BMW 335 User Manual

BMW 3- & 5-Series

Service and Repair Manual

A K Legg LAE MIMI and Larry Warren

Models covered

3-Series (E30)

316 (83 to 88), 316i (88 to 91), 318i (83 to 91), 320i (87 to 91), 325i (87 to 91). Also Touring and Convertible versions of these models

5-Series (E28)

518 (81 to 85), 518i (85 to 88), 525i (81 to 88), 528i (81 to 88), 535i (85 to 88), M535i (85 to 88)

5-Series (E34)

518i (90 to 91), 520i (88 to 91), 525i (88 to 91), 530i (88 to 91), 535i (88 to 91)

Engines covered

1596 cc, 1766 cc, 1795 cc, 1990 cc, 2494 cc, 2788 cc, 2986 cc & 3430 cc

Does not cover Diesel, dohc or V8 engines, or four-wheel-drive models

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.

ISBN 1 85960 236 3

British Library Cataloguing in Publication Data

A catalogue record for this book is available from the British Library.

Printed by J H Haynes & Co. Ltd, Sparkford, Nr Yeovil,Somerset

BA22 7JJ, England Haynes Publishing

Sparkford, Nr Yeovil, Somerset BA22 7JJ, England

Haynes North America, Inc

861 Lawrence Drive, Newbury Park, California 91320, USA

Editions Haynes S.A.

147/149, rue Saint Honoré, 75001 PARIS, France

Haynes Publishing Nordiska AB

Box 1504, 751 45 Uppsala, Sweden

(1948-256-11AA3)

ABCDE FGHIJ KLMNO PQRST

1 2 3

LIVING WITH YOUR BMW

Introduction Page 0•4 Safety First! Page 0•6 Anti-theft audio system Page 0•7 Instrument panel language display Page 0•7

Roadside Repairs

Jacking, towing and wheel changing Page 0•8 Jump starting Page 0•9 Identifying leaks Page 0•10

ROUTINE MAINTENANCE

Routine Maintenance and Servicing Page 1•1 Lubricants and fluids Page 1•3 Maintenance schedule Page 1•4

Weekly checks Page 1•7 Every 6000 miles Page 1•11 Every 12 000 miles Page 1•16 Every 24 000 miles Page 1•23 Every 60 000 miles Page 1•26

Contents

REPAIRS & OVERHAUL

Engine and Associated Systems

In-car engine repair procedures Page 2A•1 General engine overhaul procedures Page 2B•1 Cooling, heating and air conditioning systems Page 3•1 Fuel and exhaust systems Page 4•1 Engine electrical systems Page 5•1 Engine management and emission control systems Page 6•1

Transmission

Manual transmission Page 7A•1 Automatic transmission Page 7B•1 Clutch and driveline Page 8•1

Brakes

Braking system Page 9•1

Suspension

Suspension and steering systems Page 10•1

Body Equipment

Bodywork and fittings Page 11•1

Electrical

Body electrical systems Page 12•1

Wiring Diagrams Page 12•10

REFERENCE

MOT Test Checks

Checks carried out from the driver’s seat Page REF•1 Checks carried out with the vehicle on the ground Page REF•2 Checks carried out with the vehicle raised Page REF•3

Checks carried out on your vehicle’s exhaust emission system Page REF•4 Tools and Working Facilities Page REF•5 General Repair Procedures Page REF•8 Fault Finding Page REF•9 Conversion factors Page REF•17 Automotive chemicals and lubricants Page REF•18 Buying spare parts and vehicle identification numbers Page REF•19 Glossary of Technical Terms Page REF•20

Index Page REF•25

Contents

0•4

Introduction

The E30 3-Series range first became available in the UK in March 1983, and continued in production until April 1991, when the revised E36 3-Series range (not covered by this manual) was introduced. Convertible and Touring (Estate) models were introduced for 1988, and these models have continued in E30 form to date.

The E28 5-Series models were introduced in October 1981, and were superseded in June 1988 by the revised E34 5-Series range, Touring versions of which became available from March 1992. Throughout this manual, E28 models are also referred to as “oldshape”, while E34 models are designated “new-shape”.

The models covered by this manual are equipped with single overhead cam in-line four- and six-cylinder engines. Early 316 and 518 models are fitted with carburettors, but all other models are fitted with fuel injection systems. Transmissions are a five-speed manual, or three- or four-speed automatic. The transmission is mounted to the back of the engine, and power is transmitted to the fully-independent rear axle through a twopiece propeller shaft. The final drive unit is bolted solidly to a frame crossmember, and drives the rear wheels through driveshafts

equipped with inner and outer constant velocity joints.

The front suspension is of MacPherson strut type, with the coil spring/shock absorber unit making up the upper suspension link. The rear suspension is made up of coil springover-shock absorber struts, or coil springs and conventional shock absorbers, depending on model.

The brakes are disc type at the front, with either drums or discs at the rear, depending on model. Servo assistance is standard on all models. Some later models are equipped with an Anti-lock Braking System (ABS).

All models are manufactured to fine limits, and live up to the BMW reputation of quality workmanship. Although many of the models covered by this manual appear complex at first sight, they should present no problems to the home mechanic.

Note for UK readers

The greater part of this manual was originally written in the USA. Some of the photographs used are of American-market models, but the procedures given are fully applicable to right-hand-drive models (or have been amended where necessary).

Acknowledgements

Thanks are due to Champion Spark Plug, who supplied the illustrations showing spark plug conditions. Thanks are also due to Sykes-Pickavant Limited, who provided some of the workshop tools, and to all those people at Sparkford who helped in the production of this manual. Technical writers who contributed to this project include Robert Maddox, Mark Ryan and Mike Stubblefield.

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.

Project vehicles

The main project vehicle used in the preparation of this manual for the UK market was a 1988 BMW 318i with an M40/B18 engine.

Introduction to the BMW 3- and 5-Series

BMW 320i Saloon (E30)

0•5

Introduction

BMW 518i (E28)

BMW 325i Touring (E30)

BMW 535i (E34)

BMW 325i Convertible (E30)

0•6

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.

Fire

• 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.

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.

• 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.

Asbestos

• 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.

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 use eye protection when using power tools, and when working under the vehicle.

• 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.

A few tips

DON’T

• Don’t attempt to lift a heavy component which may be beyond your capability – get assistance.

• 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•7

Anti-theft audio system

General information

Some models are equipped with an audio system having an anti-theft feature that will render the stereo inoperative if stolen. If the power source to the stereo is cut, the stereo won’t work even if the power source is immediately re-connected. If your vehicle is equipped with this anti-theft system, do not disconnect the battery or remove the stereo unless you have the individual code number for the stereo.

Refer to the owner’s handbook supplied

with the vehicle for more complete information on this audio system and its antitheft feature.

Unlocking procedure

1 T urn on the radio. The word “CODE” should

appear on the display. 2 Using the station preset selector buttons, enter the five-digit code. If you make a mistake when entering the code, continue the five-digit sequence anyway. If you hear a “beep,” however, stop immediately and

start the sequence over again. Note: You

have three attempts to enter the correct code. If the correct code isn’t entered in three tries, you’ll have to wait one hour, with the radio on, before you enter the codes again.

5 Once the code has been entered correctly, the word “CODE” should disappear from the display, and the radio should play (you’ll have to tune-in and enter your preset stations, however). 6 If you have lost your code number, contact a BMW dealer service department.

Instrument panel language display

On some later models, disconnecting the battery may cause the instrument panel display to default to the German language (this does not usually apply to UK models). If it is necessary to reset the correct language after the battery is reconnected, proceed as follows. With all the doors shut and the

ignition on (engine not running), press the trip reset button until the panel displays the desired language. There are eight languages available. If you wish to bypass a particular selection, release the reset button and press again - this will cause the display to advance to the next language. Once the correct

language has been selected, continue holding the reset button until the display reads “I.O. Version 2.0”. Continue holding the button until it reads “H.P. Version 3.4”, then release the button.

0•8

Roadside Repairs

Jacking and wheel changing

The jack supplied with the vehicle should be used only for raising the vehicle when changing a tyre or placing axle stands under the frame.

Warning: Never crawl under the vehicle or start the engine when this jack is being used as the only means of support.

When changing a wheel, the vehicle should be on level ground, with the handbrake firmly applied, and the wheels chocked. Select reverse gear (manual transmission) or Park (automatic transmission). Prise off the hub cap (if equipped) using the tapered end of the wheel brace. Loosen the wheel bolts half a turn, leaving them in place until the wheel is raised off the ground.

Position the head of the jack under the side of the vehicle, making sure it engages with the

pocket made for this purpose (just behind the front wheel, or forward of the rear wheel). Engage the wheel brace handle and turn it clockwise until the wheel is raised off the ground. Unscrew the bolts, remove the wheel and fit the spare.

Refit the wheel bolts and tighten them finger-tight. Lower the vehicle by turning the wheel brace anti-clockwise. Remove the jack and tighten the bolts in a diagonal pattern to the torque listed in the Chapter 1 Specifications. If a torque wrench is not available, have the torque checked by a BMW dealer or tyre fitting specialist as soon as possible. Refit the hubcap.

Towing

Vehicles with manual transmission can be towed with all four wheels on the ground, if necessary. Automatic transmission-equipped vehicles can only be towed with all four

wheels on the ground providing that the speed does not exceed 35 mph and the distance is not over 50 miles, otherwise transmission damage can result. For preference, regardless of transmission type, the vehicle should be towed with the driven (rear) wheels off the ground.

Proper towing equipment, specifically designed for the purpose, should be used, and should be attached to the main structural members of the vehicle, not to the bumpers or bumper brackets. Sling-type towing equipment must not be used on these vehicles.

Safety is a major consideration while towing. The handbrake should be released, and the transmission should be in neutral. The steering must be unlocked (ignition switch turned to position “1”). Remember that power-assisted steering (where fitted) and the brake servo will not work with the engine switched off.

Jacking, towing and wheel changing

0•9

Roadside Repairs

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 Ensure that all electrical equipment

(lights, heater, wipers, etc) 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 vehcles MUST NOT TOUCH each other.

4 Make sure that the transmission is in

neutral (or PARK, in the case of automatic transmission).

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.

The charging system is not working

properly (alternator drivebelt slack or broken, alternator wiring fault or alternator itself faulty).

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

Connect the other end of the red lead to the positive (+) terminal of the booster battery.

Connect one end of the black jump lead to the negative (-) terminal of the booster battery

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.

Make sure that the jump leads will not come into contact with the fan, drivebelts or other moving parts of the engine.

Start the engine using the booster battery, then with the engine running at idle speed, disconnect the jump leads in the reverse order of connection.

Jump starting

0•10

Roadside Repairs

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.

Identifying leaks

The smell of a fluid leaking from the car may provide a clue to what’s leaking. Some

fluids are distinctively 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 Gearbox oil

Brake fluid Power steering fluid

Oil from filter

Antifreeze

Engine oil may leak from the drain plug... ...or from the base of the oil filter.

Leaking antifreeze often leaves a crystalline deposit like this.

Gearbox oil can leak from the seals at the inboard ends of the driveshafts.

A leak occurring at a wheel is almost certainly brake fluid.

Power steering fluid may leak from the pipe connectors on the steering rack.

Engine

Oil filter

M10 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion C121

M20 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion C160

M30 engines

3-Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion C160

5-Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion X115

M40 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion X120

Valve clearances (intake and exhaust)

M10 engines

Cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.20 mm

Hot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.25 mm

M20 engines

Cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.25 mm

Hot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.30 mm

M30 engines

Cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.30 mm

Hot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.35 mm

M40 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic adjusters

Cooling system

Antifreeze mixture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40% antifreeze/60% water

Chapter 1

Routine maintenance and servicing

Air filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Automatic transmission fluid and filter change . . . . . . . . . . . . . . . . . 28

Automatic transmission fluid level check . . . . . . . . . . . . . . . . . . . . . 8

Battery check, maintenance and charging . . . . . . . . . . . . . . . . . . . . 13

Brake system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Cooling system - draining, flushing and refilling . . . . . . . . . . . . . . . . 29

Cooling system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Differential lubricant change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Differential lubricant level check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Driveshaft gaiter check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Drivebelt check, adjustment and renewal . . . . . . . . . . . . . . . . . . . . . 11

Engine idle speed and CO level check and adjustment . . . . . . . . . . 12

Engine oil and filter change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Engine timing belt renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Exhaust system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Evaporative Emissions Control (EVAP) system check . . . . . . . . . . . 33

Fluid level checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Fuel filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Fuel system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Manual transmission lubricant change . . . . . . . . . . . . . . . . . . . . . . . 31

Manual transmission lubricant level check . . . . . . . . . . . . . . . . . . . . 16

Power steering fluid level check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Routine maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Service light resetting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Spark plug check and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Spark plug HT leads, distributor cap and rotor - check

and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Steering and suspension check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Throttle linkage - check and lubrication . . . . . . . . . . . . . . . . . . . . . . 19

Tyre and tyre pressure checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Tyre rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Tune-up general information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Underbonnet hoses - check and renewal . . . . . . . . . . . . . . . . . . . . . 10

Valve clearances - check and adjustment . . . . . . . . . . . . . . . . . . . . 18

Wiper blades - check and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . 27

1•1

Easy, suitable for novice with little experience

Fairly easy, suitable for beginner with some experience

Fairly difficult,

suitable for competent DIY mechanic

Difficult, suitable for experienced DIY mechanic

Very difficult,

suitable for expert DIY or professional

Degrees of difficulty

Specifications

Contents

Fuel system

Idle speed

3-Series, E30

316 with M10/B18 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 850 ± 50 rpm

316i with M40/B16 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 40 rpm

318i with M10/B18 engine (manual transmission) . . . . . . . . . . . . . 850 ± 50 rpm

318i with M10/B18 engine (automatic transmission) . . . . . . . . . . . 750 ± 50 rpm

318i with M40/B18 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 40 rpm

320i with M20/B20 engine (L-Jetronic) . . . . . . . . . . . . . . . . . . . . . . 800 ± 50 rpm

320i with M20/B20 engine (Motronic) . . . . . . . . . . . . . . . . . . . . . . . 760 ± 40 rpm

325i with M20/B25 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 760 ± 40 rpm

5-Series, E28 (“old-shape”)

518 and 518i with M10/B18 engine . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 50 rpm

All other models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 850 ± 50 rpm

5-Series, E34 (“new-shape”)

518i with M40/B18 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 40 rpm

520i with M20/B20M engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 760 ± 40 rpm

525i with M20/B25M engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 760 ± 40 rpm

530i with M30/B30M engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 ± 50 rpm

535i with M30/B35M engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 850 ± 50 rpm

CO% at 3000 rpm

3-Series, E30

316 with M10/B18 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 to 1.0

316i and 318i with M40/B16 engine . . . . . . . . . . . . . . . . . . . . . . . . 0.7 ± 0.5

318i with M10/B18 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 maximum

320i with M20/B20 engine (L-Jetronic) . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.5

320i with M20/B20 engine (Motronic) . . . . . . . . . . . . . . . . . . . . . . . 0.7 ± 0.5

325i with M20/B25 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.5

5-Series, E28 (“old-shape”)

518 and 518i with M10/B18 engine . . . . . . . . . . . . . . . . . . . . . . . . 1.0 maximum

525i with M30/B25 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ± 0.5

528i with M30/B28 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5 maximum

535i with M30/B34 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 to 1.5

M535i with M30/B34 engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 to 1.5

5-Series, E34 (“new-shape”)

All models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.7 ± 0.5

Air filter element

M10 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion W155 (round) or U504 (square)

M20 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U504 or U527

M30 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U504 or U527

M40 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U527

Fuel filter (all fuel injection engines) . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion L206

Ignition system

Spark plug type

M10, M20 and M30 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion N9YCC

M40 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion C9YCC

Spark plug gap* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.8 mm

Spark plug (HT) leads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion type not available

* The spark plug gap quoted is that recommended by Champion for their specified plugs listed above. If spark plugs of any other type are to be

fitted, refer to their manufacturer’s spark plug gap recommendations.

Brakes

Disc brake pad thickness (minimum) . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 mm

Drum brake shoe lining thickness (minimum) . . . . . . . . . . . . . . . . . . . . . 2.0 mm

Wiper blades

Windscreen

3-Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion X-5103

3-Series passenger side from 1991 . . . . . . . . . . . . . . . . . . . . . . . . . . Champion X-5103 (20 inch) or Champion X-5303 (21 inch)

5-Series, E28 (“old-shape”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion X-4503

5-Series, E34 (“new-shape”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion type not available

Tailgate

3-Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion X-4503

5-Series . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion type not available

1•2

Servicing Specifications

Tyre pressures (cold) - bars (psi) Front Rear

3-Series, E30

316 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.9 (28) 2.1 (30)

316i

Saloon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 (29) 2.1 (30)

Estate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 (29) 2.2 (32)

318i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8 (26) 1.9 (28)

320i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.9 (28) 2.0 (29)

325i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 (32) 2.3 (33)

5-Series, E28 (“old-shape”)

518 and 518i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 (29) 2.0 (29)

525i and 528i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 (32) 2.2 (32)

535i and M535i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 (33) 2.5 (36)

5-Series, E34 (“new-shape”)

518i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 (29) 2.0 (29)

520i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 (32) 2.1 (30)

525i, 530i and 535i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 (29) 2.3 (33)

Torque wrench settings Nm

Automatic transmission sump bolts

Three-speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 to 9

Four-speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 to 7

Spark plugs

M10 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 to 30

Except M10 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 to 33

Oxygen sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 to 33

Wheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

Lubricants and fluids

Component or system Lubricant type/specification

Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Multigrade engine oil, viscositySAE 10W/40 to 20W/50, to API SG

Cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ethylene glycol-based antifreeze with corrosion inhibitors

Manual transmission* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear oil, viscosity SAE 80 to API-GL4, or single-grade mineral-based

engine oil, viscosity SAE 20, 30 or 40 to API-SG

Automatic transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dexron ll type ATF

Final drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BMW-approved hypoid gear oil, viscosity SAE 90**

Brake and clutch hydraulic systems . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic brake fluid to SAE J 1703 or DOT 4

Power steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dexron ll type ATF

* E34 520i & 525i with air conditioning, E34 530i & 535i - Dexron II type ATF) ** Only available in bulk; refer to your BMW dealer

Capacities*

1•3

Engine oil

M10 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.0 litres

M20 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 litres

M30 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.8 litres

M40 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.0 litres

Cooling system

M10 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.0 litres

M20 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.5 litres

M30 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.0 litres

M40 engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.0 litres

Fuel tank

3-Series, E30

Saloon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 litres (early),

64 litres (later)

Estate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 litres (early),

70 litres (later)

5-Series

E28 (“old-shape”) . . . . . . . . . . . . . . . . . . . . . . . . 70 litres

E34 (“new-shape”) . . . . . . . . . . . . . . . . . . . . . . . 81 litres

Manual transmission

ZF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 litres

Getrag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 to 1.5 litres

Automatic transmission (refill)

3-speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 litres

4-speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litres

Final drive capacity (drain and refill)

3-Series, E30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.9 litres

5-Series, E28 (“old-shape”) . . . . . . . . . . . . . . . . . . 0.9 litres

5-Series, E34 (“new-shape”) . . . . . . . . . . . . . . . . . 1.7 litres

*All capacities approximate

Servicing Specifications

Maintenance schedule

The following maintenance intervals are based on the assumption that the vehicle owner will be doing the maintenance or service work, as opposed to having a dealer service department do the work. Although the time/mileage intervals are loosely based on factory recommendations, most have been shortened to ensure, for example, that such items as lubricants and fluids are checked/changed at intervals that promote maximum engine/driveline service life. Also, subject to the preference of the individual owner interested in keeping his or her vehicle in peak condition at all times, and with the vehicle’s ultimate resale in mind, many of the maintenance procedures may be performed more often than recommended in the following schedule. We encourage such owner initiative.

When the vehicle is new, it should be serviced initially by a factoryauthorised dealer service department, to protect the factory warranty. In many cases, the initial maintenance check is done at no cost to the owner (check with your dealer service department for more information).

1•4

Maintenance and servicing

Every 250 miles or weekly, whichever comes first

mm Check the engine oil level (Section 4) mm Check the engine coolant level (Section 4) mm Check the brake fluid level (Section 4) mm Check the clutch fluid level (Section 4) mm Check the washer fluid level (Section 4) mm Check the tyres and tyre pressures (Section 5)

Every 6000 miles or 6 months, whichever comes first

All items listed above, plus:

mm Change the engine oil and oil filter (Section 6) mm Check the power steering fluid level (Section 7) mm Check the tyres, and rotate if necessary (Section 9) mm Check the automatic transmission fluid level

(Section 8)

mm Check the underbonnet hoses (Section 10) mm Check/adjust the drivebelts (Section 11) mm Check engine idle speed and CO (Section 12)

Every 12 000 miles or 12 months, whichever comes first

All items listed above, plus:

mm Check/service the battery (Section 13) mm Check the spark plugs (Section 14) mm Check/renew the HT leads, distributor cap and

rotor (Section 15)

mm Check/top-up the manual transmission lubricant

(Section 16)

mm Check the differential oil level (Section 17) mm Check the valve clearances, and adjust if

necessary - does not apply to M40 engines (Section 18)

mm Check and lubricate the throttle linkage (Section 19) mm Renew the air filter (Section 20) mm Check the fuel system (Section 21) mm Inspect the cooling system (Section 22) mm Inspect the exhaust system (Section 23) mm Inspect the steering and suspension components

(Section 24)

mm Check the driveshaft gaiter(s) (Section 25) mm Inspect the brakes (Section 26) mm Inspect/renew the windscreen wiper blades

(Section 27)

Every 24 000 miles or 2 years, whichever comes first

All items listed above plus:

mm Change the automatic transmission fluid and filter

(Section 28)

mm Drain, flush and refill the cooling system (Section 29) mm Renew the spark plugs (Section 14) mm Check/renew the spark plug HT leads (Section 15) mm Renew the fuel filter (Section 30) mm Change the manual transmission lubricant (Section 31) mm Change the differential oil (Section 32) mm Check the evaporative emissions system, where

applicable (Section 33)

mm Reset the service indicator lights (Section 34) mm Renew brake fluid by bleeding (see Chapter 9) mm Check the handbrake operation (see Chapter 9)

Every 60 000 miles

mm Renew the timing belt (Section 35)

1•5

Underbonnet view (left-hand side) of a

UK model 318i (1988)

1 Radiator 2 Intake manifold 3 Idle control valve 4 Accelerator cable 5 Diagnostic/service indicator resetting

socket 6 Fuse/relay box 7 Brake hydraulic fluid reservoir 8 Airflow meter 9 Air cleaner unit

10 Radiator filler cap 11 Radiator top hose 12 Oil filter housing

Underbonnet view (right-hand side) of a

UK model 318i (1988)

1 Oil filler cap 2 Valve cover 3 Engine oil filler dipstick 4 Viscous cooling fan 5 Distributor cap cover 6 Bottom hose 7 Windscreen washer fluid reservoir 8 Ignition coil 9 Clutch hydraulic fluid reservoir

10 Battery

Maintenance and Servicing

1•6

Maintenance and Servicing

Front underbody view of a UK model 318i

(1988)

1 Radiator 2 Engine oil drain plug 3 Front suspension control arm (left-hand

side) 4 Front anti-roll bar 5 Clutch slave cylinder 6 Transmission 7 Exhaust downpipe 8 Front suspension control arm (right-hand

side)

Typical rear underside components

1 Exhaust system 2 Differential fill/check plug 3 Driveshaft boot 4 Fuel tank filler tube 5 Differential drain plug 6 Rear brake 7 Rear shock absorber

1 Introduction

This Chapter is designed to help the home mechanic maintain his or her vehicle with the goals of maximum performance, economy, safety and reliability in mind. Included is a master maintenance schedule, followed by procedures dealing specifically with each item on 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 various components. Servicing the vehicle, in accordance with the mileage/time maintenance schedule and the step-by-step procedures, will result in a planned maintenance programme that should produce a long and reliable service life. Keep in mind that it is a comprehensive plan, so maintaining some items but not others at specified intervals, will not produce the same results.

2 Routine maintenance

As you service the vehicle, you will discover that many of the procedures can - and should

- be grouped together, because of the nature of the particular procedure you’re performing, or because of the close proximity of two otherwise-unrelated components to one another. For example, if the vehicle is raised for chassis lubrication, you should inspect the exhaust, suspension, steering and fuel

systems while you’re under the vehicle. When the wheels are removed for other work, it makes good sense to check the brakes, since the wheels are already removed. Finally, let’s suppose you have to borrow a torque wrench. Even if you only need it to tighten the spark plugs, you might as well check the torque of as many critical nuts and bolts as time allows.

The first step in this maintenance programme is to prepare yourself before the actual work begins. Read through all the procedures you’re planning to do, then gather up all the parts and tools needed. If it looks like you might run into problems during a particular job, seek advice from a mechanic or an experienced do-it-yourselfer.

3 Engine “tune-up” -

general information

The term “tune-up” is used in this manual to represent a combination of individual operations rather than one specific procedure.

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.

More likely than not, however, there will be times when the engine is running poorly due to a 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, an engine tune-up will be needed outside of the regular maintenance intervals.

The first step in any tune-up or diagnostic procedure to help correct a poor-running engine is a cylinder compression check. A compression check (see Chapter 2B) will help determine the condition of internal engine components, and should be used as a guide for tune-up and repair procedures. If, for instance, a compression check indicates serious internal engine wear, a conventional tune-up will not improve the performance of the engine, and would be a waste of time and money. Because of its importance, the compression check should be done by someone with the right equipment, and the knowledge to use it properly.

The following procedures are those most often needed to bring a generally poorrunning engine back into a proper state of tune.

Minor tune-up

Check all engine-related fluids (Section 4)

Check all underbonnet hoses (Section 10)

Check and adjust the drivebelts (Sec-

tion 11)

Clean, inspect and test the battery (Sec-

tion 13)

Renew the spark plugs (Section 14)

Inspect the spark plug HT leads, distributor

cap and rotor (Section 15)

Check the air filter (Section 20)

Check the cooling system (Section 22)

Major tune-up

All items listed under minor tune-up, plus . . .

Check the ignition system (see Chapter 5)

Check the charging system (see Chapter 5)

Check the fuel system (see Chapter 4)

Renew the spark plug HT leads, distributor

cap and rotor (Section 15)

1•7

Routine Maintenance

Weekly checks

4 Fluid level checks

Note: The following are fluid level checks to be done on a 250-mile or weekly basis. Additional fluid level checks can be found in specific maintenance procedures which follow. Regardless of intervals, be alert to fluid leaks under the vehicle, which would indicate a fault to be corrected immediately.

1 Fluids are an essential part of the lubrication, cooling, brake and windscreen washer systems. Because the fluids gradually become depleted and/or contaminated during normal operation of the vehicle, they must be periodically replenished. See “Lubricants and fluids” at the beginning of this Chapter before adding fluid to any of the following components. Note: The vehicle must be on

level ground when any fluid levels are checked.

Engine oil

2 Engine oil is checked with a dipstick, which is located on the side of the engine (refer to the underbonnet illustrations in this Chapter for dipstick location). The dipstick extends through a metal tube down into the sump. 3 The engine oil should be checked before the vehicle has been driven, or at least 15 minutes after the engine has been shut off.

4 Pull the dipstick out of the tube, and wipe all of the oil away from the end with a clean rag or paper towel. Insert the clean dipstick all the way back into the tube, and pull it out again. Note the oil at the end of the dipstick. At its highest point, the oil should be between

the two notches or marks (see illustration). 5 It takes one litre of oil to raise the level from the lower mark to the upper mark on the dipstick. Do not allow the level to drop below the lower mark, or oil starvation may cause

4.4 The oil level should be kept between the two marks, preferably at or near the

upper one - if it isn’t, add enough oil to

bring the level to the upper mark

If the oil is checked immediately after driving the vehicle, some of the oil will

remain in the upper part of the engine, resulting in an inaccurate reading on the dipstick.

engine damage. Conversely, overfilling the engine (adding oil above the upper mark) may cause oil-fouled spark plugs, oil leaks, or oil seal failures. 6 To add oil, remove the filler cap located on the valve cover (see illustrations). After adding oil, wait a few minutes to allow the level to stabilise, then pull the dipstick out and check the level again. Add more oil if required. Refit the filler cap, tightening it by hand only. 7 Checking the oil level is an important preventive maintenance step. A consistently low oil level indicates oil leakage through damaged seals or defective gaskets, or oil burning (internal leakage past worn rings or valve guides). The condition of the oil should also be noted. If the oil looks milky in colour or has water droplets in it, the cylinder head gasket may be blown, or the head or block may be cracked. The engine should be repaired immediately. Whenever you check the oil level, slide your thumb and index finger up the dipstick before wiping off the oil. If you see small dirt or metal particles clinging to the dipstick, the oil should be changed (see Section 6).

Engine coolant

Warning: Do not allow antifreeze to come in contact with your skin, or with the vehicle

paintwork. Rinse off spills immediately with plenty of water. Antifreeze is highly toxic if ingested. Never leave antifreeze lying around in an open container, or in puddles on the floor; children and pets are attracted by its sweet smell, and may drink it. Check with local authorities about disposing of used antifreeze. Local collection centres may exist, to see that antifreeze is disposed of safely.

8 All vehicles covered by this manual are equipped with a pressurised coolant recovery system. On most models, a white plastic expansion tank (or coolant reservoir) located in the engine compartment is connected by a hose to the radiator. As the engine heats up during operation, the expanding coolant fills the tank. As the engine cools, the coolant is automatically drawn back into the cooling system, to maintain the correct level.

9 The coolant level in the reservoir (see illustrations) should be checked regularly.

Add a 40%/60% mixture of ethylene glycolbased antifreeze to water (see illustration).

Warning: Do not remove the expansion tank cap or radiator cap to check the coolant level,

unless the engine is completely cold! The level in the reservoir varies with the temperature of the engine. When the engine is cold, the coolant level should be

above the LOW mark on the reservoir. Once the engine has warmed up, the level should be at or near the FULL mark. If it isn’t, allow the engine to cool, then remove the cap from the reservoir.

10 Drive the vehicle and recheck the coolant level. If only a small amount of coolant is required to bring the system up to the proper level, plain water can be used. However, repeated additions of water will dilute the antifreeze. In order to maintain the proper ratio of antifreeze and water, always top-up the coolant level with the correct mixture. 11 If the coolant level drops consistently, there must be a leak in the system. Inspect the radiator, hoses, filler cap, drain plugs and water pump (see Section 29). If no leaks are noted, have the expansion tank cap or radiator cap pressure-tested by a BMW dealer. 12 If you have to remove the cap, wait until the engine has cooled completely, then wrap a thick cloth around the cap and turn it to the first stop. If coolant or steam escapes, let the engine cool down longer, then remove the cap. 13 Check the condition of the coolant as well. It should be relatively clear. If it’s brown or rust-coloured, the system should be drained, flushed and refilled. Even if the coolant appears to be normal, the corrosion

1•8

4.9d Adding antifreeze mixture4.9c On some 5-Series models, the

expansion tank (coolant reservoir) is

located on the bulkhead

4.9b On other models, the expansion tank

(coolant reservoir) is located on the side of

the engine compartment - remove the cap

to add coolant

4.9a On some models, the expansion tank (coolant reservoir) is mounted on the

radiator - make sure the level is kept at or

near the FULL mark (arrowed)

4.6b Topping-up the engine oil4.6a The threaded oil filler cap is located

in the valve cover - always make sure the

area around the opening is clean before

unscrewing the cap

Weekly Checks

inhibitors wear out, so it must be renewed at the specified intervals.

Brake and clutch fluid

Warning: Brake fluid can harm your eyes and damage painted surfaces, so use extreme caution

when handling or pouring it. Do not use brake fluid that has been standing open or is more than one year old. Brake fluid absorbs moisture from the air, which can cause a dangerous loss of brake effectiveness. Use only the specified type of brake fluid. Mixing different types (such as DOT 3 or 4 and DOT 5) can cause brake failure.

14 The brake master cylinder is mounted at the left rear corner of the engine compartment. The clutch fluid reservoir (manual transmission models) is mounted on the right-hand side. 15 To check the clutch fluid level, observe the level through the translucent reservoir. The level should be at or near the step moulded into the reservoir. If the level is low, remove the reservoir cap to add the specified fluid (see illustration). 16 The brake fluid level is checked by looking through the plastic reservoir mounted on the master cylinder (see illustration). The fluid level should be between the MAX and MIN lines on the reservoir. If the fluid level is low, first wipe the top of the reservoir and the cap with a clean rag, to prevent contamination of the system as the cap is unscrewed. Top-up with the recommended brake fluid, but do not overfill. 17 While the reservoir cap is off, check the master cylinder reservoir for contamination. If rust deposits, dirt particles or water droplets are present, the system should be drained and refilled. 18 After filling the reservoir to the proper level, make sure the cap is seated correctly, to prevent fluid leakage and/or contamination. 19 The fluid level in the master cylinder will drop slightly as the disc brake pads wear. There is no need to top up to compensate for this fall provided that the level stays above the MIN line; the level will rise again when new pads are fitted. A very low level may indicate

worn brake pads. Check for wear (see Section 26). 20 If the brake fluid level drops consistently, check the entire system for leaks immediately. Examine all brake lines, hoses and connections, along with the calipers, wheel cylinders and master cylinder (see Section 26). 21 When checking the fluid level, if you discover one or both reservoirs empty or nearly empty, the brake or clutch hydraulic system should be checked for leaks and bled (see Chapters 8 and 9).

Windscreen washer fluid

22 Fluid for the windscreen washer system is stored in a plastic reservoir in the engine compartment (see illustration). 23 In milder climates, plain water can be used in the reservoir, but it should be kept no more than two-thirds full, to allow for expansion if the water freezes. In colder climates, use windscreen washer system antifreeze, available at any car accessory shop, to lower the freezing point of the fluid. This comes in concentrated or pre-mixed form. If you purchase concentrated antifreeze, mix the antifreeze with water in accordance with the manufacturer’s directions on the container.

Caution: Do not use cooling system antifreeze - it will damage the vehicle’s paint.

5 Tyre and tyre pressure

checks

1 Periodic inspection of the tyres may save you the inconvenience of being stranded with a flat tyre. It can also provide you with vital information regarding possible problems in the steering and suspension systems before major damage occurs. 2 Tyres are equipped with bands that will appear when tread depth reaches 1.6 mm, at which time the tyres can be considered worn out. This represents the legal minimum tread depth; most authorities recommend renewing any tyre on which the tread depth is 2 mm or less. Tread wear can be monitored with a simple, inexpensive device known as a tread depth indicator (see illustration).

3 Note any abnormal tyre wear (see illustration overleaf). Tread pattern irregular-

ities such as cupping, flat spots and more wear on one side than the other are indications of front end alignment and/or wheel balance problems. If any of these conditions are noted, take the vehicle to a tyre specialist to correct the problem. 4 Look closely for cuts, punctures and embedded nails or tacks. Sometimes, after a nail has embedded itself in the tread, a tyre will hold air pressure for a short time, or may

1•9

4.22 The windscreen washer fluid reservoir is located in the right front corner of the

engine compartment on most models

4.16 The brake fluid level should be kept above the MIN mark on the translucent

reservoir - unscrew the cap to add fluid

4.15 Adding hydraulic fluid to the clutch fluid reservoir

5.4a If a slow puncture is suspected,

check the valve core first to make sure it’s

tight

5.2 Use a tyre tread depth indicator to

monitor tyre wear - they are available at

car accessory shops and service stations,

and cost very little

Weekly Checks

leak down very slowly. If a slow puncture persists, check the valve stem core to make sure it is tight (see illustration). Examine the tread for an object that may have embedded itself in the tyre, or for a previous repair that may have begun to leak. If a puncture is suspected, it can be easily verified by spraying a solution of soapy water onto the puncture (see illustration). The soapy solution will bubble if there is a leak. Unless the puncture is unusually large, a tyre specialist can usually repair the tyre. 5 Carefully inspect the inner sidewall of each tyre for evidence of brake fluid leakage. If you see any, inspect the brakes immediately. 6 Correct air pressure adds miles to the life span of the tyres, improves fuel economy, and enhances overall ride quality. A tyre pressure gauge is essential.

7 Always check the tyre pressures when the tyres are cold (ie before driving the vehicle).

Checking the pressures when the tyres are warm, or hot, will result in higher readings, due to heat expansion. On no account should air be let out of the tyres in this case, or the tyres will effectively be under-inflated when cold. 8 Unscrew the valve cap protruding from the wheel or hubcap, and push the gauge firmly onto the valve stem (see illustration). Note the reading on the gauge, and compare the

figure to the recommended tyre pressures shown in the Specifications listed at the beginning of this Chapter. Be sure to refit the valve cap to keep dirt and moisture out of the valve stem mechanism. Check all four tyres and, if necessary, add enough air to bring them to the recommended pressure. 9 Don’t forget to keep the spare tyre inflated to the specified pressure.

1•10

5.8 To extend the life of the tyres, check

the air pressure at least once a week with

an accurate gauge (don’t forget the spare!)

5.4b If the valve core is tight, raise the

vehicle, and spray a soapy water solution

onto the tread as the tyre is turned slowly -

leaks will cause small bubbles to appear

Tyre tread wear patterns

Shoulder 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!

Centre Wear

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 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.

Uneven Wear

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.

Weekly Checks

Keep an accurate gauge in the glove compartment. The pressure gauges attached to

the nozzles of air hoses at service stations are often inaccurate.

Every 6000 miles or 6 months, whichever comes first

1•11

6.17a Unscrew the bolt . . .

Every 6000 miles

6 Engine oil and filter change

Warning: Prolonged skin contact with used engine oil is

hazardous. Use a barrier cream and wear gloves during this procedure. Change out of oil-soaked clothing immediately.

1 Make sure that you have all the necessary tools before you begin this procedure (see illustration). You should also have plenty of rags or newspapers handy for mopping up oil spills

2 Start the engine and allow it to reach normal operating temperature - oil and sludge will flow more easily when warm. If new oil, a filter or tools are needed, use the vehicle to go and get them, thus warming up the engine oil at the same time. 3 Park on a level surface, and switch off the engine when it’s warmed up. Remove the oil filler cap from the valve cover. 4 Access to the oil drain plug and filter will be improved if the vehicle can be lifted on a hoist, driven onto ramps, or supported by axle stands.

Warning: DO NOT work under a vehicle supported only by a hydraulic or scissors-type jack always use axle stands!

5 If you haven’t changed the oil on this vehicle before, get under it, and locate the drain plug and the oil filter. Note that on some engines, the oil filter is located on the top lefthand side of the engine. The exhaust components will be hot as you work, so note how they are routed to avoid touching them. 6 Being careful not to touch the hot exhaust components, position a drain pan under the plug in the bottom of the engine. 7 Clean the area around the plug, then remove the plug (see illustration). It’s a good idea to wear a rubber glove while unscrewing the plug the final few turns, to avoid being scalded by hot oil. Hold the drain plug against

the threads as you unscrew it, then pull it away from the drain hole suddenly. This will place your arm out of the way of the hot oil, as well as reducing the chances of dropping the drain plug into the drain pan. 8 It may be necessary to move the drain pan slightly as oil flow slows to a trickle. Inspect the old oil for the presence of metal particles, which could give early warning of engine wear. 9 After all the oil has drained, wipe off the drain plug with a clean rag. Any small metal particles clinging to the plug would immediately contaminate the new oil. 10 Refit the plug and tighten it securely. Use a new washer if necessary. 11 Move the drain pan into position under the oil filter.

Canister-type oil filter

12 Loosen the spin-off type oil filter by turning it anti-clockwise with a filter spanner. Any standard filter spanner will work. 13 Sometimes the spin-off type oil filter is screwed on so tightly that it can’t be easily loosened. If it is, punch a metal bar or long screwdriver directly through it, and use it as a T-bar to turn the filter. Be prepared for oil to spurt out of the canister as it’s punctured. 14 Once the filter is loose, use your hands to unscrew it from the block. Just as the filter is detached from the block, immediately tilt the open end up to prevent oil inside the filter from spilling out. 15 Using a clean rag, wipe off the mounting surface on the block. Also, make sure that none of the old sealing ring remains stuck to the mounting surface. It can be removed with a scraper if necessary. 16 Compare the old filter with the new one, to make sure they are the same type. Smear some engine oil on the rubber sealing ring of the new filter, and screw it into place (see illustration). Overtightening the filter will damage the sealing ring, so don’t use a filter spanner. Most filter manufacturers recommend tightening the filter by hand only. Normally, they should be tightened threequarters of a turn after the sealing ring contacts the block, but be sure to follow the directions on the filter or container.

6.1 These tools are required when changing the engine oil and filter

1 Drain pan - It should be fairly shallow in

depth, but wide enough to prevent spills

2 Rubber gloves - When removing the drain

plug and filter, you will get oil on your hands (the gloves will prevent burns)

3 Socket bar - Sometimes the oil drain plug

is tight, and a long bar is needed to loosen it. The correct-size ring spanner may work just as well

4 Socket - To be used with the bar or a

ratchet (must be the correct size to fit the drain plug - six-point preferred)

5 Filter spanner - This is a metal band-type

spanner, which requires clearance around the filter to be effective. This tool is not required on all engines.

6 Filter spanner - This type fits on the bottom

of the filter and can be turned with a ratchet or breaker bar (different-size spanners are available for different types of filters) This tool is not required on all engines.

6.7 Using a ring spanner to remove the oil drain plug

6.16 Lubricate the oil filter sealing ring

with clean engine oil before refitting the

filter on the engine

Frequent oil changes are the most important preventive maintenance procedures that

can be done by the home mechanic. As engine oil ages, it becomes diluted and contaminated, which leads to premature engine wear.

Cartridge-type oil filter

17 Some models are equipped with a cartridge-type oil filter. Unscrew the bolt, remove the cover, and lift the filter out (see

illustrations). 18 Compare the new cartridge with the old

one, to make sure they are the same type, then lower it into the housing. 19 Using a clean rag, wipe off the mounting surface of the housing and cover. If necessary, renew the rubber O-ring (see illustration). Smear some clean oil on the O-ring and refit the cover and bolt. Tighten the bolt securely.

All models

20 Remove all tools and materials from under the vehicle, being careful not to spill the oil from the drain pan, then lower the vehicle. 21 Add new oil to the engine through the oil filler cap in the valve cover. Use a funnel to prevent oil from spilling onto the top of the engine. Pour the specified quantity of fresh oil into the engine. Wait a few minutes to allow the oil to drain into the sump, then check the level on the dipstick (see Section 4 if necessary). If the oil level is correct, refit the filler cap. 22 Start the engine and run it for about a minute. The oil pressure warning light may take a few seconds to go out while the new filter fills with oil; don’t rev the engine while the light is on. While the engine is running, look under the vehicle, and check for leaks at the sump drain plug and around the oil filter. If

either one is leaking, stop the engine and tighten the plug or filter slightly. 23 Wait a few minutes, then recheck the level on the dipstick. Add oil as necessary. 24 During the first few days after an oil change, make it a point to check frequently for leaks and proper oil level. 25 The old oil drained from the engine cannot be re-used in its present state, and should be discarded. Oil reclamation centres and some service stations will accept the oil, which can be recycled. After the oil has cooled, it can be transferred into a container for transport to a disposal site.

7 Power steering fluid level

check

1 Check the power steering fluid level periodically to avoid steering system problems, such as damage to the pump. Proceed as follows.

Caution: Do not hold the steering wheel against either stop (full-left or full-right lock) for more than five seconds. If you do, the power steering pump could be damaged.

2 On some models, the power steering fluid reservoir is located on the left side of the engine compartment, and has a twist-off cap with an integral fluid level dipstick (see illustration). Other models use a hydraulic power steering and brake servo system which combines the fluid in one reservoir, located at the right rear corner of the engine compartment. 3 Park the vehicle on level ground, and apply the handbrake. 4 On models with a fluid dipstick, run the engine until it has reached normal operating temperature. With the engine at idle, turn the steering wheel back and forth several times to get any air out of the steering system. Switch off the engine, remove the cap by turning it anti-clockwise, wipe the dipstick clean, and refit the cap. Remove the cap again, and note the fluid level. It must be between the two lines (see illustration). 5 On hydraulic servo models, pump the brake pedal about ten times or until the pedal is firm. Remove the nut, lift the cap off, and make sure the fluid is within 6.0 mm of the top of the reservoir. 6 Add small amounts of fluid until the level is correct (see illustration).

1•12

7.6 Adding fluid to the power steering reservoir

7.4 The power steering fluid level should be kept between the two arrows near the

upper step on the dipstick

7.2 The power steering fluid reservoir

(arrowed) is located on the left side of the

engine compartment

6.19 Renewing the rubber O-ring in the cover

6.17c . . . and lift out the cartridge

Every 6000 miles

6.17b . . . remove the cover . . .

Note: It is antisocial and illegal to dump oil down the drain. To find the location of your local oil recycling bank, call this number free.

Caution: Do not overfill the reservoir. If too much fluid is added, remove the excess with a clean syringe. Refit the cap.

7 If frequent topping-up is needed, check the power steering hoses and connections for leaks and wear (see Section 10). 8 Check the condition and tension of the drivebelt (see Section 11).

8 Automatic transmission fluid

level check

Caution: The use of transmission fluid other than the type listed in this Chapter’s Specifications could result in transmission malfunctions or failure.

1 The automatic transmission fluid should be carefully maintained. Low fluid level can lead to slipping or loss of drive, while overfilling can cause foaming and loss of fluid. Either condition can cause transmission damage. 2 Since transmission fluid expands as it heats up, the fluid level should only be checked when the transmission is warm (at normal operating temperature). If the vehicle has just been driven over 20 miles (32 km), the transmission can be considered warm. You can also check the fluid level when the transmission is cold. If the vehicle has not been driven for over five hours and the fluid is about room temperature (20°C), the transmission is cold. However, the fluid level is normally checked with the transmission warm, to ensure accurate results.

Caution: If the vehicle has just been driven for a long time at high speed or in city traffic, in hot

weather, or if it has been pulling a trailer, an accurate fluid level reading cannot be obtained. Allow the transmission to cool down for about 30 minutes.

3 Immediately after driving the vehicle, park it on a level surface, apply the handbrake and start the engine. While the engine is idling, depress the brake pedal and move the

selector lever through all the gear ranges, beginning and ending in Park. 4 The automatic transmission dipstick tube is located in the left rear corner of the engine compartment. 5 With the engine still idling, pull the dipstick out of the tube (see illustration), wipe it off with a clean rag, push it all the way back into the tube and withdraw it again, then note the fluid level.

6 The level should be between the two marks (see illustration). If the level is low, add the

specified automatic transmission fluid through the dipstick tube - use a clean funnel, preferably equipped with a fine mesh filter, to prevent spills.

Caution: Be careful not to introduce dirt into the transmission when topping up.

7 Add just enough of the recommended fluid to fill the transmission to the proper level. It takes about half a litre to raise the level from the low mark to the high mark when the fluid is hot, so add the fluid a little at a time, and keep checking the level until it’s correct. 8 The condition of the fluid should also be checked along with the level. If the fluid is black or a dark reddish-brown colour, or if it smells burned, it should be changed (see Section 28). If you are in doubt about its condition, purchase some new fluid, and compare the two for colour and smell.

9 Tyre rotation

1 The tyres can be rotated at the specified intervals, or whenever uneven wear is noticed. However, bear in mind that if rotation succeeds in making all the tyres wear evenly, you will eventually have to renew all four at once. Since the vehicle will be raised and the wheels removed anyway, check the brakes also (see Section 26). Note: Even if you don’t

rotate the tyres, at least check the wheel bolt tightness.

2 It is recommended that the tyres be rotated

in a specific pattern (see illustration) so that their direction of rotation remains the same.

3 Refer to the information in “Jacking and towing” at the front of this manual for the

proper procedure to follow when raising the vehicle and changing a tyre. 4 The vehicle must be raised on a hoist or supported on axle stands to get all four tyres off the ground. Make sure the vehicle is safely supported! 5 After the rotation procedure is finished, check and adjust the tyre pressures as necessary, and be sure to check the wheel bolt tightness.

10 Underbonnet hose check

and renewal

Warning: Renewal of air conditioning hoses must be left to a dealer service department or

air conditioning specialist having the equipment to depressurise the system safely. Never disconnect air conditioning hoses or components until the system has been depressurised.

General

1 High temperatures under the bonnet can cause deterioration of the rubber and plastic hoses used for various systems. Periodic inspection should be made for cracks, loose clamps, material hardening, and leaks. 2 Information specific to the cooling system can be found in Section 22, while the braking system is covered in Section 26. 3 Most (but not all) hoses are secured with clamps. Where clamps are used, check to be sure they haven’t lost their tension, allowing the hose to leak. If clamps aren’t used, make sure the hose has not expanded and/or hardened where it slips over the fitting, allowing it to leak.

Vacuum hoses

4 It’s quite common for vacuum hoses, especially those in the emissions system, to be colour-coded or identified by coloured

1•13

9.2 The tyre rotation pattern for these models

8.6 With the fluid hot, the level should be kept between the two dipstick notches,

preferably near the upper one

8.5 The automatic transmission fluid

dipstick (arrowed) is located near the

bulkhead on the left side of the engine

compartment

Every 6000 miles

stripes moulded into them. Various systems require hoses with different wall thicknesses, collapse resistance and temperature resistance. When fitting new hoses, be sure the new ones are made of the same material. 5 Often the only effective way to check a hose is to remove it completely from the vehicle. If more than one hose is removed, be sure to label the hoses and fittings to ensure correct refitting. 6 When checking vacuum hoses, be sure to include any plastic T-fittings in the check. Inspect the connections for cracks which could cause leakage. 7 A small piece of vacuum hose can be used as a stethoscope to detect vacuum leaks. Hold one end of the hose to your ear and probe around vacuum hoses and fittings, listening for the “hissing” sound characteristic of a vacuum leak.

Warning: When probing with the vacuum hose stethoscope, be careful not to touch moving engine components such as the drivebelt, cooling fan, etc.

Fuel hoses

Warning: There are certain precautions which must be taken when servicing or inspecting fuel

system components. Work in a well-ventilated area, and do not allow open flames (cigarettes, appliance pilot lights, etc.) or bare light bulbs near the work area. Mop up any spills immediately, and do not store fuel-soaked rags where they could ignite. If you spill any fuel on your skin, rinse it off immediately with soap and water. When you perform any kind of work on the fuel system, wear safety glasses, and have a fire extinguisher on hand.

8 The fuel hoses are usually under pressure, so if any fuel hoses are to be disconnected, be prepared to catch spilled fuel.

Warning: On vehicles equipped

with fuel injection, you must

depressurise the fuel system

before servicing the fuel hoses.

Refer to Chapter 4 for details.

9 Check all rubber fuel hoses for deterioration and chafing. Check especially for cracks in areas where the hose bends, and just before connectors, such as where a hose attaches to the fuel pump or fuel filter, for example. 10 Only high-quality fuel hose should be used. Never, under any circumstances, use unreinforced vacuum hose, clear plastic tubing or water hose for fuel hoses. 11 Band-type clamps are commonly used on fuel hoses. These clamps often lose their tension over a period of time, and can be “sprung” during removal. Renew all band-type clamps with screw clamps whenever a hose is renewed.

Metal lines

12 Sections of metal line are often used between the fuel pump and fuel injection system. Check carefully to make sure the line isn’t bent, crimped or cracked. 13 If a section of metal line must be renewed, use seamless steel tubing only, since copper and aluminium tubing do not have the strength necessary to withstand the vibration caused by the engine. 14 Check the metal brake lines where they enter the master cylinder and brake proportioning or ABS unit (if used) for cracks in the lines and loose fittings. Any sign of brake fluid leakage calls for an immediate thorough inspection of the braking system.

Power steering hoses

15 Check the power steering hoses for leaks, loose connections and worn clamps. Tighten loose connections. Worn clamps or leaky hoses should be renewed.

11 Drivebelt check, adjustment

and renewal

Check

1 The drivebelts, sometimes called V-belts or simply “fan” belts, are located at the front of the engine, and play an important role in the overall operation of the vehicle and its

components. Due to their function and material make-up, the belts are prone to failure after a period of time, and should be inspected and adjusted periodically to prevent major engine damage. 2 The number of belts used on a particular vehicle depends on the accessories fitted. Drivebelts are used to turn the alternator, power steering pump, water pump, and air conditioning compressor. Depending on the pulley arrangement, a single belt may be used to drive more than one of these components. 3 With the engine switched off, open the bonnet and locate the various belts at the front of the engine. Using your fingers (and a torch, if necessary), move along the belts, checking for cracks and separation of the belt plies. Also check for fraying and glazing, which gives the belt a shiny appearance (see illustration). Both sides of the belts should be inspected, which means you will have to twist each belt to check the underside. 4 The tension of each belt is checked by pushing firmly with your thumb and seeing how much the belt moves (deflects). Measure the deflection with a ruler (see illustration). A good rule of thumb is that the belt should deflect 6 mm if the distance from pulley centre-to-pulley centre is between 180 and 280 mm. The belt should deflect 13 mm if the distance from pulley centre-to-pulley centre is between 300 and 400 mm.

Adjustment

5 If it is necessary to adjust the belt tension, either to make the belt tighter or looser, it is done by moving a belt-driven accessory on its bracket. (When the same belt drives more than one accessory, normally only one accessory is moved when making adjustment.) 6 For each component, there will be an adjusting bolt and a pivot bolt. Both bolts must be loosened slightly to enable you to move the component. On some components, the drivebelt tension can be adjusted by turning an adjusting bolt after loosening the lockbolt (see illustration). 7 After the two bolts have been loosened,

1•14

11.6 Loosen the nut on the other end of the adjuster bolt (arrowed) and turn the

bolt to increase or decrease tension on the

drivebelt

11.4 Measuring drivebelt deflection with a straightedge and ruler

11.3 Here are some of the more common problems associated with drivebelts

(check the belts very carefully to prevent

an untimely breakdown)

Every 6000 miles

move the component away from the engine to tighten the belt, or towards the engine to loosen the belt. Hold the accessory in position, and check the belt tension. If it is correct, tighten the two bolts until just tight, then recheck the tension. If the tension is still correct, tighten the bolts. 8 It will often be necessary to use some sort of lever to move the accessory while the belt is adjusted. If this must be done to gain the proper leverage, be very careful not to damage the component being moved, or the part being prised against.

Renewal

9 To renew a belt, follow the instructions above for adjustment, but remove the belt from the pulleys. 10 In some cases, you will have to remove more than one belt, because of their arrangement on the front of the engine. Because of this, and the fact that belts will tend to fail at the same time, it is wise to renew all belts together. Mark each belt and its appropriate pulley groove, so all renewed belts can be fitted in their proper positions. 11 It is a good idea to take the old belts with you when buying new ones, in order to make a direct comparison for length, width and design. 12 Recheck the tension of new belts after a few hundred miles.

12 Engine idle speed and CO

level check and adjustment

Note: The engine should be at normal operating temperature, with correct ignition timing and valve clearances (where adjustable). The air filter should be in good condition, and all electrical components (including the air conditioning, where fitted) should be switched off.

Carburettor

1 Connect a tachometer and exhaust gas analyser (CO meter) to the engine.

2 Start the engine and allow it to idle. 3 Check that the idle speed is as given in the

Specifications. Adjustment of the idle speed is only possible on the 2B4 carburettor. Turn the carburettor idle speed adjustment screw until the engine idles at the correct speed (see

illustration). 4 If the idle speed is low on the 2BE

carburettor, and all wiring to the carburettor is in good condition, it is possible to connect a resistance into the control circuit. This should be carried out by your BMW dealer. 5 Check that the CO reading is as given in the Specifications. If not, turn the carburettor idle mixture adjustment screw until the mixture is correct (see illustration).

L-Jetronic

6 Connect a tachometer and CO meter to the engine. BMW technicians use a special CO tester with a probe connected into the exhaust manifold, but the normal type of tester which locates in the exhaust tailpipe can be used instead. Note however that on models with a catalytic converter, meaningful CO readings will not be obtained at the tailpipe.

7 Start the engine and allow it to idle. 8 Check that the idle speed is as given in

Specifications. If not, remove the tamperproof cap from the throttle housing, and turn the idle adjustment screw until the speed is correct. 9 Check that the CO reading is as given in the Specifications. The mixture control screw is located on the airflow meter, and a special

tool (BMW number 13 1 060) may be required to make the adjustment.

Motronic

10 Connect a tachometer and CO meter to the engine. BMW technicians use a special CO tester with a probe connected into the exhaust manifold, but the normal type of tester which locates in the exhaust tailpipe may be used instead. Note however that on models with a catalytic converter, meaningful CO readings will not be obtained at the tailpipe. 11 It is not possible to adjust the idle speed manually, as the idle air stabiliser valve is activated by the electronic control unit. If the idle speed is not within the specified range with the engine at normal operating temperature, check for a leak in the air inlet system, and also check the operation of the idle air stabiliser valve (see Chapter 4). 12 Check that the CO reading is as given in the Specifications. If adjustment is required, prise out the tamperproof plug from the airflow meter, and turn the adjustment screw to set the CO content (on some models, an Allen key will be required). Fit a new tamperproof plug on completion (see illustrations).

1•15

12.12a Removing the tamperproof plug from the airflow meter

12.5 Mixture adjustment screw (2) on the 2B4 carburettor

12.3 Idle speed adjustment screw on the 2B4 carburettor (shown with the

carburettor removed)

12.12b Adjusting the CO on the Motronic system

Every 6000 miles

13 Battery check, maintenance

and charging

Check and maintenance

Warning: Certain precautions must be followed when checking and servicing the battery.

Hydrogen gas, which is highly flammable, is always present in the battery cells, so keep lighted tobacco and all other flames and sparks away from it. The electrolyte inside the battery is actually dilute sulphuric acid, which will cause injury if splashed on your skin or in your

eyes. It will also ruin clothes and painted surfaces. When disconnecting the battery cables, always detach the negative cable first, and connect it last!

1 Battery maintenance is an important procedure, which will help ensure that you are not stranded because of a dead battery. Several tools are required for this procedure

(see illustration). 2 Before servicing the battery, always switch

off the engine and all accessories, and disconnect the cable from the negative terminal of the battery.

Caution: If the radio in your vehicle is equipped with an anti-

theft system, make sure you have the correct activation code before disconnecting the battery.

Note: If, after connecting the battery, the wrong language appears on the instrument panel display, refer to page 0-7 for the language resetting procedure.

3 A low-maintenance battery is standard equipment. The cell caps can be removed and distilled water can be added, if necessary. Later models may be fitted with a “maintenance-free” battery, which is sealed. 4 Remove the caps and check the electrolyte level in each of the battery cells. It must be above the plates. There’s usually a split-ring indicator in each cell to indicate the correct level. If the level is low, add distilled water only, then refit the cell caps.

Caution: Overfilling the cells may cause electrolyte to spill over during periods of heavy charging, causing corrosion and damage to nearby components.

5 If the positive terminal and cable clamp on your vehicle’s battery is equipped with a rubber protector, make sure that it’s not torn or damaged. It should completely cover the terminal. 6 The external condition of the battery should be checked periodically. Look for damage such as a cracked case. 7 Check the tightness of the battery cable clamps to ensure good electrical connections. Check the entire length of each cable, looking for cracked or abraded insulation and frayed conductors. 8 If corrosion (visible as white, fluffy deposits) is evident, remove the cables from the terminals, clean them with a battery brush, and reconnect them (see illustrations). Corrosion can be kept to a minimum by fitting specially treated washers available at car accessory shops, or by applying a layer of petroleum jelly or suitable grease to the

Every 12 000 miles or 12 months, whichever comes first

1•16

13.8d When cleaning the cable clamps, all corrosion must be removed (the inside of

the clamp is tapered to match the taper on

the post, so don’t remove too much

material)

13.8c Regardless of the type of tool used

on the battery posts, a clean, shiny surface

should be the result

13.1 Tools and materials required for battery maintenance

1 Face shield/safety goggles - When

removing corrosion with a brush, the acidic particles can easily fly up into your eyes

2 Baking soda - A solution of baking soda and

water can be used to neutralise corrosion

3 Petroleum jelly - A layer of this on the

battery posts will help prevent corrosion

4 Battery post/cable cleaner - This wire-

brush cleaning tool will remove all traces of corrosion from the battery posts and cable clamps

5 Treated felt washers - Placing one of

these on each post, directly under the cable clamps, will help prevent corrosion

6 Puller - Sometimes the cable clamps are

very difficult to pull off the posts, even after the nut/bolt has been completely loosened. This tool pulls the clamp straight up and off the post without damage

7 Battery post/cable cleaner - Here is

another cleaning tool which is a slightly different version of No 4 above, but it does the same thing

8 Rubber gloves - Another safety item to

consider when servicing the battery; remember that’s acid inside the battery!

13.8b Removing a cable from the battery post with a spanner - sometimes special

battery pliers are required for this

procedure, if corrosion has caused

deterioration of the nut (always remove the

earth cable first, and connect it last!)

13.8a Battery terminal corrosion usually appears as light, fluffy powder

Every 12 000 miles

terminals and cable clamps after they are assembled. 9 Make sure that the battery carrier is in good condition, and that the hold-down clamp bolt is tight. If the battery is removed (see Chapter 5 for the removal and refitting procedure), make sure that no parts remain in the bottom of the carrier when it’s refitted. When refitting the hold-down clamp, don’t overtighten the bolt. 10 Corrosion on the carrier, battery case and surrounding areas can be removed with a solution of water and baking soda. Apply the mixture with a small brush, let it work, then rinse it off with plenty of clean water. 11 Any metal parts of the vehicle damaged by corrosion should be coated with a zincbased primer, then painted. 12 Additional information on the battery and jump starting can be found in Chapter 5 and the front of this manual.

Charging

Note: The manufacturer recommends the battery be removed from the vehicle for charging, because the gas which escapes during this procedure can damage the paint or interior, depending on the location of the battery. Fast charging with the battery cables connected can result in damage to the electrical system.

13 Remove all of the cell caps (if applicable), and cover the holes with a clean cloth to prevent spattering electrolyte. Disconnect the

battery negative cable, and connect the battery charger leads to the battery posts (positive to positive, negative to negative), then plug in the charger. Make sure it is set at 12 volts if it has a selector switch.

Caution: If the radio in your vehicle is equipped with an antitheft system, make sure you have

the correct activation code before disconnecting the battery. Note: If, after connecting the battery, the wrong language appears on the instrument panel display, refer to page 0-7 for the language resetting procedure.

14 If you’re using a charger with a rate higher than two amps, check the battery regularly during charging to make sure it doesn’t overheat. If you’re using a trickle charger, you can safely let the battery charge overnight after you’ve checked it regularly for the first couple of hours. Where a maintenance-free battery is fitted, special precautions may be necessary when charging it (for example, the charge rate is normally very low). There may be a warning label on the battery, but if not, consult a BMW dealer or auto-electrician. 15 If the battery has removable cell caps, measure the specific gravity with a hydrometer every hour during the last few hours of the charging cycle. Hydrometers are available inexpensively from car accessory shops - follow the instructions that come with the hydrometer. Consider the battery charged when there’s no change in the specific gravity reading for two hours, and the electrolyte in the cells is gassing (bubbling) freely. The specific gravity reading from each cell should be very close to the others. If not, the battery probably has a bad cell(s), and a new one should be fitted. 16 Some maintenance-free (sealed) batteries have built-in hydrometers on the top, indicating the state of charge by the colour displayed in the hydrometer window. Normally, a bright-coloured hydrometer indicates a full charge, and a dark hydrometer indicates the battery still needs charging. Check the battery manufacturer’s instructions to be sure you know what the colours mean.

17 If the battery is sealed and has no built-in hydrometer, you can connect a digital voltmeter across the battery terminals to check the charge. A fully-charged battery should read 12.6 volts or higher. 18 Further information on the battery and jump starting can be found in Chapter 5 and at the front of this manual.

14 Spark plug check and

renewal

1 Before beginning, obtain the necessary tools, which will include a spark plug socket and a set of feeler blades. Special spark plug gap gauges can be obtained from certain spark plug manufacturers (see illustration). 2 The best procedure to follow when renewing the spark plugs is to purchase the new spark plugs beforehand, adjust them to the proper gap, and then renew each plug one at a time. When buying the new spark plugs, it is important to obtain the correct plugs for your specific engine. This information can be found in the Specifications section in the front of this Chapter. 3 With the new spark plugs at hand, allow the engine to cool completely before attempting plug removal. During this time, each of the new spark plugs can be inspected for defects and the gaps can be checked. 4 The gap is checked by inserting the proper thickness gauge between the electrodes at the tip of the plug (see illustration). The gap between the electrodes should be the same as that given in the Specifications. The wire should just touch each of the electrodes. If the gap is incorrect, use the notched adjuster to bend the curved side of the electrode slightly until the proper gap is achieved (see

illustration). Note: When adjusting the gap of a new plug, bend only the base of the earth electrode, do not touch the tip. If the earth electrode is not exactly over the centre electrode, use the notched adjuster to align the two. Check for cracks in the porcelain insulator, indicating the spark plug should not be used.

1•17

14.4b To change the gap, bend the earth

electrode only, as indicated by the arrows,

and be very careful not to crack or chip the

porcelain insulator surrounding the centre

electrode

14.4a Spark plug manufacturers

recommend using a wire-type gauge when

checking the gap - if the wire does not

slide between the electrodes with a slight

drag, adjustment is required

14.1 Tools required for changing spark plugs

1 Spark plug socket - This will have special

padding inside to protect the spark plug’s porcelain insulator

2 Torque wrench - Although not mandatory,

using this tool is the best way to ensure the plugs are tightened properly

3 Ratchet - Standard hand tool to fit the

spark plug socket

4 Extension - Depending on model and

accessories, you may need special extensions and universal joints to reach one or more of the plugs

5 Spark plug gap gauge - This gauge for

checking the gap comes in a variety of styles. Make sure the gap for your engine is included. Feeler blades may be used instead

Every 12 000 miles

5 With the engine cool, remove the HT lead from one spark plug. Do this by grabbing the connector at the end of the wire, not the lead itself (see illustration). Sometimes it is necessary to use a twisting motion while the connector and HT lead are pulled free. 6 If compressed air is available, use it to blow any dirt or foreign material away from the spark plug area. A common bicycle pump will also work. The idea here is to eliminate the possibility of debris falling into the cylinder as the spark plug is removed. 7 Place the spark plug socket over the plug, and remove it from the engine by turning it anti-clockwise (see illustration). 8 Compare the spark plug with those shown in the accompanying photos to get an indication of the overall running condition of the engine. 9 Apply a little copper-based anti-seize compound to the threads of the new spark plug. Locate the plug into the head, screwing it in with your fingers until it no longer turns, then tighten it with the socket. If available, use a torque wrench to tighten the plug to ensure that it is seated correctly. The correct torque figure is included in this Chapter’s Specifications.

10 Before pushing the HT lead onto the end of the plug, inspect it as outlined in Section 15. 11 Attach the HT lead to the new spark plug, again using a twisting motion on the connector until it is firmly seated on the spark plug. 12 Follow the above procedure for the remaining spark plugs, renewing them one at a time to prevent mixing up the spark plug HT leads.

15 Spark plug HT leads,

distributor cap and rotor -

check and renewal

1 The spark plug HT leads should be checked at the recommended intervals, and whenever new spark plugs are fitted in the engine. 2 Begin this procedure by making a visual check of the spark plug HT leads while the engine is running. In a darkened garage (make sure there is ventilation) start the engine and observe each HT lead. Be careful not to come into contact with any moving engine parts. If there is a break in the wire, you will see arcing or a small spark at the damaged area. If arcing is noticed, make a note to obtain new HT leads, then allow the engine to cool. 3 Disconnect the battery negative cable.

Caution: If the radio in your vehicle is equipped with an antitheft system, make sure you have the correct activation code before disconnecting the battery.

Note: If, after connecting the battery, the wrong language appears on the instrument panel display, refer to page 0-7 for the language resetting procedure.

4 The HT leads should be inspected one at a time to prevent mixing up the firing order, which is essential for proper engine operation. 5 Disconnect the HT lead from the spark plug. Do not pull on the lead itself, only on the connector. 6 Inspect inside the connector for corrosion, which will look like a white crusty powder. Push the HT lead and connector back onto the end of the spark plug. It should be a tight fit on the plug end. If it is not, remove the lead and use pliers to carefully crimp the metal terminal inside the connector until it fits securely on the end of the spark plug. 7 Using a clean rag, wipe the entire length of the HT 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, since the conductor might break. 8 Disconnect the HT lead from the distributor. Again, pull only on the connector. Check for corrosion and a tight fit in the same manner as the spark plug end. Renew the HT lead in the distributor if necessary. 9 Check the remaining spark plug HT leads, making sure they are securely fastened at the distributor and spark plug when the check is complete. 10 If new spark plug HT leads are required, purchase a set for your specific engine model. Lead sets are available pre-cut, with the connectors already fitted. Remove and renew the HT leads one at a time, to avoid mix-ups in the firing order. 11 Loosen the screws or detach the clips and remove the distributor cap (see illustration). Remove the screws (if applicable) and pull the rotor off the shaft (see illustration). Check the distributor cap and rotor for wear. Look for cracks, carbon tracks and worn, burned or loose contacts (see illustrations). Renew the cap and rotor if defects are found. It is common practice to fit a new cap and rotor whenever new spark plug HT leads are fitted. When fitting a new cap, remove the HT leads from the old cap one at a time, and attach

1•18

15.11b Use an Allen key to remove the screws, then lift the rotor off the shaft

(later models)

15.11a On later models, loosen the screws and detach the distributor cap up so you

can inspect the inside

14.7 Use a socket spanner with an

extension to unscrew the spark plugs

14.5 When removing the spark plug HT leads, pull only on the connector

Every 12 000 miles

Where there might be difficulty in inserting the spark plugs into the spark plug holes, or the possibility of crossthreading them into the head, a short piece of rubber or plastic tubing can be fitted over the end of the spark plug. The flexible tubing will act as a universal joint to help align the plug with the plug hole, and should the plug begin to cross-thread, the hose will slip on the spark plug, preventing thread damage.

them to the new cap in the exact same location - do not simultaneously remove all the HT leads, or firing order mix-ups may occur.

16 Manual transmission

lubricant level check

1 The transmission has a filler/level plug which must be removed to check the lubricant level. If the vehicle is raised to gain access to the plug, be sure to support it safely - do not crawl under a vehicle which is supported only by a jack! Note: The vehicle should be level to

give an accurate lubricant check.

2 Remove the plug from the side of the

transmission (see illustration) and use your little finger to reach inside the plug from the housing and feel the lubricant level. It should be at or very near the bottom of the plug hole. 3 If it isn’t, add the recommended lubricant through the plug hole with a syringe or squeeze-bottle, until it just starts to run out of the hole. Refer to “Lubricants and fluids” at the beginning of this Chapter for the correct lubricant type. The manual transmissions on some later or high-performance models are filled with automatic transmission fluid (ATF). Such transmissions normally carry a sticker to this effect near the filler/level plug. Refer to a BMW dealer if still in doubt. 4 Refit the plug and tighten securely. Check for leaks after the first few miles of driving. 5 If regular topping-up is required, this can only be due to a leak which should be found and repaired before it becomes serious.

17 Differential lubricant level

check

1 The differential has a filler/level plug which must be removed to check the lubricant level. If the vehicle is raised to gain access to the plug, be sure to support it safely - do not

crawl under the vehicle when it’s supported only by the jack! Note: The vehicle should be

level to give an accurate lubricant check.

2 Remove the filler/level plug from the differential (see illustration). Use an Allen key to unscrew the plug. 3 Use your little finger as a dipstick to make sure the lubricant level is up to the bottom of the plug hole. If not, use a syringe or squeezebottle to add the recommended lubricant until it just starts to run out of the hole.

4 Refit the plug and tighten it securely. 5 If regular topping-up is required, this can

only be due to a leak which should be found and repaired before it becomes serious.

18 Valve clearances -

check and adjustment

Note: This procedure does not apply to the M40 engine, which has automatic adjusters.

1 The valve clearances can be checked with the engine hot or cold, but note that different values are specified, depending on engine temperature. If it is wished to check/adjust the valve clearances with the engine hot, if necessary start and run the engine until it reaches normal operating temperature, then shut it off.

Caution: If the clearances are checked

with the engine hot, extra care must be taken to avoid burns.

2 Remove the valve cover from the engine (see Chapter 2A). 3 Turn the engine as necessary until No 1 piston (front) is at Top Dead Centre (TDC) on the compression stroke (see Chapter 2A). 4 Check the valve clearances for No 1 cylinder. The valve clearances can be found in the Specifications Section at the beginning of this Chapter. 5 The clearance is measured by inserting the specified size feeler gauge between the end of the valve stem and the rocker arm adjusting eccentric. You should feel a slight amount of

1•19

15.11d The rotor arm should be checked for wear and corrosion as indicated here

(if in doubt about its condition, buy a new

one)

15.11c Shown here are some of the common defects to look for when

inspecting the distributor cap (if in doubt

about its condition, fit a new one)

18.6 The valve clearance is adjusted by turning the eccentric with a wire hook -

once the specified clearance is obtained,

tighten the locknut with a spanner, then

remove the feeler gauge

17.2 Remove the differential filler/level

plug with an Allen key, and make sure the

lubricant is level with the bottom of the

hole

16.2 Use a large Allen key to remove the filler/level plug (arrowed) and check the

lubricant level with your little finger. It

should be level with the bottom of the hole

- if it’s low, add lubricant

Every 12 000 miles

drag when the feeler gauge is moved back and forth.

6 If the gap is too large or too small, loosen the locknut, insert a hook made from largediameter metal wire, and rotate the eccentric to obtain the correct gap (see illustration).

7 Once the gap has been set, hold the eccentric in position with the hook, and retighten the locknut securely. Recheck the clearance - sometimes it’ll change slightly when the locknut is tightened. If so, re-adjust until it’s correct.

8 On the M10 engine, the valves are adjusted in the firing order, which is 1-3-4-2. After adjusting No 1 cylinder valves, rotate the crankshaft half a turn (180º), then check and adjust the valves on No 3 cylinder. Repeat the procedure on the remaining cylinders.

9 On M20 and M30 engines, the valves are adjusted following the firing order, which is 1-5-3-6-2-4. After adjusting No 1 cylinder valves, rotate the crankshaft a third of a turn (120º), then check and adjust the valves on No 5 cylinder. Repeat the procedure for the remaining cylinders.

10 Refit the valve cover (use a new gasket) and tighten the mounting nuts evenly and securely.

11 Start the engine and check for oil leakage between the valve cover and the cylinder head.

19 Throttle linkage -

check and lubrication

1 The throttle linkage should be checked and lubricated periodically to ensure its proper operation. 2 Check the linkage to make sure it isn’t binding. 3 Inspect the linkage joints for looseness, and the connections for corrosion and damage, renewing parts as necessary (see

illustration). 4 Lubricate the connections with spray

lubricant or lithium-based grease.

20 Air filter renewal

Carburettor engines

1 Release the spring clips, then unscrew the centre nut and lift off the cover. 2 Remove the air filter element, and wipe clean the air cleaner body and cover 3 Fit the new air filter element, then refit the cover using a reversal of the removal procedure.

Fuel injection engines

4 Loosen the clamp on the air intake duct, and detach the duct (see illustration).

5 Release the air cleaner cover retaining clips (see illustration). 6 Rotate the cover up, lift it off and lift the

element out, noting which way round it is fitted (see illustrations). 7 Wipe the inside of the air cleaner housing with a clean cloth, then fit the new element. If the element is marked TOP, be sure the marked side faces up.

8 Refit the cover and secure the clips. 9 Connect the air duct and tighten the clamp

screw.

21 Fuel system check

Warning: Fuel is extremely flammable, so take extra precautions when you work on

any part of the fuel system. Don’t smoke, or allow open flames or bare light bulbs, near the work area. Don’t work in a garage where a natural gas-type appliance (such as a water heater or clothes dryer) with a pilot light is present. Work in a wellventilated area. If you spill any fuel on your skin, rinse it off immediately with soap and water. When you perform any kind of work on the fuel system, wear safety glasses, and have a fire extinguisher on hand. Mop up spills immediately, but do not store fuel-soaked rags where they could ignite.

1 If you smell fuel while driving or after the vehicle has been sitting in the sun, inspect the fuel system immediately. 2 Remove the fuel filler cap and inspect it for damage and corrosion. The gasket should have an unbroken sealing imprint. If the gasket is damaged or corroded, fit a new cap. 3 Inspect the fuel feed and return lines for cracks. Make sure that the connections between the fuel lines and the carburettor or fuel injection system, and between the fuel lines and the in-line fuel filter, are tight.

Warning: On fuel injection

models, the fuel system must be

depressurised before servicing

fuel system components, as

outlined in Chapter 4.

1•20

20.6b . . . and lift the air filter element out

20.6a Rotate the cover upwards . . .

20.5 Use a screwdriver to detach the air cleaner cover clips

20.4 Detach the duct from the air cleaner housing

19.3 Check and lubricate the throttle

linkage at the points shown (arrowed) -

fuel injection engine shown

Every 12 000 miles

+ 198 hidden pages