1983 FIAT UNO check engine

REPAIRS & OVERHAUL
Engine and Associated Systems
Engine (also see Chapter 13)Page 1•1
Cooling and heating systems (also see Chapter 13)Page2•1
Fuel system (also see Chapter 13)Page 3•1
Ignition system (also see Chapter 13)Page4•1
Transmission
Clutch (also see Chapter 13)Page5•1
Transmission (also see Chapter 13)Page6•1
Driveshafts, hubs, roadwheels and tyres (also see Chapter 13)Page7•1
Brakes
Braking system(also see Chapter 13)Page 8•1
Electrical
Electrical system(also see Chapter 13)Page 9•1
Steering and suspension
SteeringPage 10•1
Suspension (also see Chapter 13)Page 11•1
Bodywork
Bodywork (also see Chapter 13)Page 12•1
Additional information
Supplement: Revisions and information on later models Page 13•1
Wiring DiagramsPage 14•1
REFERENCE
MOT Test Checks PageREF•1
Tools and Working Facilities Page REF•5
General Repair Procedures Page REF•8
Fault FindingPage REF•9
Buying Spare Parts & Vehicle Identification Numbers PageREF•12
Glossary of Technical Terms PageREF•13
IndexPage REF•17
Contents

Safety First!0•5
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 high-
torque 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 oil-
soaked 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 400
0C. 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
• 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•10Routine maintenance
Maintenance is essential for ensuring safety and desirable for the
purpose of getting the best in terms of performance and economy
from the car. Over the years the need for periodic lubrication has been
greatly reduced if not totally eliminated. This has unfortunately tended
to lead some owners to think that because no such action is required
the items either no longer exist or will last forever. This is certainly not
the case; it is essential to carry out regular visual examinations as
comprehensively as possible in order to spot any possible defects at
an early stage before they develop into major and expensive repairs.
For information applicable to later models, see Supplement.
Every 250 miles (400 km), weekly,
or before a long journey
m mCheck engine oil level
m mCheck brake reservoir fluid level
m mCheck tyre pressures
m mCheck operation of all lights and horn
m mTop up washer fluid reservoirs, adding a screen
wash, and check operation of washers and wipers
m mCheck coolant level
m mCheck battery electrolyte level
Every 6000 miles (10 000 km)
or six months, whichever comes first
m mRenew engine oil and filter (Chapter 1, Section 2)
m mCheck drivebelt tension (Chapter 2, Section 8)
m mCheck carburettor idle speed and mixture
adjustments (Chapter 3)
m mCheck contact points and dwell angle (mechanical
breaker distributors) (Chapter 4, Section 3)
m mCheck tyre tread wear (Chapter 7, Section 7)
m mCheck disc pads for wear (Chapter 8, Section 3)
Every 36 000 miles (60 000 km)
or three years, whichever comes first
m mRenew the timing belt - 1116 and 1299/1301 cc
(Chapter 1, Section 28)
m mCheck exhaust system for corrosion (Chapter 3,
Section 19)
m mRenew contact breaker points and adjust dwell
angle (mechanical breaker distributors) (Chapter 4,
Section 3)
m mCheck and adjust ignition timing (Chapter 4,
Section 4)
m mRenew spark plugs (Chapter 4, Section 11)
m mCheck clutch adjustment (Chapter 5, Section 2)
m mCheck transmission oil level (Chapter 6, Section 2)
m mCheck driveshaft and steering rack gaiters for splits
(Chapters 7 and 10)
m mCheck rear brake shoe linings for wear (Chapter 8,
Section 4)
m mCheck handbrake travel (Chapter 8, Section 16)
m mCheck headlamp beam alignment (Chapter 9,
Section 17)
m mCheck balljoints for wear (Chapter 10, Section 2)
m mCheck front wheel alignment (Chapter 10, Section 8)
m mCheck suspension bushes for wear (Chapter 11,
Section 2)
m mCheck seat belts for fraying (Chapter 12, Section 23)
m mLubricate controls, hinges and locks
Every 24 000 miles (40 000 km)
or two years, whichever comes first
m mRenew coolant anti-freeze mixture (Chapter 2,
Section 3)
m mRenew transmission oil (Chapter 6, Section 2)
m mRenew brake hydraulic fluid (Chapter 8, Section 12)
m mCheck for underbody corrosion and clean out door
and sill drain holes (Chapter 12, Section 2)
Every 12 000 miles (20 000 km) or
12 months, whichever comes first
m mCheck and adjust valve clearances (Chapter 1,
Sections 5 and 26)
m mRenew air cleaner element (Chapter 3, Section 2)

1
903 cc engine
Type
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Four cylinder in-line, liquid cooled, overhead valve. Transversely
mounted with end-on transmission
General
Bore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65.0 mm (2.56 in)
Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68.0 mm (2.68 in)
Displacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 903 cc (55 cu in)
Compression ratio:
900 models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.0 : 1
900 ES models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.7 : 1
Maximum power (DIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.1 kW at 5600 rev/min (45 bhp)
Maximum torque (DIN):
900 models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 Nm at 3000 rev/min (49 lbf ft)
900 ES models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Nm at 3000 rev/min (51 lbf ft)
Compression pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.3 to 10.35 bar (135 to 150 lbf/in2)
Maximum pressure difference between cylinders . . . . . . . . . . . . . . . . . 0.69 bar (10 lbf/in2)
Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 - 3 - 4 - 2 (No. 1 at crankshaft pulley end)
Chapter 1 Engine
For modifications, and information applicable to later models, see Supplement at end of manual
Part 1: General
Crankcase ventilation system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Engine oil and filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Major operations possible without removing the engine
from the car . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Part 2: 903 cc engine
Cylinder head - dismantling and decarbonising . . . . . . . . . . . . . . . . 17
Cylinder head - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 7
Engine - complete dismantling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Engine - complete reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Engine - dismantling (general) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Engine - initial start-up after overhaul or major repair . . . . . . . . . . . . 24
Engine - method of removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Engine - reassembly (general) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Engine - refitting ancillary components . . . . . . . . . . . . . . . . . . . . . . . 21
Engine - removing ancillary components . . . . . . . . . . . . . . . . . . . . . 15
Engine mountings - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Engine/transmission - reconnection . . . . . . . . . . . . . . . . . . . . . . . . . 22
Engine/transmission - refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Engine/transmission - removal and separation . . . . . . . . . . . . . . . . . 13
Examination and renovation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Fault finding - all engines . . . . . . . . . . . . . . . . . . . . See end of Chapter
Oil pump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Pistons/connecting rods - removal and refitting . . . . . . . . . . . . . . . . 9Sump pan - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Timing chain and sprockets - removal and refitting . . . . . . . . . . . . . 6
Valve clearances - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Part 3: 1116 cc and 1301 cc engines Camshaft and camshaft carrier - removal and refitting . . . . . . . . . . 27
Cylinder head - dismantling and decarbonising . . . . . . . . . . . . . . . . 39
Cylinder head - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . 29
Engine - complete dismantling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Engine - complete reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Engine - dismantling (general) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Engine - initial start-up after major overhaul . . . . . . . . . . . . . . . . . . . 45
Engine - method of removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Engine - reassembly (general) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Engine ancillary components - refitting . . . . . . . . . . . . . . . . . . . . . . . 43
Engine ancillary components - removal . . . . . . . . . . . . . . . . . . . . . . 37
Engine mountings - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Engine/transmission - reconnection and refitting . . . . . . . . . . . . . . . 44
Engine/transmission - removal and separation . . . . . . . . . . . . . . . . . 35
Examination and renovation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Fault finding - all engines . . . . . . . . . . . . . . . . . . . . See end of Chapter
Oil pump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Pistons/connecting rods - removal and refitting . . . . . . . . . . . . . . . . 32
Sump pan - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Timing belt - renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Valve clearances - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Valve clearances - checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
1•1
Specifications Contents
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321

Cylinder head and valves
Material (cylinder head) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Light alloy
Maximum distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 mm (0.002 in)
Valve guide bore in head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.950 to 12.977 mm (0.5099 to 0.5109 in)
Valve guide outside diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.010 to 13.030 mm (0.5122 to 0.5130 in)
Valve guide oversizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5, 0.10, 0.25 mm (0.002, 0.004, 0.010 in)
Inside diameter of valve guide (reamed) . . . . . . . . . . . . . . . . . . . . . . . . . 7.022 to 7.040 mm (0.2765 to 0.2772 in)
Guide fit in head (interference) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.033 to 0.080 mm (0.0013 to 0.0032 in)
Valve stem diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.982 to 7.000 mm (0.2748 to 0.2756 in)
Maximum clearance (valve stem to guide) . . . . . . . . . . . . . . . . . . . . . . . 0.022 to 0.058 mm (0.0009 to 0.0023 in)
Valve seat angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44º 55’ to 45º 05’
Valve face angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45º 25’ to 45º 35’
Valve head diameter:
Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29.0 mm (1.1417 in)
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26.0 mm (1.0236 in)
Contact band (valve to seat) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 to 1.5 mm (0.0512 to 0.0591 in)
Valve clearance:
Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.15 mm (0.006 in)
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.20 mm (0.008 in)
For timing check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.60 mm (0.024 in)
Valve timing:
Inlet valve:
Opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7º BTDC
Closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36º ABDC
Exhaust valve:
Opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38º BBDC
Closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5º ATDC
Lubrication system
Oil pump type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear, driven by shaft from camshaft
Tooth tip to body clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 to 0.14 mm (0.0020 to 0.0055 in)
Gear endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.020 to 0.105 mm (0.0008 to 0.0041 in)
Oil pressure at normal operating temperature and average road/
engine speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.94 to 3.92 bar (42 to 57 lbf/ in
2)
Oil capacity (with filter change) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.42 litre (6.0 pint)
Oil type/specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Multigrade engine oil, viscosity SAE 15W/40
Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion C101
Torque wrench settingsNm lbf ft
Cylinder head bolts:
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 22
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 43.5
Camshaft sprocket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Main bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 51
Big-end bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 30
Crankshaft pulley nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 72
Flywheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 32
Rocker pedestal nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 29
Engine mounting bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Engine mounting centre nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Exhaust manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15
Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Temperature sender switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Driveshaft to hub nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272 200
Hub carrier to strut clamp bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Roadwheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 63
Brake caliper mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 39
Tie-rod end balljoint nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 25
Driveshaft inboard boot retainer bolts . . . . . . . . . . . . . . . . . . . . . . . . . . 9 7
Engine – general 1•3
1

Crankshaft
Journal diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50.785 to 50.805 mm (1.9994 to 2.0002 in)
Standard main bearing shell thickness . . . . . . . . . . . . . . . . . . . . . . . . . . 1.825 to 1.831 mm (0.0719 to 0.0721 in)
Undersizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.254, 0.508, 0.762, 1.016 mm (0.010. 0.020, 0.030, 0.040 in)
Crankshaft endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.06 to 0.26 mm (0.0024 to 0.0102 in)
Crankpin diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45.498 to 45.518 mm (1.7926 to 1.7934 in)
Standard big-end shell bearing thickness . . . . . . . . . . . . . . . . . . . . . . . 1.531 to 1.538 mm (0.0603 to 0.0606 in)
Undersizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.254, 0.508, 0.762, 1.016 mm (0.010, 0.020, 0.030, 0.040 in)
Camshaft
Number of bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Diameter of camshaft journals:
No. 1 (timing end) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29.944 to 29.960 mm (1.1798 to 1.1804 in)
No. 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47.935 to 47.950 mm (1.8886 to 1.8892 in)
No. 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48.135 to 48.150 mm (1.8965 to 1.8971 in)
No. 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48.335 to 48.350 mm (1.9044 to 1.9050 in)
No. 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48.535 to 48.550 mm (1.9122 to 1.9129 in)
Cam lift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.8 mm (0.3467 in)
Camshaft bearing diameters in carrier:
No. 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29.990 to 30.014 mm (1.1816 to 1.1825 in)
No. 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47.980 to 48.005 mm (1.8904 to 1.8913 in)
No. 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48.180 to 48.205 mm (1.8982 to 1.8992 in)
No. 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48.380 to 48.405 mm (1.9062 to 1.9072 in)
No. 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48.580 to 48.605 mm (1.9141 to 1.9150 in)
Outside diameter of cam follower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36.975 to 36.995 mm (1.4568 to 1.4576 in)
Cam follower running clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.005 to 0.050 mm (0.0002 to 0.0020 in)
Lubrication system
Oil pump type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear driven from auxiliary shaft
Tooth tip to body clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.110 to 0.180 mm (0.0043 to 0.0071 in)
Gear endfloat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.020 to 0.105 mm (0.0008 to 0.0041 in)
Oil pressure at normal operating temperature and average road/
engine speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.43 to 4.9 bar (50 to 71 lbf/in
2)
Oil capacity (with filter change) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.05 litre (7.1 pint)
Oil type/specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Multigrade engine oil, viscosity SAE 15W/40
Oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion C106
Cylinder head and valves
Head material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Light alloy
Maximum distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 mm (0.002 in)
Valve guide bore in head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.950 to 13.977 mm (0.5496 to 0.5507 in)
Valve guide outside diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.040 to 14.058 mm (0.5532 to 0.5539 in)
Valve guide oversizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05, 0.10, 0.25 mm (0.002, 0.004, 0.010 in)
Inside diameter of valve guide (reamed) . . . . . . . . . . . . . . . . . . . . . . . . . 8.022 to 8.040 mm (0.3161 to 0.3168 in)
Valve guide fit in cylinder head (interference) . . . . . . . . . . . . . . . . . . . . . 0.063 to 0.108 mm (0.0025 to 0.0043 in)
Valve stem diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.974 to 7.992 mm (0.3142 to 0.3149 in)
Maximum clearance (valve stem to guide) . . . . . . . . . . . . . . . . . . . . . . . 0.030 to 0.066 mm (0.0012 to 0.0026 in)
Valve face angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45º 25’ to 45º 35’
Valve seat angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44º 55’ to 45º 05’
Valve head diameter:
Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35.850 to 36.150 mm (1.4125 to 1.4243 in)
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30.850 to 31.450 mm (1.2155 to 1.2391 in)
Contact band (valve to seat) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 to 1.5 mm (0.0512 to 0.0591 in)
Valve clearance:
Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.40 mm (0.0158 in)
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.50 mm (0.0197 in)
For timing check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.80 mm (0.0315 in)
Valve clearance adjusting shim thicknesses . . . . . . . . . . . . . . . . . . . . . 3.25 to 4.70 mm (0.128 to 0.185 in), in increments of 0.05 mm
(0.002 in)
Valve timing:
Inlet valve:
Opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7º BTDC
Closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35º ABDC
Exhaust valve:
Opens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37º BBDC
Closes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5º ATDC
Engine – general 1•5
1

2 Engine oil and filter
1
1The engine oil level should be checked at
the weekly service (see “Routine
Maintenance”). Preferably check the level
cold, first thing in the morning or if the engine
has been running, allow at least ten minutes
to elapse after switching off to permit the oil to
drain.
2Withdraw the dipstick, wipe it clean on
non-fluffy material, re-insert it and then
withdraw it for the second time (photo).
3The oil level should be between the MIN
and MAX marks. If not, top up with specified
oil to the MAX mark. Pour the oil slowlythrough the filler orifice on the rocker cover.
To raise the oil level from MIN to MAX will
require approximately 1.1 litre (2.0 pints)
(photos).
4At the intervals specified in “Routine
Maintenance” the oil and filter should be
renewed.
5Have the engine at normal operating
temperature, remove the oil filler cap.
6Place a suitable container under the sump
pan. Unscrew and remove the oil drain plug
and allow the oil to drain (photo).
7While the oil is draining, unscrew and
discard the oil filter. To unscrew the filter, a
filter or chain wrench will normally be
required. If such a tool is not available, drive a
long screwdriver through the oil tester casing
and use it as a lever to unscrew the filter
cartridge.
8Smear the rubber sealing ring of the new oil
filter with oil and screw into position using
hand pressure only (photo).
9Refit the drain plug and refill the engine with
the correct quantity and grade of oil.
10Start the engine. It will take two or three
seconds for the oil warning lamp to go out.
This is normal and is due to the time taken for
the new filter to fill with oil.
11Switch off, check for leaks and check the
oil level, topping up if necessary.
3 Crankcase ventilation
system
1
1This system is designed to draw oil fumes
and blow-by gas (which has passed the piston
rings) from the crankcase and draw it into the
intake manifold when it will then be burned
during the normal combustion process.
2Regularly check the security of the system
hoses which run from the rocker cover or
crankcase breather unit (photo).
3Periodically, detach the hoses and clean
them out with paraffin and a brush or rag pull
through.
4Evidence of sludge or emulsified oil within
the hoses or inside the oil filler cap will
indicate that the engine is running too cool
particularly if the car is used mainly for short
journeys where the engine never reaches full
working temperature.
4 Major operations possible
without removing engine
from car
1The following work can be carried out without
the need to remove the engine from the car.
903 cc engine
Valve clearances - checking and adjusting
Timing chain and sprockets - removal and
refitting
1•8 Engine – general
3.2 Crankcase vent hose (1116 cc)Fig. 1.5 Sectional view of oil filter. Bypass
valve arrowed (Sec 2)2.8 Screwing on the oil filter (903 cc)
2.6 Engine sump drain plug
2.3B Topping up engine oil (1116 cc)2.3A Typical dipstick markings2.2 Withdrawing engine oil dipstick
(1116 cc)

Cylinder head - removal and refitting
Sump pan - removal and refitting
Pistons/connecting rods - removal and
refitting
Oil pump - removal and refitting
Engine mountings - renewal
1116 cc and 1301 cc engines
Valve clearances - checking and adjusting
Camshaft and camshaft carrier - removal
and refitting
Timing belt - removal and refitting
Cylinder head - removal and refitting
Sump pan - removal and refitting
Oil pump - removal and refitting
Pistons/connecting rods - removal and
refitting
Engine mountings - renewal
Part 2:
903 cc engine
5 Valve clearances-
adjustment
2
1Adjust the valves when the engine is cold.
2Unbolt and remove the rocker cover.
3It is important that the clearance is set
when the cam follower of the valve being
adjusted is on the heel of the cam (ie;
opposite the peak). This can be done by
carrying out the adjustments in the following
order, which also avoids turning the
crankshaft more than necessary.
4Turn the crankshaft either using a spanner
on the pulley nut or by raising a front
roadwheel, engaging a gear (3rd or 4th) and
turning the wheel in the forward direction of
travel. It will be easier to turn the engine if the
spark plugs are first removed.
Valve fully open Check and adjust
Valve No. 8 EX Valve No. 1 EX
Valve No. 6 IN Valve No. 3 IN
Valve No. 4 EX Valve No. 5 EX
Valve No. 7 IN Valve No. 2 IN
Valve No. 1 EX Valve No. 8 EX
Valve No. 3 IN Valve No. 6 IN
Valve No. 5 EX Valve No. 4 EX
Valve No. 2 IN Valve No. 7 IN5Count the valves from the timing cover end
of the engine.
6Remember, the inlet and exhaust valve
clearances are different.
7Insert the appropriate feeler gauge between
the end of the valve stem and the rocker arm.
It should be a stiff sliding fit (photo).
8If the clearance is incorrect, release the
rocker arm adjuster screw locknut using a ring
spanner. Turn the adjuster screw using a
small open-ended spanner, but tie something
to it in case it is inadvertently dropped
through one of the pushrod holes.
9Once the clearance is correct, tighten the
locknut without moving the position of the
adjuster screw.
10Repeat the operations on the remaining
seven valves.
11Re-check all the clearances. Make sure
that the rocker cover gasket is in good
condition and fit the rocker cover.
6 Timing chain and sprockets
- removal and refitting
3
1Remove the alternator drivebelt as
described in Chapter 2.
2Unscrew and remove the crankshaft pulley
nut.3Disconnect the hoses from the fuel pump.
4Unbolt and remove the fuel pump with
spacer and rod.
5Support the engine on a hoist or under the
sump and disconnect and remove the
right-hand mounting. Then unscrew and
remove the timing cover bolts. The base of
the cover is secured by the front two sump
pan studs. Unbolt and lower the front end of
the sump. Avoid breaking the gasket. Remove
the timing cover.
6Undo and remove the camshaft sprocket
securing bolt; this will also release the fuel
pump drive cam from the end of the camshaft.
Note the timing marks on the camshaft and
crankshaft sprockets.
7Using two tyre levers, carefully ease the two
sprockets forwards away from the crankcase.
Lift away the two sprockets and timing chain.
8Remove the Woodruff key from the
crankshaft nose with a pair of pliers and note
how the channel in the pulley is designed to fit
over it. Place the Woodruff key in a container
as it is a very small part and can easily
become lost. The camshaft sprocket is
located on the camshaft by a dowel peg.Refitting
9Fit the Woodruff key to the front of the
crankshaft.
10Tap the crankshaft sprocket onto the front
of the crankshaft.
11Turn the sprocket so that the Woodruff
key is uppermost.
12Turn the camshaft until it is in such a
position that if the sprocket was fitted the
dimple timing mark on the sprocket would be
nearest to and in alignment with, the one on
the crankshaft sprocket.
903 cc engine 1•9
5.7 Adjusting a valve clearance
1 Sprocket retaining bolt
2 Fuel pump eccentric cam
3 Timing chain4 Camshaft sprocket
5 Sprocket locating dowel
6 Camshaft7 Woodruff key
8 Crankshaft
9 Crankshaft sprocket
Fig. 1.6 Timing chain and sprockets (Sec 6)
1
To prevent the crankshaft
rotating, either select a gear
and have an assistant apply
the footbrake hard or
remove the starter motor and lock the
ring gear teeth with a large cold chisel
or screwdriver.