book1 sample chapter=mach-comp'nt

8/4/2019 Book1 Sample Chapter=Mach-comp'Nt

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CHAPTER 8 ENGINE FUNDAMENTALS V

Part 1 Introduction to motor vehicles 11 Motor vehicle components 3

2 Workshop safety 17

3 Workshop practices 29

4 Tools and their use 45

5 Measuring and checking 69

6 Friction and bearings 87

7 Seals, gaskets and sealants 103

8 The environment and the automotive service

industry 117

Part 2 Engines and engine systems 1319 Engine fundamentals 133

10 Engine construction and components 149

11 Cooling system and service 169

12 Engine-lubricating systems 191

13 EFI fuel systems 207

14 Carburettor fuel systems 223

15 Gas fuel systems 257

16 Intake and exhaust systems 279

Part 3 Manual transmissions and drives 29517 Clutches 297

18 Clutch service 311

19 Manual transmission and transaxles 325

20 Manual transmission and transaxle

service 351

21 Drive lines and shafts 375

22 Rear axles and final drives 393

23 Rear-axles and final-drive service 411

Part 4 Running gear 43324 Tyres, wheels and balance 435

25 Brakes 455

26 Brake service 485

27 Suspension systems 507

28 Suspension service 527

29 Steering systems 549

30 Steering-system service 573

31 Wheel alignment 593

Part 5 Maintenance 61532 Fuels, fluids and lubricants 617

33 Service and maintenance 631

34 Basic mechanics and diagnosis 645

Part 6 Basics of the electrical system 65935 Basic electrics 661

36 Effects and applications of electric

currents 677

37 Basic electronics 695

38 The battery 711

Appendix: The SI system of measurement 727

Common abbreviations 734

Glossary 735

Index 751

About the authors xiii

Competency grid xiv

Preface xvi

Acknowledgments xvi

Supplemements for Instructors


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About the authors xiii

Competency grid xiv

Preface and Acknowledgments xvi

Supplements for instructors xviii

Motor vehicle components 3Mechanical arrangements 4

Sections of a motor vehicle 4

Hybrid-drive vehicles 5

The engine assembly 5

Vehicle construction 5

The drive train 6

Transmissions 9

Running gear 10

Electrical system 13

Body and associated parts 13Names of components and parts 15

Technical terms 15

Review questions 15

Workshop safety 97Personal safety 98

Other personal safety issues 99

Machine and equipment safety

Motor vehicle safety 99

Safety with vehicle components 101

Engine safety 101

Battery safety 102Hazardous materials

Emergency procedures

Fire safety 103

Fires 103

Fire extinguishers 104

First aid 105

Technical terms 105

Review questions 105

Workshop practices 17 Automotive service procedures 18

Workshop operations 20

Production processes 21

Fasteners 23

Locking devices 25

Screw threads 26

V-threads

Sources of information 28

Vehicle identification 30

Technical terms 30Review questions 30

Tools and their use 33Tools for turning 34

Tools for holding and gripping 38

Tools for hammering and driving 39

Tools for cutting and forming 41

Tools for drilling and reaming 44

Tools for threading 46

Tools and materials for grinding and abrading 48

Tools for pulling and pushing 51

Portable power tools

Special service tools 52Technical terms 52

Review questions 52

Measuring and checking 53Measuring instruments 54

Micrometers 55

Reading micrometers 57

Accuracy and care of micrometers 59

PART 1 INTRODUCTION TO MOTOR VEHICLES


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Vernier calipers 59

Dial gauge and its use 60

Hole gauges

Depth gauges 61

Marking and checking 61

Tools for marking and checking 62

Other gauges and instruments 65

Electrical test instruments 66

Technical terms 67

Review questions 67

Friction and bearings 69Friction 70

Types of friction 70

Making use of friction 71

Bearings 71

Plain bearings 73

Antifriction bearings 74

Special types of bearings 76

Removing and installing bearings 77

Cleaning and checking bearings 78

Bearing adjustments 79Bearing failures 80

Antifriction bearing defects 81

Technical terms 83

Review questions 83

Seals, gaskets and sealants 85Purpose of oil seals 86

Types of oil seals 86

Servicing oil seals 88

Gaskets 91

Gasket materials 92

Handling and storing gaskets 93

Sealants and sealing compounds 93

Installing gaskets 93How to make a gasket 95

Pipes, hoses and connections 95

Technical terms 96

Review questions 96

The environment and the automotive

industry 00Introduction 00

Legal responsibilities

Water quality

Liquid waste and chemical storage

Solid waste Air quality

Noise

An environmental checklist

Technical terms 96

Review questions 96

Engine fundamentals 109

Actions within a cylinder 110Reciprocating to rotary motion 110

Cycles of engine operation 112

Four-stroke cycle (petrol engine) 112

Two-stroke cycle (petrol engine) 116

Diesel engine operation 118

Rotary engine 119

Multicylinder engines 119

Engine terms and definitions 121

Engine systems 122

Engine classifications 121

Technical terms 122


Engine construction and components 125

Engine construction 126Components of an engine assembly 129

Engine features 130

Working on engines general 132

Working on the underside of the engine 135

Working on the front of the engine 136

Working on the top of the engine 136

Working on engine ancillaries 138

Working on engine electrical systems 139

Technical terms 141


VII

PART 2 ENGINES AND ENGINE SYSTEMS


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Cooling system and service 143Basic cooling system 144

Heat and temperature 145

Heat transfer 146

Liquid-cooling systems 146

Cooling-system components 148

Radiator assembly 152

Radiator pressure cap and reservoir 153

Coolant 154

Cooling-system service 155

Cooling-system repairs 158

Water pump overhaul 160Cooling-system problems 161

Trouble diagnosis guide 162

Technical terms 162


Engine-lubricating systems 163Engine lubrication 164

Oil circulation 165

Oil pumps 167

Oil pump service 169

Oil filters 170

Oil coolers 171

Lubrication of engine bearings 173

Crankcase ventilation 174

Lubricating-system maintenance 175

Lubricating-system problems 177

Technical terms 178


EFI fuel systems 179Petrol as a fuel 180

Airfuel ratio 180

Types of EFI systems 181

Basic multipoint EFI system 181

Multipoint fuel systems 181Fuel-supply system components 184

Air intake system components 189

Electronic control components 190

Checks and precautions 191

Service requirements 193

Technical terms 193


Carburettor fuel systems 195Carburettor fuel system 196

Carburettors 198

Air and fuel flow in a carburettor 199

Carburettor operation 199

Carburettor systems 201

Carburettor construction 201

General carburettor design 203

Carburettor external construction 204

Single-barrel and multibarrel carburettors

Throttle-valve operation

Mixture correctionAutomatic chokes

Manual chokes

Other carburettor components

Carburettor service and checks 205

Basic carburettor problems 207

Servicing fuel pumps 207

Testing mechanical fuel pumps 208

Checking electric pumps 210

Fuel system problems 210

Technical terms 211


Gas fuel systems 213Gas-fuelled vehicles 214

LPG and NGV 214

Location of LPG components 215

LPG fuel container assembly 216

Fuel container sub-compartment 217

Fuel filler assembly 219

Components of the supply subsystem 220

Converter assembly 220

Airgas mixer 223

LPG fuel system controls 224

LPG fuel system components 224Converter with stepper motor 225

LPG liquid and vapour injection

NGV fuel systems 227

Servicing LPG fuel systems 228

Safety precautions with gas 229

Technical terms 230


VIII


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Clutches 249Purpose of the clutch 250

Types of clutches 250

The clutch assembly 250

Diaphragm clutch operation 251

Diaphragm clutch components 252

Clutch controls 255

Other clutch features 258

Pull-type clutches 259

Clutch with central release 260

Dual-mass flywheel 260Technical terms 261


Clutch service 263General checks and adjustments 264

Adjusting mechanical controls 264

Servicing mechanical controls 265

Adjusting hydraulic controls 265

Servicing hydraulic controls 266

Bleeding the clutch system 269

Major clutch service 269

Repairs to pressure-plate assemblies 273

Clutch housing alignment 273 Analysing clutch problems 273

Diagnosing clutch noise 274

General clutch problems 275

Technical terms 276


Manual transmissions andtransaxles 277Purpose of a transmission 278

Types of gears 278

Gear ratio 279

Basic transmission 280

Basic transmission power flow 281

Sliding and synchromesh gears 281

Basic synchromesh transmission 283

Five-speed synchromesh transmission 285

Power flow through a five-speed

transmission 286

Six-speed transmission

Transaxles 286

Transaxle construction 286

Transaxle operation 290

Synchromesh operation 293

Types of synchromesh 295

Gearshift mechanisms 295Technical terms 300


Manual transmission andtransaxle service 301Service operations 302

Rear-wheel-drive transmissions 303

Dismantling transmissions 307

Dismantling and checking components 307

Identifying internal components of a

transmission 311

Transaxles 312Identifying internal components of a

transaxle 313

Dismantling transaxles 316

Reassembling transaxles 317

Inspection of parts (all transmissions) 317

Points relating to reassembly 319

Removing transmissions and transaxles 321

Transmission and transaxle fault diagnosis 321

Road testing and diagnosis 321

Transmission service summary 322

Technical terms 324


IX

PART 3 MANUAL TRANSMISSIONS AND DRIVES

Intake and exhaust systems 231 Air cleaners 232

Carburettor air cleaners 232

EFI air cleaners 234

Diesel air cleaners 236

Air-cleaner service 236

Engine manifolds 238

Intake-system problems 240

Exhaust systems 240

Exhaust-system service 243

Exhaust-system problems 244

Technical terms 246



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Drive lines and shafts 325Rear-wheel drive 326

Universal joints 326

Constant-velocity joints 328

Alignment of universal joints (RWD) 329

Removing and replacing propeller shafts 331

Servicing cross-and-yoke joints 331

Servicing a Lbro joint 334

Front-wheel drive 335

Constant-velocity joints (FWD) 337

Servicing constant-velocity joints (FWD) 338

Technical terms 340


Rear axles and final drives 343Basic rear-axle assembly (RWD) 344

Rigid rear axles 344

Final drive and differential 346

Axle shafts for rigid rear axles 349

Rear-axle bearings 349

Differential 350

Limited-slip differentials 352

Dynamic performance control

Rear axles for independent rear suspension 355

Transaxle final drive 357

Four-wheel drive 359

Technical terms 359


Rear-axle and final-drive service 361General rear-axle service points 362

Removing axle shafts and bearings 362

Servicing differential assemblies 367

Servicing a banjo-axle differential 367

Servicing unitised rear-axle differentials 371

Servicing IRS final drives 372Crown wheel and pinion adjustments 374

Checking gear tooth contact 376

Bearing preload pinion and side

bearings 377

Limited-slip differential service 379

Transaxle final-drive service 380

Transaxle with crown wheel and pinion 380

Summary of differential adjustments 381

Diagnosis of rear-axle noises 381

Technical terms 382


Tyres, wheels and balance 387Tyre construction 388

Types of tyre construction 389

Characteristics of tyres 390

Tyre profiles 390

Tyre sizes and identification 391

Tyre tread patterns 392

Australian Design Rules 393

Tyre wear 394Tyre rotation 396

Wheels 397

Removing and fitting tyres 398

Light-truck wheels and tyres 399

Wheel balance 400

Balancing wheels 402

Technical terms 404


Brakes 407Basic brake system 408

Hydraulic principles 408

Brake hydraulic systems 410

Master cylinders 410

Compensating-type master cylinder 413

Centre-valve master cylinder 414

Valves in the hydraulic system 416

Wheel cylinders 418

Hydraulic brake fluid 420

Brake booster 420

Drum-brake assemblies 423

Brake-shoe assemblies 424

Disc-brake assemblies 426

Parking brakes 430

Technical terms 432


Brake service 435Maintenance and inspection 436

Brake booster 438

Hydraulic system service points 439

Bleeding brakes 441

Master-cylinder service 442

Drum-brake service 443

Drum-brake adjustments 446Self-adjusting drum brakes 447

X

PART 4 RUNNING GEAR


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Disc-brake service 448

Parking brakes 451

Brake tools 453

Fault diagnosis 454Technical terms 455


Suspension systems 469General suspension designs 470

Leaf springs 471

Rear suspension with leaf springs 471

Front suspension with leaf springs 473

Types of coil springs 474

Front suspension with coil springs 474

Strut or McPherson suspension 476

Rear suspension with coil springs 477

Independent rear suspensions with

struts 479

Rear suspension with swing axles 480

Torsion rear axle 480

Torsion bar suspension 483

Shock absorbers 483

Height-control suspension 486

Technical terms 486


Suspension service 489Maintenance 490

Dismantling and reassembling procedures 490Ball joint front suspension 491

Strut (McPherson) suspensions 492

Rigid rear axle with coil springs 494

Independent rear suspension (RWD vehicles) 495

Rigid rear axle with leaf springs 496

Dismantling and reassembling struts 498

Servicing components 499

Servicing hubs and bearings 502

Hubs with tapered roller bearings 502

Hubs with unitised bearings 504

Other bearing arrangements 506

Checking suspension parts 507

Servicing shock absorbers 509Technical terms 510


Steering systems 511Steering systems 512

Rack-and-pinion steering systems 512

Steering systems with worm gearing 513

Steering and suspension angles 514

Steering boxes 516

Rack-and-pinion steering boxes 517

Rack-and-pinion power steering 518

Rack-and-pinion power steeringcomponents 519

Speed-sensitive rack-and-pinion power

steering 521

Electro-hydraulic power steering 522

Electric power steering 523

Steering boxes with worm gearing 524

Power steering for worm-type boxes 525

Four-wheel steering 528

Four-wheel-steering systems 529

Four-wheel steering with rear power

cylinder 530

Other steering features 533

Technical terms 534


Steering-system service 535Servicing steering linkage 536

Steering-column service 538

Power-steering maintenance 540

Rack-and-pinion steering service 542

Rack-and-pinion power-steering service 545

Analysing power-steering problems 547

Servicing a recirculating-ball steering box 547

Worm-type steering box adjustments 550

Recirculating-ball box with powersteering 551

Steering faults 551

Technical terms 552


Wheel alignment 553Steering and suspension angles 554

Front-suspension and steering adjustments 556

Caster and camber adjustments 556

Toe adjustments 558

Adjustments for toe-out-on-turns 560

Rear-suspension adjustments 560

Wheel-alignment equipment 561

Types of wheel aligners 562

Using wheel aligners 565

Front-wheel alignment 568

Rear-wheel alignment 569

Function and effects of the various angles 569

More about suspension angles 571

Technical terms 573


XI


8/18

XII

Fuels, fluids and lubricants 577Crude oil and its products 578

Petrol 578

Ethanol

Gas fuels 580

Automotive diesel fuels 581

Alternative fuels

Lubricating oil 582

Grease 585

Transmission oils 586

Hydraulic brake fluids 587

Technical terms 588


Service and maintenance 589Servicing new vehicles 590

New vehicle services 590

Scheduled maintenance services 590

Maintenance items 592

Service intervals 597

Special services 598

General service and repairs 598

Lifting and jacking 598

Towing and recovering 600

Technical terms 601


Basic mechanics and diagnosis 603Diagnosis 604

Forces that produce stress 604Failure analysis 607

Analysing shaft failures 607

Analysing fastener failures 608

Analysing excessive wear 609

Noise vibration and harshness (NVH) 610

Analysing gear problems 611

Bearing problems 613

Materials and their use 613

Other means of diagnosis 614

Technical terms 614


PART 6 BASICS OF THE ELECTRICAL SYSTEM

Basic electrics 619 Automotive electrical components 620

Nature of electricity 621

Electron flow 622

Current flow 623

Types of electrical materials 623

Summary of basic electrics 624

Practical conductors, resistors and

insulators 625

Factors affecting current flow 627The language of electricity 627

Electrical circuits 630

Parallel and series connections 630

Voltage drop in a circuit 632

Technical terms 633


Effects and applications of electric

currents 000Effects of an electric current 636

Heating effect of a current 636

Chemical effect of a current 637Magnetic effect of a current 638

Theory of magnetism 638

Electromagnetism 640

Solenoids and electromagnets 641

Electromagnetic switches (relays) 643

Electrical measuring instruments 644

Electromagnetic induction 645

Electric motors 648

Direct and alternating current 649

Technical terms 649


Basic electronics 651Electronics 652

Electronic semiconductors 653

Electronic components diodes and

transistors 654

Other electronic components 656

Use of electronic components 658

Electronic systems 660

Micro-computer 662

Body electronic module 663

Technical terms 665


PART 5 MAINTENANCE


9/18

Aur Description Volume Chapter

AURC270103A Apply safe working practice 1 2

AURC270789A Communicate effectively in the workplace 1 2,3

AURE218664A Remove and replace electrical/electronic units/assemblies 2 24, 25, 26, 27

AURE218676A Test, service and repair batteries 1 38

AURE219331A Install, test and repair low-voltage wiring/lighting systems 1 3538

2 2627

AURE219531A Install ancillary electrical components 2 2636

AURE224008A Carry out soldering of electrical wiring/circuits 2 27

AURE318966A Repair instruments and warning systems 2 28

AURE320871A Service and repair electronically controlled steering systems 1 29, 30

AURE320971A Service and repair electronically controlled suspension systems 1 27, 28

AURE321066A Repair electronic systems 1 37

AURE321271A Service and repair electronic drive management systems 2 27

AURE321371A Service and repair electronic body management systems 2 26, 27, 29

AURE321471A Service and repair electronically controlled antilock braking systems 1 26

2 30

AURE321571A Service and repair electronically operated traction control system 2 30

AURE321671A Service and repair electronically operated stability control 2 30

AURE321171A Service and repair electronic spare ignition engine management systems. 2 11

AURE218676A Test, service and charge batteries 1 38

AURE218708A Carry out repairs to single electrical circuits 1 35

2 26, 27

AURE320666A Repair ignition systems 2 11

AURE319266A Repair starting systems 2 24

AURE319166A Repair charging systems 2 25

AURE318866A Repair electrical systems 2 27

AURT200108A Carry out servicing operations 1 33

AURT205166A Repair exhaust system components 1 15

AURT201170A Inspect and service engines 1 9, 10

AURT202170A Inspect and service cooling systems 1 11

AURT203170A Service petrol fuel systems 2 14

AURT206670A Inspect and service transmissions (manual) 1 19, 20

AURT207170A Inspect and service transmissions (automatic) 2 1922

AURT210170A Inspect and service braking systems 1 2526


10/18

XV


AURT212670A Service final drive assemblies 1 22, 23

AURT213170A Service final drive (drive line) 1 21

AURT215170A Inspect and service steering systems 1 29, 30

AURT216170A Inspect an service suspension systems 1 27, 28

AURT217606A Balance wheels and tyres 1 24

AURT270278A Use and maintain workplace tools and equipment 1 25

AURT200368A Select and use bearings, seals, gaskets, sealants and adhesives 1 6, 7

AURT201164A Remove and install engine assemblies 2 1

AURT202166A Repair cooling systems 1

AURT203670A Service diesel fuel injection systems 2 15, 16, 17

AURT204670A Inspect and service emission control systems 2 12

AURT205166A Repair exhaust system components 1 16

AURT213165A Remove and refit drive-line components 1 21, 22, 23

AURT217108A Carry out wheel alignment operations 1 31

AURT217665A Remove, fit and inspect wheel assemblies 1 24

AURT217668A Select tyres and rims for specific applications (light) 1 24

AURT217766A Remove, inspect, repair and fit tyres and tubes (light) 1 24

AURT217865A Remove and refit wheel hubs and associated brake components 1 25

AURT225667A Use and maintain measuring equipment 1 5, 8

AURT216170A Inspect and service suspension systems 1 27, 28

AURT209170A Service hydraulic systems 2

AURT301383A Dismantle, assemble and repair engine block and sub-assemblies 2 4, 5, 6, 7

AURT301483A Recondition cylinder heads 2 2, 3

AURT303666A Repair diesel fuel systems 2 15, 16, 17

AURT304270A Service LPG Fuel systems 1 15, 32

AURT305671A Inspect and repair engine forced induction systems 2 13

AURT307166A Repair transmissions (automatic) 2 1922

AURT318054A Provide advice on the effects of wheel and tyre combinations 1 24

AURT401145A Overhaul engines and associated engine components 2 18

AURT403145A Overhaul petrol fuel system components 1 10, 14

AURT406145A Overhaul clutch assemblies 1 171

AURT406645A Overhaul transmissions (manual) 1 1920

AURT407145A Overhaul transmissions (automatic) 2 1922

AURT410145A Overhaul braking system components (light) 1 2526


11/18

XVI PART 3 INTRODUCTION TO THE ENGINE


AURT412645A Overhaul final-drive assemblies 1 21, 22, 23

AURT415145A Overhaul steering system components 1 2930

AURT466208A Carry out diagnosis of complex system faults 1 34

AURT202166A Repair cooling systems 1 11

AURT271781A Implement and monitor environmental regulations in the automotive 1 8mechanical industry

AURT301166A Repair engines and associated engine components 2 18

AURT303166A Repair petrol fuel systems 1 10, 14

AURT304666A Repair and replace emission control systems 2 12

AURT306170A Inspect, service and/or repair clutch assemblies and associated

operating system components 1 1718

AURT306666A Repair transmissions (manual) 1 1920

AURT310166A Repair hydraulic braking systems 1 25, 26

AURT312666A Repair final-drive assemblies 1 22, 23

AURT313166A Repair final drive (drive line) 1 21

AURT315166A Repair steering systems 1 2930

AURT316166A Repair suspension systems 1 2728

AURT366108A Carry out diagnostic procedures 1 34

AURV327164A Remove and replace supplementary restraint systems (SRS) 2 33

XVI


12/18

CHAPTER 1 MOTOR VEHICLE COMPONENTS 3

Mechanicalarrangements

Sectionsofamotorvehicle

Hybrid-drivevehicles

Theengineassembly

Vehicleconstruction

Thedrivetrain

Transmissions

Runninggear

Electricalsystem

Bodyandassociatedparts

Namesofcomponentsandparts

Technicalterms

Reviewquestions


13/18

4 PART 1 INTRODUCTION TO MOTOR VEHICLES

A motor vehicle is made up of a large number of parts

which are assembled together during manufacture.

Some parts are large and others are quite small.

Many parts are fitted together to form larger com-

ponents. Some parts are bolted together while

others, such as the body panels and subframes, arewelded together.

Motor vehicles vary greatly in design and body

style, and the term motor vehicle can be used to

include passenger cars, station wagons, vans, utilities,

trucks, buses and coaches. In fact, any wheeled

vehicle that operates on roads can be included.

In this book, most of the information will relate

to passenger vehicles and light commercial vehicles.

However, the basic principles involved apply to all

motor vehicles and, in many instances, to vehicles that

do not usually operate on roads, such as agricultural

tractors and industrial and construction equipment.

Mechanical arrangementsThere are two basic arrangements of the major

mechanical components of passenger and light

commercial vehicles: front-wheel drive and rear-

wheel drive. These are shown in simplified form in

Figures 1.1 and 1.2 with their parts identified. While

the main difference is whether the front wheels or

the rear wheels drive the vehicle, this can affect a

number of other components, such as the mounting

of the engine, the transmission, the drive line and the

suspension.

In addition to these two basic arrangements,

there are also four-wheel-drive vehicles. These have

additional transmission and drive-line componentsthat carry the drive to all four wheels of the vehicle.

In many four-wheel-drive vehicles, front-wheel

drive is selected by the driver only when it is needed,

but other vehicles, referred to as all-wheel drives,

operate in four-wheel drive at all times.

Sections of a motorvehicle

A motor vehicle consists of a number of sections which,for convenience, can be considered as follows:1 The engine assembly, which is the source of

power.2 The frame or chassis, which forms the basic

structure to support the engine and the various

mechanical components.3 The drive train, which has gears and shafts to

connect the engine to the driving wheels.4 The running gear, consisting of the wheels,

tyres, suspension, steering and brakes, which

enables the vehicle to operate on the road.

2 3 4 5 6 7 8 9 10 11 12 13

14

15

16171819201

Figure 1.1 Skeletal arrangement of a rear-wheel-drive vehicle

1 engine assembly, 2radiator, 3alternator, 4front suspension, 5front disc brake, 6steering assembly, 7torque converter, 8automatic

transmission,9

handbrake,10

propeller shaft,11

rear suspension,12

rear brake,13

shock absorber,14

rear-axle assembly,15

fuel tank,16final drive, 17exhaust system, 18catalytic converter, 19wheel hub, 20battery


14/18


5 The electrical system, which includes the

battery, wiring, lights, starter, alternator and

other electrical components.6 The body of the vehicle, which provides seating

for the driver and passengers and, in commercial

vehicles, carries loads.

To service these various parts of a motor vehicle,

it is necessary to know the names of the various

components, their location on the vehicle, and their

purpose or function.

It is also necessary to understand how components

operate and to be familiar with their construction

and design. A knowledge of adjustments and servic-

ing requirements is also important, together with

accepted methods of carrying out repairs.

Hybrid-drive vehiclesHybrid vehicles have an internal combustion engine

combined with an electric motor to provide the power

to drive the vehicle. The reason for this is to improve

fuel economy and to reduce exhaust emissions. The

engine can be designed so that it is smaller than

normal and as a result is more fuel efficient. Theelectric motor produces no emissions.

The basic hybrid arrangement is shown in

Figure 1.3 on the following page with its main parts

identified. Depending on driving conditions, powerto drive the vehicle is delivered by the engine, by the

electric motor, or by a combination of the engine and

the electric motor.

It has a fuel tank to supply petrol to the engine and

high-voltage batteries to provide power to the electric

motor. The battery is recharged by a generator when

the electric motor is not in use. More information on

hybrid vehicles can be found in Volume 2.

The engine assemblyThe engine is the source of power that provides thetorque or turning force which is used to drive the

vehicle. Engines in motor vehicles can be internal com-

bustion, electric or a combination of the two (known

as hybrid). Internal combustion engines burn the

fuel inside the engine using petrol, distillate or gas.

Electric motors use electricity supplied from storage

batteries fitted to the vehicle. The batteries can be

charged using an internal combustion engine, fuel cell,

solar cell, power regeneration and external charging.

Figure 1.4 on the following page is a drawing ofa basic engine with its main parts identified. This is a

4 5 6 7 8 9 10 11 12 13

141516171821319

Figure 1.2Skeletal arrangement of a front-wheel-drive vehicle

1 manual transaxle, 2final drive, 3clutch, 4radiator, 5alternator, 6engine assembly, 7front disc brake, 8hub, 9wheel, 10steering assembly,

11 exhaust system, 12rear suspension, 13rear brake, 14fuel tank, 15rear-wheel hub, 16handbrake,17drive shafts, 18suspension,19battery


15/18


3

2 1 1 12 11 10

4 5 6 7 8 9

Figure 1.3Skeletal arrangement of a hybrid-powered vehicle

1 hybrid transaxle, 2electric-motor assembly, 3radiator, 4engine, 5front brake, 6front hub, 7wheel, 8steering assembly, 9fuel line,

10high-voltage battery, 11 fuel tank, 12power cable

camshaft

timing belt

camshaftpulley

cylinder head

piston rings

piston

cylinder

connectingrod

timingpulley

crankshaftpulley

connecting-rodbearing

oil pan

crankshaftmain

bearing

crankshaft

exhaust valve

intake valve

flywheel

Figure 1.4Basic construction of a four-cylinder engine


16/18


four-cylinder petrol engine of the type fitted to pas-

senger cars and light commercial vehicles. More details

of an engine of this type can be seen in Figure 1.5.

In operation, burning fuel inside the cylinders of

the engine produces a high pressure which forces

the pistons to move down their cylinders. Pistonmovement is transferred to the crankshaft by the

connecting rods, causing the crankshaft to rotate.

This rotary motion is then carried by the drive train

to the driving wheels and used to propel the vehicle

along the road.

The engine assembly includes the engine itself

as well as all the components and systems needed

to make it start and run. These include the starting,

charging, cooling, ignition, lubrication, fuel and the

exhaust systems.

Vehicle constructionPassenger cars have a body of unitised construction.

Reinforced panels and subframes are built into the

body to provide the necessary strength and stiffness.A body of this type is shown in Figure 1.6 on the next

page.

Subframes for supporting the engine and trans-

mission, the front and rear suspensions and other

mechanical parts are built into the reinforced under-

body panels. Strengthened sections of panels are

used for mounting other components.

The subframes provide mountings for the engine,

the transmission, the suspension and the steering. The

engine has rubber mountings to prevent noise and

Figure 1.5Four-cylinder engine, sectional view

1 timing belt, 2camshaft drive pulley, 3camshaft, 4intake valve, 5exhaust valve, 6oil filler cap, 7valve rocker gear, 8cylinder head,

9piston in section, 10cylinder block, 11 cylinder, 12connecting rod, 13flywheel, 14connecting-rod big end and crankshaft, 15oil pan or

sump,16

oil pump intake,17

fan belt,18

pulley on crankshaft,19

oil pump,20

water pump,21

fan MITSUBISHI


17/18


vibration being transmitted to the vehicle body. Rubberbushes between the various parts of the suspension

and the subframe also insulate against the noise and

vibration that originates at the road and tyres.

Some light commercial vehicles are designed with

a cab and chassis. They have a drivers cab of unitised

construction and a frame, or rear chassis, on which a

tray-type body, or a commercial body of some other

design can be built.

Larger commercial vehicles have a full frame

or chassis to which the body, engine, suspension,

steering and other mechanical components are

fitted. The chassis is made of steel channel or boxsection for strength, with the parts being welded or

riveted together. Cross-bracing is provided to make

the frame rigid enough to withstand the shocks,

twists and vibrations that it will be subjected to during

operation.

The drive trainThe drive train, also called the power train, includes

all the components that carry drive from the engine

to the driving wheels of the vehicle. Different

arrangements are used for rear-wheel drive and front-

wheel drive (refer to Figures 1.1 and 1.2).

With rear-wheel drive, the drive reaches the rear

wheels through the clutch, transmission, propeller

shaft, final drive, differential and rear axle.

With front-wheel drive, the drive is carried by the

clutch, transaxle and drive shafts to the front wheels

of the vehicle. There are similar components, but

they are arranged differently and are more compact.

Vehicles with automatic transmissions have similar

drive trains to those with manual transmissions,but they have a torque converter instead of a clutch.

Automatic transmissions for front-wheel drive areknown as automatic transaxles.

Handy hint:The term driveis one that is commonly

used, although what is actually being transmitted is

torque, or twisting force.

Clutch

The clutch is a friction-type coupling that enablesthe engine to be connected or disconnected from

the transmission. It consists basically of a large disc

held against the engines flywheel by spring force.

The disc is released by the driver pressing down the

clutch pedal. This allows the gears to be engaged and

gearshifts to be made. The clutch also enables the

load to be applied gradually when starting the vehicle

from rest.

A simplified clutch arrangement is shown in

Figure 1.7. The clutch disc is normally held against

the face of the flywheel by the diaphragm spring,

but is released by the movement of the pedal being

transferred through the cable to the release fork.

A mechanically operated clutch is shown. Its

operation depends on the action of levers. Other

clutches are operated hydraulically.

Rear-wheel drive

In rear-wheel-drive vehicles, a drive shaft, called the

propeller shaft, carries the drive from the transmission

to the rear-axle assembly. It has universal joints and

a sliding spline which allows the shaft to change its

length and angle so that it can adjust to rear-axleand suspension movement.

Figure 1.6Body structure with different metals used. These provide light weight and strength COPYRIGHT HOLDEN 2008. USEDWITHPERMISSION.

Body structure

steel usage

Materials

Low carbon

Medium strengthHigh strength

Advanced high strength

Ultra strength

Aluminium


18/18


Names of componentsand parts

For identification purposes, all the parts of motor vehicles have names, and replacement parts also

have part numbers.

The names are given for various reasons. Some

names relate to the location of the part, and the

word upperorlower is often used in conjunction

with the part name. Other part names include the

words leftorright, orfrontorrear. Examples of this

are upper radiator hose and right front wheel.

Some parts are obviously named according

to their function, such as filter, spring orshock

absorber.

The connection of some other parts withtheir names is a little harder to find, as they can

relate to the name of a person. For example, the

dieselengine takes its name from Dr Diesel, who

developed the engine.

Names of components and parts can vary

from country to country, as can the spelling. For

example, clutch disc can be spelt disc ordisk.

However, with a little thought, the reason for

the names which have been given to various

parts can be understood. This will also assist in

remembering their names.

Larger components

Larger components consist of a number of

small parts: for example, the gearbox can be

considered as a component and the gears

which are fitted inside the gearbox as parts.

Many components that contain other parts are

referred to as housings orboxes, such as the

clutch housingandgearbox.

In other cases, parts can be considered to

form a system, which consists of a number of

components or parts; for example, the fuel

system includes the fuel tank, fuel pump, fuel

lines and fuel injection components.

The diagrams in Figures 1.1 and 1.2 show the

components in simple form and enable various

components which make up the mechanical

section of a motor vehicle to be identified.

Handy hint:The terms components,

parts, units and items are all used in

relation to motor vehicle parts.

Technical termsMotor vehicle, front-wheel drive, rear-wheel drive, four-

wheel drive, all-wheel drive, internal combustion, diesel,

unitised, subframe, chassis, cross bracing, suspension,

drive, drive train, power train, clutch, hydraulic,transmission, gear, gear ratio, manual transmission,

housing, automatic transmission, torque converter, disc

brake, drum brake, rack, pinion, worm, starter, alternator,

electronic, electronic control unit, component, safety

glass, body panels, body hardware, laminated, trim,

mouldings, anticorrosive.

Review questions1. Name the main sections of a motor vehicle.

2. Why is the engine referred to as aninternal-combustion engine?

3. What types of fuel are used in automotive engines?

4. What is the purpose of the shock absorbers?

5. Why are tyres necessary?

6. What are the parts of the power train?

7. Why is a clutch necessary?

8. Why is a transmission fitted to a vehicle?

9. What is a transaxle?

10. What is the function of the universal joints?

11. What does the differential do?

12. What are the two designs of brakes?

13. What is the purpose of the suspension?14. Name some of the parts in a rear-axle assembly.

15. Name some of the electrical parts of a vehicle.

16. How is the alternator driven?

17. What are the main differences between a front-

wheel-drive and a rear-wheel-drive vehicle?

18. Name the main body parts of a passenger car. Refer

to the appropriate illustration.

book1 sample chapter=mach-comp'nt

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