-cylinder engines Removal 1 Remove the auxiliary drive belt as described in Chapter 1. 2 Position a container beneath the power steering pump, then unscrew the union nut and disconnect the pressure pipe. Loosen the clip and disconnect the supply hose - allow the excess hydraulic fluid to drain into the container. 3 Support the pump and remove the three mounting bolts. Withdraw the pump from the engine compartment. Refitting 4 Refit the power steering pump using a reversal of the removal procedure. Fit a new O-ring seal to the pump pressure pipe and tighten all unions, nuts and bolts to the specified torque wrench settings. 5 Refit the auxiliary drivebelt with reference to Chapter 1. 6 Pour fresh hydraulic fluid into the reservoir to the maximum level. Start the engine briefly, then switch off and top-up the fluid level. Do this several times until the level remains constant. With the engine idling, slowly turn the steering several times from lock to lock in order to purge air from the system. 7 With the engine stopped top up the fluid to the hot or cold level on the dipstick depending 8 On models with air conditioning, have the refrigerant circuit discharged by a Vauxhall dealer or an air-conditioning specialist. 9 Remove the auxiliary drivebelt with reference to Chapter 1. 10 Grip the power steering pump pulley with a strap wrench, then slacken and remove the pulley securing bolts. Separate the pulley from the pump shaft. 11 Position a container beneath the power steering pump, then unscrew the union nut and disconnect the pressure pipe. Loosen the clip and disconnect the supply hose - allow the excess hydraulic fluid to drain into the container. 12 Raise the front of the vehicle and rest it securely on axle stands. Remove the securing screws and detach the cover from the underside of the engine compartment. 13 Remove the screw and disconnect the earth cable from the power steering pump support mounting bracket. 14 Unbolt and remove the exhaust gas recirculation (EGR) valve bracing bar. Remove the securing screws and detach the support bracket from the underside of the power steering pump. 15 Unbolt the air conditioning refrigerant compressor from the power steering pump mounting bracket, with reference to Chapter 3, Section 12. 16 Slacken and withdraw the three bolts and withdraw the power steering pump mounting bracket from the engine, with the pump still attached. 17 Unbolt the power steering pump from its support bracket. Refitting Refitting 5 Refitting is a reversal of removal, but use new self-locking nuts, and tighten nuts and bolts to the specified torques. When fitting the idler bracket bolts apply a little locking compound to their threads. 3 25.5c Centre tie-rod-to-steering gear drop arm balljoint nut (arrowed) 25.6 Tighten all tie-rod nuts to the specified torques 3510 Vauxhall/Opel Omega 18 Refit the power steering pump using a reversal of the removal procedure. Fit a new O-ring seal to the pump pressure pipe and tighten all unions, nuts and bolts to the correct torque wrench settings, where specified. 19 Refit the auxiliary drivebelt with reference to Chapter 1. Suspension and steering 10•19 20 Have the air conditioning system recharged by a Vauxhall dealer, or an air conditioning specialist. 21 Pour fresh hydraulic fluid into the reservoir to the maximum level. Start the engine briefly, then switch off and top-up the fluid level. Do this several times until the level remains constant. With the engine idling, slowly turn the steering several times from lock to lock in order to purge air from the system. 22 With the engine stopped top up the fluid to the hot or cold level on the dipstick depending on the temperature of the engine (see Weekly checks). Refit the filler cap on completion. 28 Wheel alignment checking and adjustment 5 1 Accurate wheel alignment is essential for positive, accurate steering, stable road holding and to prevent abnormal tyre wear. Wheel alignment checking is carried out with the car loaded to its kerbside weight, and with the tyre pressures correctly adjusted. 2 The front toe setting, front camber angle, rear toe setting and rear camber angle are all adjustable, but can only be checked using specialised equipment; work of this nature should therefore be entrusted to a Vauxhall dealer or suitably-equipped tyre specialist. 10 3510 Vauxhall/Opel Omega 11•1 Chapter 11 Bodywork and fittings Contents Body exterior fittings - removal and refitting . . . . . . . . . . . . . . . . . . . 26 Bonnet and support struts - removal, refitting and adjustment . . . . 8 Bonnet lock spring - removal and refitting . . . . . . . . . . . . . . . . . . . . 10 Bonnet release cable - removal and refitting . . . . . . . . . . . . . . . . . . . 9 Bootlid - removal, refitting and adjustment . . . . . . . . . . . . . . . . . . . . 17 Bootlid lock components - removal and refitting . . . . . . . . . . . . . . . 18 Bumpers - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Central locking system components - removal and refitting . . . . . . . 21 Centre console - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 30 Door - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Door handles and lock components - removal and refitting . . . . . . . 13 Door inner trim panel - removal and refitting . . . . . . . . . . . . . . . . . . . 12 Door window regulator and glass - removal and refitting . . . . . . . . . 14 Electric window components - removal and refitting . . . . . . . . . . . . 22 Exterior mirrors and associated components - removal and refitting 23 Facia assembly - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . 32 Fuel filler flap lock and release cable - removal and refitting . . . . . . 16 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Glovebox - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Interior trim - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Lock and hinge lubrication . . . . . . . . . . . . . . . . . . . . . . . .see Chapter 1 Maintenance - bodywork and underframe . . . . . . . . . . . . . . . . . . . . 2 Maintenance - upholstery and carpets . . . . . . . . . . . . . . . . . . . . . . . 3 Major body damage - repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Minor body damage - repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Radiator grille - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 7 Rear quarter window glass (estate models) - removal and refitting . 15 Seat belt components - removal and refitting . . . . . . . . . . . . . . . . . . 28 Seats - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Sunroof components - removal and refitting . . . . . . . . . . . . . . . . . . . 25 Tailgate and support struts - removal, refitting and adjustment . . . . 19 Tailgate lock components - removal and refitting . . . . . . . . . . . . . . . 20 Windscreen and fixed window glass - general information . . . . . . . . 24 Degrees of difficulty Easy, suitable for novice with little experience 1 Fairly easy, suitable for beginner with some experience 2 Fairly difficult, suitable for competent DIY mechanic 3 Difficult, suitable for experienced DIY mechanic 4 Very difficult, suitable for expert DIY or professional 5 Specifications Torque wrench settings Driver’s airbag unit to steering wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . Front seat to floorpan* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Passenger airbag mounting bracket* . . . . . . . . . . . . . . . . . . . . . . . . . . . Passenger airbag unit to mounting bracket* . . . . . . . . . . . . . . . . . . . . . Seat belt anchor bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Seat belt height adjustment bracket . . . . . . . . . . . . . . . . . . . . . . . . . . . . Seat belt inertia reel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steering wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . * Use a new nut/bolt/screw 1 General information The bodyshell is of four-door Saloon, or five-door Estate configuration, and is made of high-strength low alloy sheet metal sections. The sections are alloy-galvanized on one or both sides, depending on their position on the vehicle. Most components are welded together, but some use is made of structural adhesives. The front wings are bolted on. The bonnet, doors and some other vulnerable panels are made of zinc-coated metal, and are further protected by being coated with an anti-chip primer prior to being sprayed. The front and rear doors incorporate safety bars as protection in the event of a side impact. Nm 8 20 20 8 35 20 35 20 lbf ft 6 15 15 6 26 15 26 15 Electrically operated front windows are fitted to all models. Electrically operated rear windows fitted as standard equipment on CD, CDX and Elite models and are optional on lower specification models. Extensive use is made of plastic materials, mainly in the interior, but also in exterior components. The front and rear bumpers and the front grille are injection-moulded from a synthetic material which is very strong, and yet light. Plastic components such as wheel arch liners are fitted to the underside of the vehicle, to improve the body’s resistance to corrosion. 2 Maintenance bodywork and underframe 1 The general condition of a vehicle’s bodywork is the one thing that significantly 3510 Vauxhall/Opel Omega affects its value. Maintenance is easy, but needs to be regular. Neglect, particularly after minor damage, can lead quickly to further deterioration and costly repair bills. It is important also to keep watch on those parts of the vehicle not immediately visible, for instance the underside, inside all the wheel arches, and the lower part of the engine compartment. The basic maintenance routine for the bodywork is washing - preferably with a lot of water, from a hose. This will remove all the loose solids which may have stuck to the vehicle. It is important to flush these off in such a way as to prevent grit from scratching the finish. The wheel arches and underframe need washing in the same way, to remove any accumulated mud which will retain moisture and tend to encourage rust. Paradoxically enough, the best time to clean the underframe and wheel arches is in wet weather, when the mud is thoroughly wet and soft. In very wet 11 11•2 Bodywork and fittings weather, the underframe is usually cleaned of large accumulations automatically, and this is a good time for inspection. Periodically, except on vehicles with a waxbased underbody protective coating, it is a good idea to have the whole of the underframe of the vehicle steam-cleaned, engine compartment included, so that a thorough inspection can be carried out to see what minor repairs and renovations are necessary. Steam-cleaning is available at many garages, and is necessary for the removal of the accumulation of oily grime, which sometimes is allowed to become thick in certain areas. If steam-cleaning facilities are not available, there are one or two excellent grease solvents available, which can be brush-applied; the dirt can then be simply hosed off. Note that these methods should not be used on vehicles with wax-based underbody protective coating, or the coating will be removed. Such vehicles should be inspected annually, preferably just prior to Winter, when the underbody should be washed down, and any damage to the wax coating repaired. Ideally, a completely fresh coat should be applied. It would also be worth considering the use of such wax-based protection for injection into door panels, sills, box sections, etc, as an additional safeguard against rust damage, where such protection is not provided by the vehicle manufacturer. After washing paintwork, wipe off with a chamois leather to give an unspotted clear finish. A coat of clear protective wax polish will give added protection against chemical pollutants in the air. If the paintwork sheen has dulled or oxidised, use a cleaner/polisher combination to restore the brilliance of the shine. This requires a little effort, but such dulling is usually caused because regular washing has been neglected. Care needs to be taken with metallic paintwork, as special nonabrasive cleaner/polisher is required to avoid damage to the finish. Always check that the door and ventilator opening drain holes and pipes are completely clear, so that water can be drained out. Brightwork should be treated in the same way as paintwork. Windscreens and windows can be kept clear of the smeary film which often appears, by the use of proprietary glass cleaner. Never use any form of wax or other body or chromium polish on glass. 3 Maintenance upholstery and carpets 1 Mats and carpets should be brushed or vacuum-cleaned regularly, to keep them free of grit. If they are badly stained, remove them from the vehicle for scrubbing or sponging, and make quite sure they are dry before refitting. Seats and interior trim panels can be kept clean by wiping with a damp cloth. If they do become stained (which can be more apparent on light-coloured upholstery), use a little liquid detergent and a soft nail brush to scour the grime out of the grain of the material. Do not forget to keep the headlining clean in the same way as the upholstery. When using liquid cleaners inside the vehicle, do not over-wet the surfaces being cleaned. Excessive damp could get into the seams and padded interior, causing stains, offensive odours or even rot. If the inside of the vehicle gets wet accidentally, it is worthwhile taking some trouble to dry it out properly, particularly where carpets are involved. Do not leave oil or electric heaters inside the vehicle for this purpose. 4 Minor body damage repair 2 Repairs of minor scratches in bodywork If the scratch is very superficial, and does not penetrate to the metal of the bodywork, repair is very simple. Lightly rub the area of the scratch with a paintwork renovator, or a very fine cutting paste, to remove loose paint from the scratch, and to clear the surrounding bodywork of wax polish. Rinse the area with clean water. Apply touch-up paint to the scratch using a fine paint brush; continue to apply fine layers of paint until the surface of the paint in the scratch is level with the surrounding paintwork. Allow the new paint at least two weeks to harden, then blend it into the surrounding paintwork by rubbing the scratch area with a paintwork renovator or a very fine cutting paste. Finally, apply wax polish. Where the scratch has penetrated right through to the metal of the bodywork, causing the metal to rust, a different repair technique is required. Remove any loose rust from the bottom of the scratch with a penknife, then apply rust-inhibiting paint, to prevent the formation of rust in the future. Using a rubber or nylon applicator, fill the scratch with bodystopper paste. If required, this paste can be mixed with cellulose thinners, to provide a very thin paste which is ideal for filling narrow scratches. Before the stopper-paste in the scratch hardens, wrap a piece of smooth cotton rag around the top of a finger. Dip the finger in cellulose thinners, and quickly sweep it across the surface of the stopper-paste in the scratch; this will ensure that the surface of the stopper-paste is slightly hollowed. The scratch can now be painted over as described earlier in this Section. Repairs of dents in bodywork When deep denting of the vehicle’s bodywork has taken place, the first task is to pull the dent out, until the affected bodywork almost attains its original shape. There is little point in trying to restore the original shape completely, as the metal in the damaged area will have stretched on impact, and cannot be reshaped fully to its original contour. It is better 3510 Vauxhall/Opel Omega to bring the level of the dent up to a point which is about 3 mm below the level of the surrounding bodywork. In cases where the dent is very shallow anyway, it is not worth trying to pull it out at all. If the underside of the dent is accessible, it can be hammered out gently from behind, using a mallet with a wooden or plastic head. Whilst doing this, hold a suitable block of wood firmly against the outside of the panel, to absorb the impact from the hammer blows and thus prevent a large area of the bodywork from being ‘belled-out’. Should the dent be in a section of the bodywork which has a double skin, or some other factor making it inaccessible from behind, a different technique is called for. Drill several small holes through the metal inside the area - particularly in the deeper section. Then screw long self-tapping screws into the holes, just sufficiently for them to gain a good purchase in the metal. Now the dent can be pulled out by pulling on the protruding heads of the screws with a pair of pliers. The next stage of the repair is the removal of the paint from the damaged area, and from an inch or so of the surrounding ‘sound’ bodywork. This is accomplished most easily by using a wire brush or abrasive pad on a power drill, although it can be done just as effectively by hand, using sheets of abrasive paper. To complete the preparation for filling, score the surface of the bare metal with a screwdriver or the tang of a file, or alternatively, drill small holes in the affected area. This will provide a really good ‘key’ for the filler paste. To complete the repair, see the Section on filling and respraying. Repairs of rust holes or gashes in bodywork Remove all paint from the affected area, and from an inch or so of the surrounding ‘sound’ bodywork, using an abrasive pad or a wire brush on a power drill. If these are not available, a few sheets of abrasive paper will do the job most effectively. With the paint removed, you will be able to judge the severity of the corrosion, and therefore decide whether to renew the whole panel (if this is possible) or to repair the affected area. New body panels are not as expensive as most people think, and it is often quicker and more satisfactory to fit a new panel than to attempt to repair large areas of corrosion. Remove all fittings from the affected area, except those which will act as a guide to the original shape of the damaged bodywork (eg headlamp shells etc). Then, using tin snips or a hacksaw blade, remove all loose metal and any other metal badly affected by corrosion. Hammer the edges of the hole inwards, in order to create a slight depression for the filler paste. Wire-brush the affected area to remove the powdery rust from the. surface of the remaining metal. Paint the affected area with rust-inhibiting paint; if the back of the rusted area is accessible, treat this also. Bodywork and fittings 11•3 Before filling can take place, it will be necessary to block the hole in some way. This can be achieved by the use of aluminium or plastic mesh, or aluminium tape. Aluminium or plastic mesh, or glass-fibre matting is probably the best material to use for a large hole. Cut a piece to the approximate size and shape of the hole to be filled, then position it in the hole so that its edges are below the level of the surrounding bodywork. It can be retained in position by several blobs of filler paste around its periphery. Aluminium tape should be used for small or very narrow holes. Pull a piece off the roll, trim it to the approximate size and shape required, then pull off the backing paper (if used) and stick the tape over the hole; it can be overlapped if the thickness of one piece is insufficient. Burnish down the edges of the tape with the handle of a screwdriver or similar, to ensure that the tape is securely attached to the metal underneath. Bodywork repairs filling and respraying Before using this Section, see the Sections on dent, deep scratch, rust holes and gash repairs. Many types of bodyfiller are available, but generally speaking, those proprietary kits which contain a tin of filler paste and a tube of resin hardener are best for this type of repair. A wide, flexible plastic or nylon applicator will be found invaluable for imparting a smooth and well-contoured finish to the surface of the filler. Mix up a little filler on a clean piece of card or board - measure the hardener carefully (follow the maker’s instructions on the pack), otherwise the filler will set too rapidly or too slowly. Using the applicator, apply the filler paste to the prepared area; draw the applicator across the surface of the filler to achieve the correct contour and to level the surface. As soon as a contour that approximates to the correct one is achieved, stop working the paste - if you carry on too long, the paste will become sticky and begin to ‘pick-up’ on the applicator. Continue to add thin layers of filler paste at 20minute intervals, until the level of the filler is just proud of the surrounding bodywork. Once the filler has hardened, the excess can be removed using a metal plane or file. From then on, progressively-finer grades of abrasive paper should be used, starting with a 40-grade production paper, and finishing with a 400-grade wet-and-dry paper. Always wrap the abrasive paper around a flat rubber, cork, or wooden block - otherwise the surface of the filler will not be completely flat. During the smoothing of the filler surface, the wet-anddry paper should be periodically rinsed in water. This will ensure that a very smooth finish is imparted to the filler at the final stage. At this stage, the ‘dent’ should be surrounded by a ring of bare metal, which in turn should be encircled by the finely ‘feathered’ edge of the good paintwork. Rinse the repair area with clean water, until all of the dust produced by the rubbing-down operation has gone. Spray the whole area with a light coat of this will show up any imperfections in the surface of the filler. Repair these imperfections with fresh filler paste or bodystopper, and once more smooth the surface with abrasive paper. If bodystopper is used, it can be mixed with cellulose thinners, to form a really thin paste which is ideal for filling small holes. Repeat this spray-and-repair procedure until you are satisfied that the surface of the filler, and the feathered edge of the paintwork, are perfect. Clean the repair area with clean water, and allow to dry fully. The repair area is now ready for final spraying. Paint spraying must be carried out in a warm, dry, windless and dust-free atmosphere. This condition can be created artificially if you have access to a large indoor working area, but if you are forced to work in the open, you will have to pick your day very carefully. If you are working indoors, dousing the floor in the work area with water will help to settle the dust which would otherwise be in the atmosphere. If the repair area is confined to one body panel, mask off the surrounding panels; this will help to minimise the effects of a slight mis-match in paint colours. Bodywork fittings (eg chrome strips, door handles etc) will also need to be masked off. Use genuine masking tape, and several thicknesses of newspaper, for the masking operations. Before commencing to spray, agitate the aerosol can thoroughly, then spray a test area (an old tin, or similar) until the technique is mastered. Cover the repair area with a thick coat of primer; the thickness should be built up using several thin layers of paint, rather than one thick one. Using 400 grade wet-and-dry paper, rub down the surface of the primer until it is really smooth. While doing this, the work area should be thoroughly doused with water, and the wetand-dry paper periodically rinsed in water. Allow to dry before spraying on more paint. Spray on the top coat, again building up the thickness by using several thin layers of paint. Start spraying in the centre of the repair area, and then, using a circular motion, work outwards until the whole repair area and about 2 inches of the surrounding original paintwork is covered. Remove all masking material 10 to 15 minutes after spraying on the final coat of paint. Allow the new paint at least two weeks to harden, then, using a paintwork renovator or a very fine cutting paste, blend the edges of the paint into the existing paintwork. Finally, apply wax polish. Plastic components With the use of more and more plastic body components by the vehicle manufacturers (eg bumpers. spoilers, and in some cases major body panels), rectification of more serious damage to such items has become a matter of either entrusting repair work to a specialist in this field, or renewing complete components. Repair 3510 Vauxhall/Opel Omega of such damage by the DIY owner is not really feasible, owing to the cost of the equipment and materials required for effecting such repairs. The basic technique involves making a groove along the line of the crack in the plastic, using a rotary burr in a power drill. The damaged part is then welded back together, using a hot air gun to heat up and fuse a plastic filler rod into the groove. Any excess plastic is then removed, and the area rubbed down to a smooth finish. It is important that a filler rod of the correct plastic is used, as body components can be made of a variety of different types (eg polycarbonate, ABS, polypropylene). Damage of a less serious nature (abrasions, minor cracks etc) can be repaired by the DIY owner using a two-part epoxy filler repair. Once mixed in equal, this is used in similar fashion to the bodywork filler used on metal panels. The filler is usually cured in twenty to thirty minutes, ready for sanding and painting. If the owner is renewing a complete component himself, or if he has repaired it with epoxy filler, he will be left with the problem of finding a suitable paint for finishing which is compatible with the type of plastic used. At one time, the use of a universal paint was not possible, owing to the complex range of plastics encountered in body component applications. Standard paints, generally speaking, will not bond to plastic or rubber satisfactorily, but suitable paints to match any plastic or rubber finish, can be obtained from dealers. However, it is now possible to obtain a plastic body parts finishing kit which consists of a pre-primer treatment, a primer and coloured top coat. Full instructions are normally supplied with a kit, but basically, the method of use is to first apply the pre-primer to the component concerned, and allow it to dry for up to 30 minutes. Then the primer is applied, and left to dry for about an hour before finally applying the special-coloured top coat. The result is a correctly-coloured component, where the paint will flex with the plastic or rubber, a property that standard paint does not normally possess. 5 Major body damage repair 5 Where serious damage has occurred, or large areas need renewal due to neglect, it means that complete new panels will need welding-in, and this is best left to professionals. If the damage is due to impact, it will also be necessary to check completely the alignment of the bodyshell, and this can only be carried out accurately by a Vauxhall/Opel dealer using special jigs. If the body is left misaligned, it is primarily dangerous, as the car will not handle properly, and secondly, uneven stresses will be imposed on the steering, suspension and possibly transmission, causing abnormal wear, or complete failure, particularly to such items as the tyres. 11 11•4 Bodywork and fittings 6 Bumpers removal and refitting 2 Front bumper Removal 1 Remove the radiator grille as described in Section 7. Remove the securing screws and detach the trim panels from the lower edge of each headlamp unit (see illustrations). 2 Remove the screws securing the lower edge of the front wheel arch liner in position, then unscrew and remove the two mounting screws from the trailing edge of the bumper moulding (see illustrations). 3 Remove the plastic rivets securing the lower edge of the front bumper to the front valance. To do this, depress the centre pins using a screwdriver, then prise out the rivet body (see illustrations). 4 Unscrew and remove the upper mounting bolts, located next to the headlamp units, then carefully withdraw the front bumper from the front of the vehicle (see illustrations). As the wiring becomes accessible, unplug the wiring from the foglamps and ambient air temperature sensor (where applicable). 5 If required, slacken and withdraw the securing bolts and then withdraw the bumper centre member from the front of the vehicle (see illustrations). 6.1a Remove the securing screws . . . 6.1b . . . and detach the trim panels from the lower edge of each headlamp unit 6.2a Unscrew and remove the upper . . . 6.2b . . . and lower mounting screws from the trailing edge of the bumper moulding 6.3a Depress the centre pins using a screwdriver . . . 6.3b . . . then remove the plastic rivets securing the lower edge of the front bumper to the front valance 6.4a Unscrew and remove the upper mounting bolts . . . 6.4b . . . then carefully withdraw the front bumper from the front of the vehicle 6.5a Slacken and withdraw the securing bolts . . . 6.5b . . . and then withdraw the bumper centre member from the front of the vehicle 3510 Vauxhall/Opel Omega Bodywork and fittings 11•5 6.7 Unscrew the bolts securing the upper and lower leading edge of the bumper moulding to the bodywork 6.8 Remove the screws and withdraw the boot striker trim panel 6.9a Depress the centre pins using a screwdriver . . . bolts (three each side) securing the upper and lower leading edge of the bumper moulding to the bodywork (see illustration). 8 Open the bootlid, then remove the screws and withdraw the boot striker trim panel (see illustration). 9 Remove the plastic rivets securing the lower edge of the bumper to the rear valance. To do this, depress the centre pins using a screwdriver, then prise out the rivet body (see illustrations). 10 Prise off the protective caps, then unscrew the four screws securing the upper edge of the bumper moulding to the bodywork (see illustration). 11 Carefully withdraw the rear bumper from the rear of the vehicle, disconnecting the number plate lamp unit wiring as it becomes accessible (see illustration). 12 To remove the rear bumper centre member, slacken and withdraw the securing nuts, then detach the centre member from its mounting bracket (see illustrations). 6.9b . . . then prise out the plastic rivets securing the lower edge of the bumper to the rear valance 6.10 Prise off the protective caps and remove the screws securing the upper edge of the bumper moulding to the bodywork 6.11 Carefully withdraw the rear bumper from the vehicle 6.12a Slacken and withdraw the securing nuts . . . 6.12b . . . then detach the centre member from its mounting bracket 6.14 Remove the securing screws and detach the lower edges of the plastic liners from both rear wheel arches Refitting 6 Refitting is a reversal of removal, noting the following points. a) Tighten all fixings to the correct torque, where specified. b) When refitting the headlamp trim panels, ensure that the locating lugs engage which their corresponding recesses. c) Ensure that the ambient temperature sensor wiring is securely reconnected, where applicable. Rear bumper Saloon models Removal 7 At the rear of each wheel arch, unscrew the Refitting 13 Refitting is a reversal of removal but tighten all fixings to the correct torque, where specified. Rear bumper Estate models Removal 14 Remove the securing screws and detach the lower edges of the plastic liners from both rear wheel arches (see illustration). 11 3510 Vauxhall/Opel Omega 11•6 Bodywork and fittings 6.15 Unscrew the securing bolts and remove the reflectors from the underside of each rear light unit 6.16 unscrew the bolts securing the leading edge of the bumper moulding to the bodywork 6.17a Depress the centre pins using a screwdriver . . . 6.17b . . . then prise out the plastic rivets securing the lower edge of the bumper to the rear valance 6.18a Prise off the protective caps . . . 6.18b . . . then unscrew the screws securing the upper edge of the bumper moulding to the bodywork 15 Unscrew the securing bolts and remove the reflectors from the underside of each rear light unit (see illustration). 16 At the rear of each wheel arch, unscrew the bolts (one each side) securing the leading edge of the bumper moulding to the bodywork (see illustration). 17 Remove the plastic rivets securing the lower edge of the bumper to the rear valance. To do this, depress the centre pins using a screwdriver, then prise out the rivet body (see illustrations). 18 Prise off the protective caps, then unscrew the six screws securing the upper edge of the bumper moulding to the bodywork (see illustrations). 19 Carefully withdraw the rear bumper from the rear of the vehicle (see illustration). To remove the rear bumper centre member, slacken and withdraw the four securing bolts, then detach the centre member from its mounting bracket. 6.19 Carefully withdraw the rear bumper from the rear of the vehicle 7.1 Slacken and withdraw the radiator grille upper mounting screws 7.2a Depress the locking catch . . . 3510 Vauxhall/Opel Omega Refitting 20 Refitting is a reversal of removal but tighten all fixings to the correct torque, where specified. 7 Radiator grille removal and refitting 1 Removal 1 Open the bonnet, then slacken and withdraw the radiator grille upper mounting screws (see illustration). 2 Depress the locking catch, then lift the radiator grille from the front bumper (see illustrations). 7.2b . . . then lift the radiator grille from the front bumper Bodywork and fittings 11•7 Refitting Support struts 3 Refitting is a reversal of removal, ensuring that the lugs on the lower edge of the grille engage correctly with the corresponding recesses in the upper edge of the bumper. Removal 8 Bonnet and support struts removal, refitting and adjustment 2 10 Bonnet lock spring removal and refitting 12 Open the bonnet, and have an assistant support it. 13 Using a screwdriver prise out the retaining spring clips and disconnect the upper end of the strut from the balljoints on the bonnet. 14 Unscrew the securing bolts and detach the lower end of the strut from the bodywork. Note which way round the strut is fitted. Refitting Bonnet 15 Refitting is a reversal of removal. Removal 1 Open the bonnet, and have an assistant support it. Disconnect the support struts from the bonnet balljoints, as described in the next sub-Section. 2 Using a marker pen or paint, mark around the hinge positions on the bonnet. 3 Disconnect the windscreen washer fluid hose at the connector and support. Unplug the wiring harness at the connector. 4 With the aid of the assistant, unscrew the bolts securing the bonnet to the hinges on both sides. 5 Lift off the bonnet taking care not to damage the vehicle paintwork. Refitting 6 With the aid of the assistant, align the marks made on the bonnet before removal with the hinges, then refit and tighten the bonnet securing bolts. 7 Reconnect the windscreen washer fluid hose and wiring harness. 8 Refit the support struts to the bonnet as described in the next sub-Section, then check the bonnet adjustment as follows. Adjustment 9 Lower the bonnet slowly to its closed position, ensuring that misalignment does not cause the edges of the bonnet to strike the wings. Check that there is an equal gap between the sides of the bonnet and the wing panels, and between the front of the bonnet and the upper edges of the headlamp units. Check also that the bonnet sits flush in relation to the surrounding body panels. 10 The bonnet should close smoothly and positively without excessive pressure. If this is not the case, adjustment will be required. 11 To adjust the bonnet alignment, loosen the bonnet mounting bolts, and move the bonnet on the bolts as required (the bolt holes in the hinges are elongated to allow adjustment). To adjust the bonnet front height in relation to the front wings, adjustable rubber bump stops are fitted to the front corners of the bonnet. These may be screwed in or out as necessary. After making an adjustment, the bonnet striker must be adjusted so that the lock spring holds the bonnet firmly against the rubber bump stops. Loosen the locknut and screw the striker in or out as necessary. 9 Bonnet release cable removal and refitting 3 Removal 1 Remove the lower trim panel from under the driver’s side of the facia. Undo the screws and remove the plastic panel to the right of the drivers footwell, to expose the release cable handle mountings. 2 Open the bonnet and remove the radiator grille as described in Section 7. Release the securing clips, undo the screws and remove the cover panel from above the radiator. 3 Disconnect the front end of the release cable from the bonnet lock spring, by reaching between the radiator and the bodywork. On models with air conditioning, it will be necessary to remove the left hand auxiliary cooling fan (see Chapter 3) from the condenser to allow access to the underside of the bonnet lock. 4 Unbolt the release lever and its mounting bracket from the bodywork at the right of the driver’s footwell. Note that the release handle and cable are only available as a complete assembly. 5 Release the cable from the support clips in the engine compartment, then withdraw the cable through the rubber grommet and withdraw into the engine compartment. Note that the cable runs from the bonnet lock around the left hand side of the engine compartment behind the main fusebox, then along the bulkhead to the right hand side of the engine compartment before passing through the bulkhead and entering the passenger compartment. As an aid to refitting, tie a length of string to the cable before removing it and leave the string in position ready for refitting. 2 Removal 1 The bonnet is held in its locked position by means of a strong coil spring and a pin, which engages with the striker plate on the front edge of the bonnet. The release cable is connected to the striker plate catch, which is held in the locked position by a spring. 2 The pin and its coil spring may be removed from the bonnet by unscrewing it from the locknut, however measure its fitted length first as a guide to refitting it. 3 To remove the striker plate spring, first remove the radiator grille (see Section 7) then disconnect the bonnet release cable and unhook the spring from the front crossmember. Refitting 4 Refitting is a reversal of removal. 11 Door removal and refitting 3 Front door Removal 1 The door hinges are welded onto the door frame and the body pillar. Where necessary, adjustment is carried out using special tools to bend the hinges. 2 Open the door to gain access to the wiring connector, which is fixed to the front inside edge of the door. Disconnect the wiring connector from the front edge of the door. To do this, unscrew the connector locking ring, then pull the connector away from the door (see illustration). 3 Unscrew and remove the bolt securing the door check link to the vehicle body (see illustration). Refitting 6 Refitting is a reversal of removal, but tie the string to the release lever end of the cable, and use the string to pull the cable into position. Ensure that the cable is routed as noted before removal, and make sure that the grommet is correctly seated. 3510 Vauxhall/Opel Omega 11 11.2 Location of the front door wiring connector (arrowed) 11•8 Bodywork and fittings lifting the door on its hinges. After adjustment, make sure that the door lock engages correctly with the striker on the body pillar. If necessary loosen the striker retaining screws using a Torx key, then reposition the striker and tighten the screws. Rear door 11.3 Unscrew and remove the bolt (arrowed) securing the door check link to the vehicle body 4 Remove the plastic covers from the door hinge pins (see illustration). Have an assistant support the door, then drive both hinge pins out of position using a hammer and suitable punch. Note: Vauxhall/Opel technicians use a special hinge pin removal tool which acts like a slide hammer. Remove the door from the vehicle. 5 Inspect the hinge pins for signs of wear or damage, and renew if necessary. 7 The removal and refitting procedure is the same as that described for the front door, except that the wiring harness is located behind a rubber grommet at the base of the B-pillar. To gain access to it, open the front and rear door, prise the grommet from the bodywork and withdraw the connector from the B-pillar. 12 Door inner trim panel removal and refitting 2 Front door Removal 6 Refitting is a reversal of removal, but check that when shut the door is positioned centrally within the body aperture. If the hinge pins have been renewed and adjustment is still required, the hinges will have to be re-aligned using special tools. This work must be carried out by a Vauxhall/Opel dealer, however minor adjustment may be possible by physically 1 Disconnect the battery negative (earth) lead (see Chapter 5A). 2 On models with manually-adjustable door mirrors, carefully pull off the mirror adjustment handle, then prise off the triangular plastic cover taking care not to damage the retaining clips. Remove the foam padding. On models with electrically adjustable door mirrors, carefully prise off the triangular plastic cover panel, remove the foam padding and unplug the wiring from the tweeter unit (see Section 23 12.3 Prise the plastic cover from the inside of the interior door handle 12.4 Carefully prise the grip from the underside of the door pull handle 12.5b . . . undo the screws . . . 12.5c . . . and remove the door pull handle Refitting 3510 Vauxhall/Opel Omega 11.4 Remove the plastic covers from the door hinge pins for details). 3 Prise the plastic cover from the inside of the interior door handle (see illustration). 4 Carefully prise the grip from the underside of the door pull handle (see illustration). 5 Prise off the small plastic covers to expose the heads of the door handle surround securing screws. Undo the screws and remove the door pull handle. (see illustrations). 6 On base models, remove the window regulator handle by first closing the window and noting the fitted angle of the handle. Using a piece of cloth rag inserted behind the handle, release the clip then withdraw the handle from the splined shaft. 7 Prise the clip from the door locking knob, then detach the knob from the locking rod. Undo the screw and remove the locking knob trim panel (see illustrations). 12.5a Prise off the small plastic covers . . . 12.7a Prise the clip from the door locking knob and then detach the knob from the locking rod Bodywork and fittings 11•9 12.7b Undo the screw . . . 12.7c . . . and remove the locking knob trim panel 12.8a Prise off the protective caps . . . 12.8b . . . then remove the screws from the lower and front edges of the trim panel 12.9 Remove the trim panel from the door 12.10 If necessary, carefully peel the protective plastic membrane from the door 8 Prise off the protective caps (where applicable) then unscrew and remove the screws from the lower and front edges of the trim panel (see illustrations). 9 Use a wide-bladed screwdriver or trim removal tool to carefully prise the panel clips from the door. Unhook the top of the panel and remove it from the door (see illustration). 10 If necessary, carefully peel the protective plastic membrane from the door (see illustration). Note that it will necessary to cut around some of the panel securing clips to release the membrane from the door. Warning: On later models where the Supplementary Restraint System (SRS) includes side airbags, the door side impact sensors are air pressure sensitive and will only operate correctly if the protective plastic door membrane is refitted correctly; bear this in mind when removing the membrane from the door. See Chapter 12 for more information on the Supplementary Restraint System. lead (see Chapter 5A). 13 Use a small screwdriver to carefully prise off the ashtray unit from the armrest (see illustration). 14 Unclip the trim panel from behind the door lock release handle (see illustration). 15 Carefully prise the grip from the underside off the door pull handle (see illustration). 16 Prise the clip from the door locking knob, then detach the knob from the locking rod. Undo the screw and remove the locking knob trim panel (see illustrations). 17 Unscrew and remove the door pull handle retaining screws and then remove the pull handle from the door. Where applicable, unplug the window switch wiring connector as it becomes accessible (see illustrations). On models with rear door window demister fans, it will be necessary to lift the door pull handle assembly upwards, to detach it from the air ducting. 12.11 On models fitted with side airbags, it is important that the sealing strip around the edge of the membrane adheres to the door without gaps, to form an airtight seal Refitting 11 Refitting is a reversal of removal. On models fitted with side airbags, ensure that the plastic door membrane is securely refitted (see illustration). The sealing strip around the edge of the membrane must adhere to the door without gaps, to form an airtight seal. If the membrane was cut or torn during its removal, ensure that the loose edges are stuck to the door using a suitable adhesive/sealant. If you are in doubt about the integrity of the seal, it’s best to renew the membrane and sealing strip entirely. Rear door Removal 12 Disconnect the battery negative (earth) 11 12.13 Use a small screwdriver to carefully prise off the ashtray unit from the armrest 3510 Vauxhall/Opel Omega 12.14 Unclip the trim panel from behind the door lock release handle 11•10 Bodywork and fittings 12.15 Carefully prise the grip from the underside of the door pull handle 12.16a Prise the clip from the door locking knob . . 12.16b . . . then detach the knob from the locking rod 12.16c Undo the screw . . . 12.16d . . . and remove the locking knob trim panel 12.17a Unscrew and remove the door pull handle retaining screws . . . 18 Where a manual window regulator is fitted, fully close the window and note the position of the regulator handle. The handle must now be removed from the splined shaft. To do this, locate a cloth rag between the handle and the trim panel and pull it to one side to release the spring clip. The handle can now be removed from the splined shaft and the escutcheon removed. 19 Prise the kerb lamp unit from the door trim panel and disconnect the wiring from it (see Chapter 12, Section 6). 20 Unscrew and remove the screws from the rear and lower edges of the trim panel, then use a wide-bladed screwdriver or removal tool 12.17b . . . and then remove the pull handle from the door 12.17c Where applicable, unplug the window switch wiring connector 12.20a Unscrew and remove the screws from the rear and lower edges of the trim panel . . . 12.20b . . . lift the panel upwards to disengage it from the door, then remove it from the vehicle 12.20c Unplug the speaker wiring as it becomes accessible 12.21 If necessary, carefully peel the protective plastic membrane from the door 3510 Vauxhall/Opel Omega Bodywork and fittings 11•11 13.2 Press the interior handle forwards to release it from the elongated slots in the door panel 13.3 Twist the handle anticlockwise to unhook it from the link rod 13.7 Unscrew the nuts (arrowed) from the rear of the exterior handle 13.9a Release the plastic clip . . . 13.9b . . . detach the door lock mechanism link rod . . . to carefully prise the inner trim panel clips from the inside of the rear door. Lift the panel upwards to disengage it from the door, then unplug the speaker wiring as it becomes accessible. Remove the trim panel from the vehicle (see illustrations). 21 If necessary, carefully peel the protective plastic membrane from the door (see illustration). Note that it will necessary to cut around some of the panel securing clips to release the membrane from the door. Refitting 22 Refitting is a reversal of removal. Front door exterior handle 13 Door handles and lock components removal and refitting 3 Door interior handle Removal 1 Remove the door inner trim panel and peel back the protective plastic membrane as described in Section 12. 2 Press the interior handle forwards to release it from the elongated slots in the door panel (see illustration). 3 Twist the handle anticlockwise to unhook it from the link rod (see illustration). Refitting 4 Refitting is a reversal of removal. Removal 5 Remove the door inner trim panel, and peel back the protective plastic membrane as described in Section 12. 6 On models fitted with side air bags, remove the door side impact sensor together with its mounting bracket; refer to Section 24 of Chapter 12. 7 Unscrew the nuts from the rear of the exterior handle using a socket inserted through the aperture provided (see illustration). 8 Carefully withdraw the exterior handle from the door taking care not to damage the paintwork. Unplug the wiring connector, where applicable - cable tie the wire to the handle aperture, to prevent it dropping down inside the door. 9 Release the plastic clip, detach the door lock mechanism link rod and withdraw the handle from the door through handle aperture (see illustrations). Refitting 10 Refitting is a reversal of removal, but before refitting the inner trim panel, screw down the knurled nut on the handle linkage until it is free of play. Rear door exterior handle Removal 11 Remove the door inner trim panel, and peel back the protective plastic membrane as described in Section 12. 12 Undo the securing screw and remove the plastic security panel from the door lock mechanism (see illustrations). 11 13.9c . . . and withdraw the handle from the door through handle aperture 13.12a Undo the securing screw . . . 3510 Vauxhall/Opel Omega 13.12b . . . and remove the plastic security panel from the door lock mechanism 11•12 Bodywork and fittings 13.13a Unscrew the nuts, using a socket inserted through the aperture provided . . . 13.13b . . . and remove the mounting plate from the rear of the exterior door handle 13.14 Disconnect the link rod from the door handle by prising open the plastic clip 13 Unscrew the nuts, using a socket inserted through the aperture provided, and remove the mounting plate from the rear of the exterior door handle (see illustrations). 14 Disconnect the handle link rod from the door lock by prising open the plastic clips (see illustration). 15 Withdraw the handle from the door taking care not to damage the paintwork (see illustration). 22 Note the orientation of the cylinder housing, then drive out the roll pin using a suitable punch, and rotate the cylinder housing to release it from the exterior handle assembly. 23 Withdraw the lock cylinder from the handle assembly. and splay out the end roll pin using the punch, to ensure that the pin cannot fall out (see illustration). Refitting Refitting 24 Refitting is a reversal of removal. After securing the cylinder housing in position with a new roll pin, turn the handle assembly over Front door lock Removal 25 Remove the door inner trim panel, and peel back the protective plastic membrane as described in Section 12. 26 On models fitted with side air bags, remove the door side impact sensor together 16 Refitting is a reversal of removal, but before refitting the inner trim panel, screw down the knurled nut on the handle link rod until it is free of play. Front door lock cylinder models with conventional lock cylinder Removal 17 Remove the exterior handle as described previously in this Section. 18 Insert the key in the lock cylinder and turn it to the right. 19 Prise off the circlip and remove the cylinder from the rear of the handle assembly. Refitting 20 Refitting is a reversal of removal. Front door lock cylinder models with freewheeling lock cylinder Removal 21 Remove the exterior handle assembly as described previously in this Section. 13.24 Exploded view of front door lock cylinder assembly models with free-wheeling locks 13.15 Withdraw the handle from the door 1 Roll pin 2 Housing 3 Lock cylinder 4 Channel sleeve 5 Ball 6 Clutch 3510 Vauxhall/Opel Omega 7 Bracket 8 Washer 9 Carrier and lever 10 Torsion spring 11 Pressure spring Bodywork and fittings 11•13 13.29 Disconnecting the inner door handle link rod 13.30 Unscrew and remove the front door lock retaining screws 13.35 Disconnect the central locking wiring at the connector 13.36a Unscrew the lock mechanism mounting screws (arrowed) . . . with its mounting bracket; refer to Section 24 of Chapter 12. 27 Remove the exterior door handle as described previously in this Section. 28 Where fitted, disconnect the central locking wiring from the lock by levering up the plastic retainer and separating the connector. 29 Disconnect the link rods arms for the outer door handle, lock cylinder (where applicable) and inner door handle from the lock (see illustration). 30 At the rear edge of the door, undo the three retaining screws then withdraw the lock from inside the door while guiding the locking knob link rod through the hole provided (see illustration). through the exterior handle door aperture (see illustrations). Refitting 31 Refitting is a reversal of removal. 13.34 Disconnect the locking knob and interior handle link rods from the lock by releasing the plastic clips 13.36b . . . and withdraw the lock mechanism through the exterior handle door aperture 1 Operate the window so that it is about three quarters open. Disconnect the battery negative cable and position it away from the terminal. 2 Remove the door inner trim panel, and peel back the protective plastic membrane as described in Section 12. 3 If working on a rear door, remove the interior door handle, as described in Section 13. 4 On models fitted with side air bags, remove the door side impact sensor together with its mounting bracket; refer to Section 24 of Chapter 12. 5 On models with electric window regulators, unplug the winder motor wiring connector, by squeezing the retaining tags (see illustration). 6 Mark the position of the regulator guide rail mounting bolts in their in the elongated slots, then unscrew and remove the bolts (see illustration). 7 Have an assistant hold the window glass in position, then drill out the rivets securing the 14.5 On models with electric windows, unplug the winder motor wiring at the connector 14.6 Mark the position of the regulator guide rail mounting bolts then unscrew and remove the bolts Refitting 37 Refitting is a reversal of removal. 14 Door window regulator and glass removal and refitting 3 Window regulator Note: New rivets will be required to secure the regulator mechanism to the door on refitting. Removal Rear door lock Removal 32 Remove the door inner trim panel, and peel back the protective plastic membrane as described in Section 12. 33 Remove the rear door exterior handle as described previously in this Section. 34 Disconnect the locking knob and interior handle link rods from the lock by releasing the plastic clips (see illustration). 35 Disconnect the central locking wiring by levering up the plastic retainer and separating the connector (see illustration). 36 Unscrew the lock mechanism mounting screws and withdraw the lock mechanism 11 3510 Vauxhall/Opel Omega 11•14 Bodywork and fittings 14.7a Drill out the rivets securing the regulator to the door (arrowed - front door shown) 14.7b Slide the arm extensions from the channels at the bottom of the glass 14.8 Manoeuvre the regulator mechanism out through the aperture in the door regulator to the door; there are four rivets on the front door, six on rear doors with manual actuation and five on rear doors with electric actuation. Slide the arm extensions from the channels at the bottom of the glass (see illustrations). 8 Manoeuvre the regulator mechanism out through the aperture in the door (see illustration). bolts and check that the window opens and closes correctly. Finally refit the plastic membrane and inner trim panel. 10 After reconnecting the battery on models with electric window regulators the winder mechanism control electronics must be reprogrammed as follows: fully close the window then keep the switch held down for a further 5 seconds. Refitting Window glass front door sash window speaker from the door. 14 Remove the sealing strips from the inside and outside of the lower edge of the door window aperture (see illustration). 15 Peel the weather strip from the front edge of the door window aperture (see illustration). 16 Remove the rubber seal from the window guide channel (see illustration). 17 Slacken the window guide channel upper and lower securing bolts (see illustrations). 18 Slide the window glass to the top of the door, then tilt its upper corner forward to disengage it from the door and remove it (see illustration). 9 Refitting is a reversal of removal but use a pop-rivet gun to secure the regulator with new pop rivets (see illustration). Before refitting the inner trim panel and protective plastic membrane, adjust the position of the regulator by inserting the guide rail mounting bolts hand-tight, then raising and lowering the window fully. Tighten the guide rail mounting Removal 11 Remove the regulator as previously described in this Section. 12 Remove the exterior door mirror, as described in Section 23. 13 Undo the securing screws and remove the Refitting 19 Refitting is a reversal of removal. Ensure that the leading edge of the window glass engages with the guide channel, and that the 14.9 Use a pop-rivet gun to secure the regulator with new pop rivets 14.14 Remove the sealing strips from the inside and outside of the lower edge of the door window aperture 14.15 Peel the weather strip from the front edge of the door window aperture 14.16 Remove the rubber seal from the window guide channel 14.17a Slacken the window guide channel upper . . . 14.17b . . . and lower securing bolts 3510 Vauxhall/Opel Omega Bodywork and fittings 11•15 14.18 Tilt the window glass upper corner forward to disengage it, then remove it from the door 14.19a Ensure that the channel (arrowed) at the trailing edge of the glass engages with the rear edge of the door 14.19b Ensure that the leading edge of the window glass engages with the guide channel (arrowed) channel at the trailing edge of the glass engages with the rear edge of the door (see illustrations). 20 To adjust the height of the window glass in the closed position, slacken the window glass stop bolt (see illustration) then wind the window up until its upper edge is flush with the door weather strip. Tighten the window glass stop bolt. bolts (four bolts in total), then withdraw the guide channel from the door (see illustration). 25 Slide the window glass to the top of the door, then tilt its upper corner forward to disengage it from the door and remove it (see illustration). Window glass rear door sash window Refitting 21 Remove the regulator as previously described in this Section. 22 Remove the sealing strips from the inside and outside of the lower edge of the door window aperture (see illustrations). 23 Peel the weather strip from the rear edge of the door window aperture (see illustration). 24 Slacken and remove the window guide channel upper, centre and lower securing 26 Refitting is a reversal of removal. Ensure that the trailing edge of the window glass engages with the guide channel, and that the channel at the leading edge of the glass engages with the front edge of the door (see illustrations). 27 To adjust the height of the window glass in the closed position, slacken the window glass front and rear stop bolts then wind the window up until its upper edge is flush with the door weather strip (see illustrations). Tighten the window glass stop bolts. 14.22a Remove the sealing strips from the inside . . . 14.22b . . . and outside of the lower edge of the door window aperture 14.23 Peel the weather strip from the rear edge of the door window aperture 14.24a Slacken and remove the window guide channel upper . . . 14.24b . . . centre and lower securing bolts (arrowed), then withdraw the guide channel from the door 14.25 Slide the window glass to the top of the door, then tilt its upper corner forward to disengage it from the door and remove it Removal 14.20 Location of front door sash window stop bolt 11 3510 Vauxhall/Opel Omega 11•16 Bodywork and fittings 14.26a Ensure that the trailing edge of the window glass engages with the guide channel (arrowed) . . . 14.26b . . . and that the channel (arrowed) at the leading edge of the glass engages with the front edge of the door 14.27a Slacken the window glass front . . . 14.27b . . . and rear stop bolts 14.29a Carefully prise the rubber seal away from the window aperture . . . 14.29b . . . then slide the glass towards the front of the door and remove it Window glass rear door fixed quarter window Removal 28 Remove the rear door sash window as described previously in this Section. 29 Carefully prise the rubber seal away from the window aperture, then slide the glass towards the front of the door and remove it (see illustrations). Refitting 30 Refitting is a reversal of removal. Ensure that the rubber seal is pressed firmly into the window aperture. 15 Rear quarter window glass (estate models) removal and refitting 2 trim panels from the C-pillar. Remove the Band D-pillar trim panels in a similar manner. 5 Unscrew the nuts (13 in total) and remove the window glass from the body. Where applicable, unplug the wiring from the alarm system glass break sensor. Removal Refitting 3 Refitting is a reversal of removal but use suitable adhesive to stick the new rubber seal to the edge of the fuel filler flap. Note that a new flap must be painted with the body colour before fitting. 6 Refitting is a reversal of removal. Ensure that the rear passenger seat belt upper anchor bracket bolt is tightened to the specified torque wrench setting. 16 Fuel filler flap lock and release cable removal and refitting 2 Note: Refer to Section 21 for details of fuel filler flap locking servo removal and refitting. 1 Open the fuel flap and remove the filler cap. 2 Undo the two screws and withdraw the fuel filler flap. Refitting 17 Bootlid and support struts removal, refitting and adjustment 3 Bootlid Removal 1 Open the bootlid, then disconnect the wiring harness at the connector. 2 Using a pencil or marker pen, mark around the hinges on the bootlid as a guide for refitting. 3 With the aid of an assistant, unscrew the nuts that secure boot lid to the hinges, then lift off the boot lid (see illustration). 4 The hinges can be removed if required by unhooking the return springs and unbolting the hinges from the body. Removal 1 Unclip and remove the load space cover panel, then slacken and remove the screws and detach the relevant cover panel slider housing bodywork. 2 Unclip the cover panel and unbolt the rear seat belt upper anchor bracket from the Cpillar. 3 Unbolt and remove the rear passenger grab handle. 4 Prise out the plastic caps, then remove the C-pillar upper and lower trim panel securing screws. Release the clips using a blunt flat bladed tool and detach the upper and lower Refitting and adjustment 17.3 Unscrew the nuts (arrowed) that secure boot lid to the hinges 3510 Vauxhall/Opel Omega 5 Refitting is a reversal of removal, but make sure that the hinges are positioned as noted Bodywork and fittings 11•17 on removal and tighten the mounting bolts securely. With the bootlid closed, check that it is positioned centrally within the body aperture. If adjustment is necessary, turn the adjusting bolts and rubber buffers to reposition the bootlid. Check that the striker enters the lock centrally, and if necessary adjust the striker position by loosening the mounting bolt. Tighten the bolt on completion. the lock from inside the bootlid. Remove the lock handle and gasket from the outside of the bootlid (see illustrations). Refitting 4 Refitting is a reversal of removal. Check that when closed the bootlid lock engages the lock striker centrally. If necessary loosen the bolt and adjust the position of the striker, then tighten the bolt. Support struts Lock mechanism Removal 6 Open the boot lid and note which way round the struts are fitted. Have an assistant support the boot lid in its open position. 7 Using a small screwdriver, prise the spring clip from the top of the strut and disconnect it from the ball on the tailgate (see illustration). 8 Unbolt the bottom of the strut from the bodywork and remove it from the vehicle. Removal 17.7 Using a small screwdriver, prise the spring clip from the top of the strut Refitting 9 Refitting is a reversal of removal. 18 Bootlid lock components removal and refitting 2 5 Open the bootlid and remove the trim panel, as described in the previous subsection. 6 Disconnect the lock cylinder and handle assembly link rods by prising up their plastic retainers. 7 Unscrew the securing screws, then remove the lock mechanism from the bootlid (see illustration). Refitting Lock cylinder and handle assembly Removal 18.1a Prise carefully using a forked tool to release the press-stud fixings . . . 1 Open the bootlid and remove the trim panel by prising carefully using a forked tool to release the press-stud fixings (see illustrations). 2 Disconnect the lock link rods from the rear of the lock assembly by prising up the plastic retainer (see illustration). 3 Unscrew the mounting nuts, then withdraw 18.1b . . . and remove the trim panel from the inside of the bootlid 18.2 Disconnect the lock link rods from the rear of the lock assembly 8 Refitting is a reversal of removal. 19 Tailgate and support struts removal, refitting and adjustment 3 Tailgate Removal 1 Disconnect the battery negative (earth) lead (see Chapter 5A). 18.3a Unscrew the mounting nuts . . . 11 18.3b . . . then withdraw the lock from inside the bootlid 18.3c Remove the exterior handle and gasket from the outside of the bootlid 3510 Vauxhall/Opel Omega 18.7 Unscrew the securing screws, then remove the lock mechanism from the bootlid 11•18 Bodywork and fittings 19.5 Extract the clips (arrowed) from the tailgate hinge pivot pins 2 Unplug the tailgate wiring harness connector. 3 Disconnect the tailgate washer hose. 4 Have an assistant support the tailgate, then disconnect the tops of the support struts by prising out the spring clips with a small screwdriver. Lower the struts to the body. 5 Extract the clips from the hinge pivot pins, then drive out the pins with a suitable drift while the assistant supports the tailgate. Withdraw the tailgate from the body (see illustration). tighten the bolts and refit the trim. If necessary, adjust the position of the rubber supports so that the tailgate is flush with the surrounding bodywork. After making adjustments, check that the striker enters the lock centrally and if necessary loosen the striker bolts to reposition it. Remove the rear trim panel where necessary. Tighten the bolts and refit the trim on completion. Refitting Support struts Door servo motor Removal Removal and refitting 7 Open the tailgate and note which way round the struts are fitted. Have an assistant support the tailgate in its open position. 8 Using a small screwdriver, prise the spring clip from the top of the strut and disconnect it from the ball on the tailgate. 9 Unbolt the strut lower mounting bracket from the bodywork and remove the strut from the vehicle. Refitting 10 Refitting is a reversal of removal. 20 Tailgate lock components removal and refitting Refitting 6 Refitting is a reversal of removal, but check that when closed the tailgate is positioned centrally within the body aperture and flush with the surrounding bodywork. If necessary, remove the trim from the rear of the roof headlining and loosen the hinge mounting bolts. Reposition the tailgate then 2 Lock mechanism Removal 1 Open the tailgate and remove the trim panel. 2 Remove the tailgate lock cylinder as described later in this Section. 3 Using a Torx key unscrew the mounting bolts then withdraw the lock from the tailgate. 4 Refitting is a reversal of removal. Lock cylinder assembly Removal 21.1b . . . then unhook the link rod (arrowed) and detach the servo motor from the lock mechanism 5 Open the tailgate and remove the trim panel. 6 Disconnect the central locking linkage by prising up the plastic retainer. 7 Unscrew the mounting nuts, then unhook the lock cylinder assembly from the lock linkage rod and remove from the tailgate. 21.7 Disconnect the central locking link rod from the servo motor 3510 Vauxhall/Opel Omega 21 Central locking system components removal and refitting 3 1 Remove the relevant door locks, as described in Section 13. Undo the screws, unhook the link rod and detach the servo motor from the lock mechanism (see illustrations). Control unit Note: On model built from 1996 onwards, the central locking control unit is combined with the anti-theft warning system. Removal Refitting 21.1a Undo the screws (arrowed) . . . 8 Refitting is a reversal of removal. 2 Remove the trim panel from the right-hand front footwell. 3 Release the catch and disconnect the wiring from the bottom of the control unit. 4 Unscrew the mounting nuts and remove the control unit from the vehicle. Refitting 5 Refitting is a reversal of removal, but tighten the mounting nuts securely. Bootlid servo motor Removal 6 Undo the screws, release the clips and remove the bootlid trim panel, as described earlier in this Section. 7 Disconnect the central locking link rod from the servo motor by prising up the plastic retainer (see illustration). 8 Disconnect the wiring connector(s) from the motor, then unscrew the mounting bolts and remove the servo motor from the bootlid (see illustrations). Refitting 9 Refitting is a reversal of removal, but tighten the mounting bolts securely. 21.8a Unscrew the mounting bolts . . . Bodywork and fittings 11•19 Tailgate servo motor Removal 10 Open the tailgate and remove the trim panel. 11 Disconnect the servo motor linkage from the lock cylinder by prising up the plastic retainer. 12 Unscrew the mounting bolts. 13 Disconnect the wiring connector from the motor and remove the servo motor from the tailgate. Refitting 14 Refitting is a reversal of removal, but tighten the mounting bolts securely. 21.8b and remove the servo motor from the bootlid 21.15 Disconnect the wiring plug from the servo motor 21.16a Unscrew the two mounting bolts . . . 21.16b . . . and remove the servo motor and bracket from the bodywork Fuel filler flap servo motor Removal 15 Open the right-hand side luggage compartment side trim lid. Disconnect the wiring plug from the servo motor (see illustration). 16 Unscrew the two mounting bolts and remove the servo motor and bracket from the bodywork. Withdraw from inside the vehicle (see illustrations). Refitting 17 Refitting is a reversal of removal. Ensure that the servo motor locking rod passes through the grommet in the bodywork and engages with the filler flap lock plate (see illustrations). 22 Electric window components - removal and refitting 3 Note: Disconnect the battery negative cable before starting work. After reconnecting the battery, renewing fuses or reconnecting the window winder wiring plugs, each window winder motor must be reprogrammed, as described at the end of this Section. Centre console control switch Removal Note: On models with rear passenger compartment heating vents, it will be necessary to remove the centre console, as described in Chapter 11, to gain access to the switch wiring connectors. 1 Unclip the gear lever gaiter from the centre console and fold it upwards over the gear lever knob. 2 On models with automatic transmission, carefully prise the winter driving mode switch unit and the gear position indicator unit from the centre console. 3 Undo the securing screws and remove the trim panel from the top of the console. 4 Trace the window switch wiring back to its respective connectors and unplug them. 5 Carefully lever the switch unit from the centre console moulding. Refitting Window winder motor 6 Refitting is a reversal of removal. Removal Rear door control switch 13 Remove the window regulator described in Section 14. 14 Unbolt the motor from the regulator. Removal 7 Use a small screwdriver to carefully prise off the ashtray unit from the armrest. 8 Unclip the trim panel from behind the door lock release handle. 9 Carefully prise the grip from the underside off the door pull handle, unscrew and remove the door pull handle retaining screws and then remove the pull handle from the door. 10 Unplug the window switch wiring connector as it becomes accessible. 11 Unclip the switch from the door pull handle assembly. Refitting 12 Refitting is a reversal of removal. as Refitting 15 Refitting is a reversal of removal. Programming 16 After refitting a window winder motor or reconnecting the battery, each motor must be programmed in its fully closed position. 17 With the ignition switched on, close all doors. 18 Working on each window in turn, completely close the window by pressing and holding down the rocker switch; keep the switch held the switch down for at least 5 more seconds after the window has reached the full closed position. 11 21.17a Ensure that the servo motor locking rod passes through the grommet in the bodywork . . . 3510 Vauxhall/Opel Omega 21.17b . . . and engages with the filler flap lock plate 11•20 Bodywork and fittings 23.1a Carefully prise off the triangular plastic cover panel at the rear of the mirror mountings . . . 23.1b . . . and remove the foam padding 23.5a Unscrew the three mounting bolts (arrowed) . . . 23.5b . . . and lift the mirror from the door 23.7 Gently press the upper inner corner of the glass inwards so that the lower outer corner protrudes from the mirror housing 23.8 Unclip the mirror glass from its mountings 8 Unclip the mirror glass from its mountings (see illustration). 9 Disconnect the mirror heating wiring and withdraw the mirror from the housing (see illustration). Exterior mirror housing the heads of the door handle surround securing screws. Undo the screws and remove the door pull handle (see Section 13). Locate the mirror wiring harness and unplug it at the connector. 5 Support the mirror then unscrew the three mounting bolts and lift the mirror from the door (see illustrations). Removal Refitting 1 Carefully prise off the triangular plastic cover panel at the rear of the mirror mountings, then remove the foam padding and unplug the wiring from the tweeter unit (see illustrations). 2 Prise the plastic cover from the inside of the interior door handle. 3 Carefully prise the grip from the door pull handle. 4 Prise off the small plastic covers to expose 6 Refitting is a reversal of removal. Ensure that the door weather strip fits over the outside of the mirror casing. 23.9 Disconnect the mirror heating wiring 23.12a Undo the two screws . . . 23 Exterior mirrors and associated components removal and refitting 3 Mirror glass Removal 7 Gently press the upper inner corner of the glass inwards so that the lower outer corner protrudes from the mirror housing (see illustration). 3510 Vauxhall/Opel Omega Refitting 10 Refitting is a reversal of removal. Carefully press the mirror into the housing until the centre retainer engages. Servo motor Removal 11 Remove the mirror glass as described earlier in this Section. 12 Undo the two screws and withdraw the servo motor from the mirror housing. Unplug the wiring at the connector (see illustrations). 23.12b . . . and withdraw the servo motor from the mirror housing Bodywork and fittings 11•21 23.12c Unplug the wiring at the connector 23.21a Undo the screws . . . 23.21b . . . and lift off the mirror housing frame 23.22a Remove the screws . . . 23.22b . . . and detach the cover from the front of the mirror housing Refitting 13 Refitting is a reversal of removal. Mirror door switch Removal 14 Carefully prise off the triangular plastic cover panel at the rear of the mirror mountings, then remove the foam padding and unplug the wiring from the tweeter unit. 15 Prise the plastic cover from the inside of the interior door handle. 16 Carefully prise the grip from the door pull handle. 17 Prise off the small plastic covers to expose the heads of the door handle surround securing screws. Undo the screws and remove the door pull handle. 18 Disconnect the wiring from the rear of the mirror switch, then depress the locking tabs and remove the switch from the door pull handle assembly. On Estate models the rear quarter window glass incorporates a breakage sensor which is linked to the anti-theft security system, and the rear screen incorporates an aerial for the radio. Refitting 19 Refitting is a reversal of removal. Mirror cover 25 Sunroof components removal and refitting Removal 20 Remove the mirror glass and motor as described earlier in this Section. 21 Undo the screws and lift off the mirror housing frame (see illustrations). 22 Remove the screws and detach the cover from the front of the mirror housing (see illustrations). Refitting 23 Refitting is a reversal of removal. 24 Windscreen and fixed window glass general information The windscreen, rear/tailgate screen and rear quarter window glass (Estate models) are cemented in position with a special adhesive and require the use of specialist equipment for their removal and refitting. Renewal of such fixed glass is considered beyond the scope of the home mechanic. Owners are strongly advised to have the work carried out by a windscreen fitting specialists. 3 Sunroof glass Sunroof interior screen Removal 6 Remove the sunroof glass as described earlier in this Section. 7 Undo the screws and remove the water gutter from the front of the roof aperture. 8 Remove the front sliders, then pull the screen forwards and remove the rear sliders. 9 Withdraw the screen from the roof. Refitting 10 Refitting is a reversal of removal. Removal Wind deflector 1 Slide back the sun screen and half open the sunroof. 2 Undo the screws from the rear edge of the sunroof and remove the trim. 3 Close the sunroof then unclip the side trim using a screwdriver. 4 Mark the position of the side screws then unscrew them and withdraw the glass. Removal Refitting Refitting 5 Refitting is a reversal of removal; ensure that the safety code labelling on the glass is positioned towards the rear of the sunroof aperture. Adjust the height of the glass as follows. With the side screws loose, position the glass so that the front edge is flush with the front of the roof or a maximum of 1.0 mm below the roof and the rear edge is flush with the rear of the roof or a maximum of 1.0 mm above the roof. Tighten the screws to the specified torque with the glass in this position. 13 Refitting is a reversal of removal. 3510 Vauxhall/Opel Omega 11 Half open the glass then undo the screws and detach the deflector lifter mechanism from the front of the sunroof aperture. 12 Rotate the deflector so that it is positioned vertically, then release the deflector from the lifter mechanism. Sunroof motor, gear housing and control switch assembly Removal 14 Set the sunroof glass in the closed position, then disconnect the battery negative cable. 15 Unclip the cover panel from the sunroof control console (see illustration). 11 11•22 Bodywork and fittings 25.15 Unclip the cover panel from the sunroof control console 16 Detach the control knob from the sunroof switch (see illustration). 17 Remove the lens, then unclip the interior lamp unit from the console and disconnect the wiring (see illustrations). 18 Release the control switch from the panel by depressing the clips with a screwdriver (see illustration). 19 Release the sealing strip from the front of the console (see illustration). 20 Undo the securing screws located inside the interior lamp recess, then detach the console from the roof (see illustrations). 21 Slacken and withdraw the motor assembly securing screws, then unplug the wiring connector and remove the assembly from the roof. 25.16 Detach the control knob from the sunroof switch Refitting 22 Refitting is a reversal of removal. If a new motor assembly is being installed, unclip the protective cap and dummy knob from the sunroof switch shaft before fitting. On completion, adjust the operation of the control switch as described in the next sub-section. Adjustment 23 Turn the ignition switch to position II. 24 Press and hold the sunroof switch until the sunroof closes and the motor is heard to stop turning. Release the switch. 25 Turn the sunroof switch to the tilt position - the motor should set the sunroof in the tilt position. 26 Press and hold the sunroof switch until the sunroof closes and the motor is heard to stop turning. Release the switch. 27 Turn the sunroof switch to the fully open position - the motor should slide the sunroof glass back to the fully open position. 28 Turn the sunroof switch to the closed position - the motor should slide the sunroof glass forward. 29 Press and hold the sunroof switch until the sunroof closes completely and the motor is heard to stop turning. Release the switch. 30 The preceding steps should allow the sunroof motor control electronics to learn the open, closed and tilt positions of the sunroof glass. If at any time during the adjustment procedure, the sunroof glass opens unexpectedly, repeat the steps in paragraphs 25 to 30 inclusive as necessary, until operation is satisfactory. Sunroof assembly and control cables Removal and refitting 31 Removal and refitting of the complete sunroof assembly and control cables is considered beyond the scope of the average home mechanic as it involves the removal of the headlining. This work should therefore be carried out by a Vauxhall/Opel dealer. Note: In an emergency, the sunroof glass can be operated by removing the cover panel and turning the manual drive shaft with a screwdriver (see illustration). 25.17a Remove the lens, then unclip the interior lamp unit from the console . . . 25.17b . . . and disconnect the wiring 25.18 Release the control switch from the panel by depressing the clips with a screwdriver 25.19 Release the sealing strip from the front of the console 25.20a Undo the securing screws located inside the interior lamp recess . . . 25.20b . . . then detach the console from the roof 3510 Vauxhall/Opel Omega Bodywork and fittings 11•23 25.31 In an emergency, the sunroof glass can be operated by removing the cover panel and turning the manual drive shaft with a screwdriver 26 Body exterior fittings removal and refitting 5 Water deflector panel Removal 1 Open the bonnet then remove the windscreen wiper arms as described in Chapter 12. 2 Pull the rubber weatherstrip from the front of the bulkhead. 3 Release the rubber sealing strip from the lower edge of the windscreen. 4 Prise off the plastic caps, the slacken and withdraw the panel securing screws. 5 Pull the water deflector panel from the bulkhead, noting that it is in two sections. Refitting 6 Refitting is a reversal of removal. Wheel arch liners Removal and refitting 7 The wheel arch liners are secured by a combination of self-tapping screws, push-fit clips and nuts. Removal is self-evident after supporting the vehicle on axle stands and removing the roadwheel (see Jacking and Vehicle Support). The clips are removed by pushing the centre pins through, and are secured by inserting the centre pins and pushing them in flush. 27.2a Undo the securing screw . . . 27.2b . . . and detach the plastic end cap from the outer seat runners Body trim strips and badges Removal and refitting 8 The various body trim strips and badges are held in position with a special adhesive. Removal requires the trim/badge to be heated, to soften the adhesive, and then cut away from the surface. Due to the high risk of damage to the vehicle paintwork during this operation, it is recommended that this task should be entrusted to a Vauxhall/Opel dealer. 27 Seats removal and refitting 2 Front seat Warning: The front seats are fitted with seat belt tensioners and on some models, side impact air bags. Before removing the front seats, the seat belt tensioners and side impact airbags must be disabled - refer to the Supplementary Restraint System (SRS) safety information given in Chapter 12, Section 23 before proceeding. Removal 1 Ensure that the Supplementary Restraint System (SRS) is disabled before proceeding; refer to Chapter 12 Section 23 for details. 2 Undo the securing screw and detach the plastic end cap from the outer seat runner. Unclip the trim panel from the side of the seat runner (see illustrations). 27.2c Unclip the trim panel from the side of the seat runner 3 On models with mechanical seat belt tensioners, ensure that the special locking tool is inserted to prevent the accidental triggering of the tensioner mechanism; refer to the Supplementary Restraint System (SRS) safety information given in Chapter 12, Section 23 before proceeding. 4 Adjust the seat to the fully forwards position, then unscrew the rear mounting screws (see illustration). 5 Slide the seat backwards to the end of its travel, then unscrew the front mounting screws (see illustration). 6 Unplug the wiring at the connector(s) and remove the front seat from inside the vehicle (see illustrations). Refitting 7 Refitting is a reversal of removal but use new mounting screws and tighten them to the 11 27.4 Unscrew the seat rear mounting screws 27.5 Unscrew the seat front mounting screws 3510 Vauxhall/Opel Omega 27.6a Unplug the wiring at the connector(s) . . . 11•24 Bodywork and fittings 27.6b . . . and remove the front seat from inside the vehicle specified torque in the sequence shown (see illustration) On models with mechanical seat belt tensioners, remove the forked locking tool before refitting the seat runner trim panels. Rear seat cushion Removal 8 Grasp the seat cushion lock straps, located at the front lower edge of the seat , and pull them to disengage the locks (see illustration). 9 Pivot the seat cushion backwards and unplug the wiring for the heating elements (where fitted). 10 Pass the seat belt buckles through the hole in the seat cushion, then remove the seat from the vehicle (see illustration). 27.7 Front seat bolt tightening sequence 15 Press the release buttons and allow the seat back to pivot forwards. 16 Unclip the carpet trim from rear bulkhead, then unscrew the hinge bolts and remove the rear seat back from the car. Where applicable, unplug the seat heating element wiring at the connector. back rest, recovering the washers, and remove the back rest from the vehicle. 21 Where a split rear seat back rest is fitted, undo the pivot bolts at both ends of the back rest, recovering the washers, then unbolt the centre hinges from the support bracket and remove the back rest from the vehicle. 11 Refitting is a reversal of removal. Ensure that the seat belt buckles pass through the hole in the seat cushion before locking it in position. Refitting Refitting 17 Refitting is a reversal of removal. Ensure that all fixings are tightened to the correct torque, where specified. 22 Refitting is a reversal of removal. Ensure that all fixings are tightened to the correct torque, where specified. Rear seat backrest Saloon models Rear seat back Estate models Removal Removal 12 Remove the rear seat cushion, as described earlier in this Section. 13 Depress the locking button and detach the centre seat belt from its buckle. 14 Bend up the metal securing tabs, then pivot the side cushions upwards and remove them from the car (see illustration). 18 Remove the rear seat cushion, as described earlier in this Section. 19 Depress the locking button and detach the centre seat belt from its buckle (where fitted). 20 Where a single-section seat back rest is fitted, undo the pivot bolts at both ends of the 27.8 Pull the seat cushion lock straps 27.10 Remove the seat cushion from the vehicle Refitting 3510 Vauxhall/Opel Omega 28 Seat belt components removal and refitting 3 Front seat belt and reel Removal 1 Prise off the cap, then slacken and withdraw the bolt and detach the seat belt 27.14 Bend up the metal securing tabs to release the seat back side cushions Bodywork and fittings 11•25 28.1a Prise off the cap . . . 28.1b then slacken and withdraw the bolt and detach the seat belt lower anchor from the sill 28.2 Unclip and remove the B-pillar lower trim panel lower anchor from the sill. Recover the washers (see illustrations). 2 Unclip and remove the B-pillar lower trim panel (see illustration). 3 Unclip the alarm system interior sensor unit from the B-pillar upper trim panel and unplug the wiring at the connector (see illustration). 4 Undo the screws and remove the B-pillar upper trim panel. Feed the seat belt clasp through the trim panel aperture (see illustrations). 5 Prise the cover strip from the sill trim panel. Undo the screws and remove the panel from the sill (see illustrations). 6 Slacken and withdraw the bolt and detach the seat belt upper anchor from the adjustment bar slider (see illustration). 7 Unbolt the inertia reel from the base of the B-pillar and remove the seat belt assembly from the vehicle (see illustration). Refitting 28.3 Unclip the alarm system interior sensor unit from the B-pillar upper trim panel . . . 28.4a Undo the screws and remove the Bpillar upper trim panel 28.4b Feed the seat belt clasp through the trim panel aperture 28.5a Prise the cover strip from the sill trim panel 28.5c . . . and remove the panel from the sill 28.6 Slacken and withdraw the bolt (arrowed) and detach the seat belt upper anchor from the adjustment bar slider 8 Refitting is a reversal of removal, but tighten all mounting bolts to the correct torque, where specified. 28.5b Undo the screws . . . 11 3510 Vauxhall/Opel Omega 28.7 Inertia reel securing bolt 11•26 Bodywork and fittings 28.9a Unclip the cover from the parcel shelf . . . Rear seat belt and reel Saloon models Removal 9 The centre rear seat belt can be removed by unclipping the cover from the parcel shelf, unbolting the inertia reel and then depressing the locking button to release the lower belt anchor from its buckle (see illustrations). 10 The outer seat belts are removed as follows. Refer to Section 27 and remove the rear seat cushion and backrests. 11 Slacken and withdraw the bolt and detach the seat belt lower anchor from the bodywork. 12 Remove the cap then slacken and withdraw the bolt and detach the seat belt upper anchor from the bodywork. 13 Unbolt the inertia reel from the C-pillar and remove the seat belt assembly from the vehicle (see illustration). Refitting 14 Refitting is a reversal of removal, but tighten all mounting bolts to the correct torque, where specified. Rear seat belt and reel Estate models Removal 15 To remove the centre seat belt, first remove the rear seat back as described in Section 27. Remove the upholstery from the seat back by releasing the securing clips. The inertia reel can then be unbolted, allowing the seat belt to be removed. 16 The outer seat belts are removed as 28.9c . . . and then depress the locking button to release the lower belt anchor from its buckle 28.9b . . . unbolt the inertia reel . . . follows. Refer to Section 27 and remove the rear seat cushion and backrests. 17 Slacken and withdraw the bolt and detach the seat belt lower anchor from the bodywork. 18 Remove the cap, slacken and withdraw the bolt and detach the seat belt upper anchor from the bodywork. 19 Release the securing clips and detach the lower trim panel from the C-pillar. Similarly, remove the trim panel from the side of the load space. 20 Unbolt the inertia reel from the bodywork and remove the seat belt assembly from the vehicle. Refitting 3 10 Refitting is a reversal of removal. Sill inner trim panel 11 Remove the B-pillar lower trim panel as described earlier in this Section. 12 Prise the cover strip from the centre of the sill trim panel. 13 Undo the screws and unclip the panel from the sill. Refitting 14 Refitting is a reversal of removal. 1 The interior trim panels are secured by a combination of clips and screws. Removal and refitting is generally self-explanatory, noting that it may be necessary to remove or loosen surrounding panels to allow a particular panel to be removed. The following paragraphs describe the removal and refitting of the major panels in more detail. Front footwell side trim panel Removal 2 Open the front door and pull the weatherstrip away from the side trim panel. Loosen the front end of the sill trim panel, as described later in this Section. 3 Undo the screws, then pull the bonnet release handle forwards and remove the side trim panel. Refitting 4 Refitting is a reversal of removal. B-pillar trim panel Removal 28.13 Unbolting the outer rear seat belt inertia reel from the C-pillar Refitting Removal 21 Refitting is a reversal of removal, but tighten the mounting bolts to the specified torque. 29 Interior trim removal and refitting adjuster mechanism with reference to Section 28. 7 Pull the door weatherstrip away from the trim. 8 Release the press-stud clips with a flat bladed instrument and prise the lower trim panel from the B-pillar. 9 Undo the screws, then remove the upper trim panel from the B-pillar, feeding the seat belt buckle through the slot. 5 Where fitted, carefully lever off the alarm system sensor and disconnect the wiring. 6 Unbolt the front seat belt from the height 3510 Vauxhall/Opel Omega Luggage compartment side trim panel (Estate models) Removal 15 Remove the rear luggage compartment cover, then remove the rear seat as described in Section 27. 16 Slacken and withdraw the securing screws and remove the C-pillar lower trim panel. 17 Undo the screws then prise out the side trim panel using a screwdriver to release the retaining clips. Refitting 18 Refitting is a reversal of removal. Luggage compartment side trim panel (Saloon models) Removal 19 Open the bootlid and remove the vehicle tools. 20 Fold the rear seat backrest forwards, then prise the rubber beading from the edge of the rear bulkhead aperture. 21 Unclip the rubber cap from the top of the rear suspension strut mounting nut. Bodywork and fittings 11•27 22 Lift the carpet trim from the floor of the loadspace, then unclip the cover from the spare wheel. 23 Remove the trim panel from the side of the luggage compartment. Refitting 24 Refitting is a reversal of removal. Carpets Removal 25 The front and rear carpets can be removed after removing the front seats, centre console and rear footwell air distribution ducts together with side trim panels and remaining brackets. 26 On Estate models the rear luggage compartment carpet can be removed by releasing the clips located on the backrest and rear valance then removing the tools and spare wheel cover. Refitting 27 Refitting is a reversal of removal. 30.2a Open the lid of the storage box to the rear of the handbrake lever, then undo the four screws . . . 30.2b . . . and withdraw the storage box moulding from the console considerable skill and experience if it is to be carried out without damage, and is therefore best entrusted to an expert. mounting bracket, then unplug the wiring harness and remove the bracket from the console. 4 Remove the screws and detach the rear passenger air vent module (where fitted) from the rear of the console (see illustrations). Unplug the wiring at the connector(s). 5 Unclip the gear lever gaiter from the console and fold it up over the gear lever knob (see illustration). 6 On automatic models, prise the gear position indicator module and winter mode switch module from the console (see illustrations). Unplug the wiring at the connectors. 7 Undo the securing screws and remove the gear lever trim panel from the surround (see illustrations). 30 Centre console removal and refitting 2 Headlining 28 The headlining is secured to the roof with clips and screws, and can be withdrawn once all fittings such as the grab handles, sun visors, sunroof, front, centre and rear pillar trim panels, and associated components have been removed. The door and tailgate aperture weatherseals will also have to be prised clear. 29 Note that headlining removal requires 30.4a Remove the screws . . . Removal 1 Disconnect the battery negative (earth) lead (see Chapter 5A). 2 Open the lid of the storage box to the rear of the handbrake lever, then undo the four screws and withdraw the storage box moulding from the console (see illustrations). 3 Where applicable, unbolt the car telephone 30.4b . . . and detach the rear passenger air vent module (where fitted) from the rear of the console 30.4c Unplug the wiring at the connector(s) 11 30.5 Unclip the gear lever gaiter from the console and fold it up over the gear lever knob 30.6a On automatic models, prise the gear position indicator module . . . 3510 Vauxhall/Opel Omega 30.6b . . . and winter mode switch module from the console 11•28 Bodywork and fittings 30.7a Undo the securing screws . . . 30.7b . . . and remove the gear lever trim panel from the surround 30.8 Unclip the gaiter from the handbrake lever and remove it 30.9a Slacken and withdraw the securing screws . . . 30.9b . . . and lift off the centre arm rest (where fitted) 30.10a Undo the centre console securing screws . . . 30.10b . . . remove the support bracket . . . 30.10c . . . then lift the console away from the floorpan 8 Unclip the gaiter from the handbrake lever and remove it (see illustration). 9 Slacken and withdraw the securing screws and lift off the centre arm rest (where fitted) (see illustrations). 10 Undo the centre console securing screws, remove the support bracket, then lift the console away from the floorpan. Unplug the electric window switch wiring at the connectors, as it becomes accessible (see illustrations). 11 Remove the console from the vehicle. Note that on automatic models, it may be necessary to release the gear selector from the P position, by depressing the yellow release lever, to allow the removal of the console from the floorpan (see illustration). Refitting 12 Refitting is a reversal of removal. 31 Glovebox removal and refitting 2 Removal 30.11 On automatic models, it may be necessary to release the gear selector from the PARK position, by depressing the yellow release lever, to allow the removal of the console from the floorpan 31.2 Release the press-stud clips and detach the trim panel from the underside of the facia 3510 Vauxhall/Opel Omega 1 Disconnect the battery negative cable and position it away from the terminal. 2 Release the press-stud clips and detach the trim panel from the underside of the facia (see illustration). 3 Slacken and withdraw the screws that secure the lower edge of the passenger airbag Bodywork and fittings 11•29 31.3 Slacken and withdraw the screws that secure the lower edge of the passenger airbag unit cover panel to the facia 31.4 Undo the glovebox mounting screws (arrowed) unit cover panel to the facia - there is no need to remove the cover panel completely (see illustration). Refer to Chapter 12 Section 24 for details of the passenger air bag unit cover. 4 Open the glovebox lid, then lift the passenger airbag unit cover panel slightly and undo the glovebox upper mounting screws, to release the top of the glovebox to the facia panel (see illustration). 5 Undo the two lower screws and withdraw the glovebox from the facia panel sufficient to disconnect the wiring from the illumination lamp and its switch. 6 On models fitted with air conditioning detach the air hose from the cooling slider. 7 Withdraw the glovebox from the facia and remove it from the facia. that the passenger airbag unit cover panel securing screws and tightened to the specified torque. Refitting 8 Refitting is a reversal of removal. Ensure 32.9a Open the fusebox cover and unhook the check strap from it 32 Facia assembly removal and refitting 4 Removal Warning: Refer to the Supplementary Restraint System (SRS) precautions given in Chapter 12 Section 23 before disturbing the driver or passenger airbag units. 1 Note that this procedure involves the removal of the driver and passenger airbag units. Before proceeding, carry out the Supplementary Restraint System (SRS) 32.9b Pull out the hinge pins . . . deactivation procedure, as described in Chapter 12 Section 23. Failure to carry out this procedure may result in accidental detonation of the airbag(s). 2 Remove the drivers airbag unit from the steering wheel as described in Chapter 12 Section 24. 3 Set the steering wheel in the straight ahead position, then remove the ignition key and allow the steering column lock to engage. Ensure that the steering column remains in this position throughout the entire procedure. 4 Remove the steering wheel as described in Chapter 10. 5 Undo the screws and remove the upper and lower sections of the steering column cowling. 6 Remove the wiper and indicator switches from the steering column as described in Chapter 12, Section 4. Unbolt and remove the switch plastic mounting bracket. 7 Remove the ignition switch unit from the rear of the steering column lock assembly, with reference to Chapter 10. 8 Remove the airbag contact unit as described in Chapter 12 Section 24. 9 At the underside of the steering column, unclip and remove the lower trim panel, then open the fusebox cover and unhook the check strap from it. Pull out the hinge pins and remove the fusebox cover from the facia (see illustrations). 10 Carefully lever the cover panel from the side of the right hand facia end section (see illustration). 11 Remove the headlamp switch unit, as described in Chapter 12, Section 4. 12 Unclip the headlamp switch base plate from the facia end section. 13 Unclip the bulb holder from the rear of the air vent housing and position it to one side (see illustration). 14 Unclip the air vent nozzle from its housing, then undo the screws and remove the air vent/headlamp switch housing (see illustrations). 15 Slacken and withdraw the securing screws and remove the right hand facia end section (see illustrations). 16 Remove the glovebox as described in Section 31. 11 32.9c . . . and remove the fusebox cover from the facia 32.10 Lever the cover panel from the side of the right hand facia end section 3510 Vauxhall/Opel Omega 32.13 Unclip the bulb holder from the rear of the air vent housing 11•30 Bodywork and fittings 32.14a Unclip the air vent nozzle from its housing . . . 32.14b . . . then undo the screws . . . 32.14c . . . and remove the air vent/headlamp switch housing 17 Unclip the cover panel from the left hand facia end section. 18 Unclip the bulb holder from the rear of the air vent housing and position it to one side. 19 Slacken and withdraw the securing screws then detach the nozzle from the left hand air vent housing (see illustrations). 20 Undo the securing screws and remove the left hand end section from the facia (see illustrations). 21 Remove the passenger airbag as described in Chapter 12 Section 24, then unbolt and remove the passenger airbag mounting bracket. 22 Carefully prise the two nozzles from the 32.15a Slacken and withdraw the securing screws . . . 32.15b . . . and remove the right hand facia end section 32.19a Slacken and withdraw the securing screws . . . 32.19b . . . then detach the nozzle from the left hand air vent housing 32.20a Undo the securing screws . . . 32.20b . . . and remove the left hand end section from the facia 32.22a Carefully prise the two nozzles from the centre air vent housing . . . 32.22b . . . then undo the securing screws . . . 32.22c . . . and remove the vent housing from the facia 3510 Vauxhall/Opel Omega Bodywork and fittings 11•31 32.29a Release the main wiring harness from the mounting on the facia, behind the relay base plate, by compressing the press-stud clip with a pair of pliers . . . 32.29b . . . release the three clips from the panel behind the heater/ECC control panel mounting aperture in a similar manner centre air vent housing, then undo the securing screws and remove the vent housing from the facia (see illustrations). 23 Remove the instrument pack as described in Chapter 12 Section 9. 24 Remove the heater control panel (or Electronic Climate Control panel, as applicable) from the facia as described in Chapter 3. 25 Remove the centre console as described in Section 30. 26 Slacken and withdraw the screws securing the fusebox panel and the relay panel to the facia. Pull the panels away from the facia slightly, leaving the wring harnesses attached. 27 Working underneath the facia on the passengers side, remove the securing screws and detach the moulded air duct that runs from the air distributor unit to the left hand end of the facia. 28 Withdraw the exit vent and disconnect the moulded air ducting that runs from the air distributor housing to the right hand end of the facia. 29 Release the main wiring harness from the mounting on the facia, behind the relay base plate, by compressing the press-stud clip with a pair of pliers and pushing it through its mounting hole. Release the three clips from the panel behind the heater/ECC control panel mounting aperture in a similar manner (see illustrations). 30 Release the main wiring harness from the cable tie clips, located inside the facia, above the transmission tunnel. Access to the clips (via the radio/cassette mounting aperture) is extremely limited. Take great care to avoid damaging the wiring harness during this operation, as the air bag control unit wiring is routed through this section of the harness. 31 Remove the Electronic Climate Control (ECC) sun sensor from the top of the facia (where applicable) with reference to Chapter 3, Section 13. 32 Unbolt and remove the driver and passenger grab handles, then unclip the trim panels from both A-pillars (see illustrations). 33 Slacken and withdraw the facia securing bolts; there are seven bolts in total: one at the lower edge of the facia, in front of the gear lever, two each at the extreme right and left hand ends of the facia, one behind the instrument panel mounting aperture, and one adjacent to the upper right hand corner of the passenger air bag mounting bracket aperture. 34 Carefully withdraw the facia from the bulkhead, ensuring that the wiring harness has been completely released from the rear of the facia assembly (see illustration). Remove the assembly from the vehicle. 32.32a Unbolt and remove the driver and passenger grab handles . . . 32.32b . . . then unclip the trim panels from both A-pillars 32.34 Carefully withdraw the facia from the bulkhead Refitting 35 Refit the facia by following the reversal procedure in reverse. If a new facia assembly is to be fitted, make sure that the airbag warning stickers are transferred from the old facia. 11 3510 Vauxhall/Opel Omega