1983 FIAT UNO oil change

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•6General dimensions, weights and capacities
Dimensions
Overall length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3644 mm (143.6 in)
Overall width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1555 mm (61.3 in)
Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1432 mm (56.4 in)
Wheelbase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2362 mm (93.1 in)
Front track . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1340 mm (52.8 in)
Rear track . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1300 mm (51.2 in)
Weights (kerb)
Uno 45:
Three-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 700 kg (1543 lb)
Five-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 710 kg (1566 lb)
Uno 55:
Three-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 730 kg (1610 lb)
Five-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 740 kg (1632 lb)
Uno 70:
Three-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 740 kg (1632 lb)
Five-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 750 kg (1654 lb)
Uno SX:
Three-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 770 kg (1698 lb)
Five-door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 780 kg (1720 lb)
Capacities
Fuel tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.0 litre (9.25 gal)
Engine oil (with filter change):
903 cc engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.42 litre (6.0 pint)
1116 and 1301 cc engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.10 Iitre (7.2 pint)
Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.40 litre (4.2 pint)
Steering box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140.0 cc
Driveshaft CV joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125.0 cc
Cooling system:
903 cc engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6 litre (8.1 pint)
1116 cc engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.0 litre (10.6 pint)
1301 cc engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2 litre (10.9 pint)
For information applicable to later models, see Supplement at end of manual

0•8Roadside Repairs
To avoid repetition, the procedure for
raising the vehicle, in order to carry out work
under it, is not included before each relevant
operation described in this Manual.
It is to be preferred, and it is certainly
recommended, that the vehicle is positioned
over an inspection pit or raised on a lift. Where
these facilities are not available, use ramps or
jack up the vehicle strictly in accordance with
the following guide. Once the vehicle is raised,
supplement the jack with axle stands.
Jacking
The jack supplied with the car should only
be used to change a wheel. Do not use this
jack when overhaul or repair work is being
carried out; employ a hydraulic or screw jack
and supplement it with axle stands.
Jacking points are located under the sills
for use with the jack supplied.To raise the front end with a garage jack,
locate the jack under the transmission lower
mounting, just below and slightly to the rear of
the transmission oil drain plug. Protect the
mounting by placing a block of wood between
the jack head and the mounting.
To raise the rear of the car, the jack should
be placed under the spare wheel housing as
far to the rear as possible. Place a wooden
bearer between the jack head and the
housing.
Towing
When being towed, use the left-hand front
towing eye.
When towing another vehicle, use the rear
towing eye adjacent to the exhaust tailpipe.
When being towed, remember that the
brake pedal will require heavier pressure due
to lack of servo assistance. Always turn theignition key to MAR to retain the steering in
the unlocked position.
Wheel changing
With the car on firm level ground, apply the
handbrake fully. Remove the hub cap or
wheel trim, if fitted.
Release, but do not remove, the bolts.
Chock the front and rear of the opposite
roadwheel and then raise the car using the sill
jack supplied with the car if it is being done at
the roadside. Alternatively use a workshop
jack supplemented with axle stands.
Remove the wheel bolts, change the wheel
and screw in the bolts finger tight. It is
recommended that the bolt threads are
smeared with multi-purpose grease. Lower
the car, remove the jack and tighten the wheel
bolts to the specified torque. Refit any wheel
trim that was removed.
Spare wheel and jack stowage
Front tow hook Rear tow hook
Jacking, towing and wheel changing

Roadside Repairs0•9
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 and
to park it over some clean paper 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.

0•12Routine maintenance
View of front end from below on
55S model
1 Tie-rod end
2 Track control arm
3 Lower mounting
4 Gearchange control rods
5 Exhaust pipe
6 Driveshafts
7 Transmission
8 Sump drain plug
9 Disc caliper
10 Front mounting
11 Horns
12 Radiator
13 Oil filter
View of rear end from below
1 Suspension trailing arm
2 Fuel tank filler hose
3 Rear axle beam
4 Rear silencer
5 Spring seat
6 Expansion box
7 Handbrake cable
8 Fuel tank support strap
9 Fuel tank
10 Handbrake cable adjuster

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

micrometer to trace the cause of the trouble.
It is very seldom that any trouble of this nature
will be experienced when fitting the
crankshaft.
9Tighten the main bearing bolts to the
specified torque wrench settings (photo).
10Using a dial gauge or feeler blades
inserted between a thrust washer and the
crankshaft, check the crankshaft endfloat. If it
exceeds the specified limit, the thrust washers
can be changed for thicker ones (photo).
11Bolt on the crankshaft rear oil seal carrier
using a new gasket. The carrier should have
been fitted with a new oil seal and the seal lips
greased (photos).
12Fit the engine rear plate (photo).
Flywheel
13Offer the flywheel to the crankshaft. With
pistons No. 1 and 4 at TDC, the dimple on the
flywheel must be uppermost.
14Screw in and tighten the bolts to the
specified torque. The crankshaft may be held
against rotation by either jamming the starter
ring gear or placing a block of wood between
one of the crankshaft webs and the inside of
the crankcase (photo).
Camshaft
15Oil the cam followers and return them to
their original positions (photo).
16Oil the camshaft bearings and insert the
camshaft, taking great care not to damage the
bearings with the cam lobes. Fit the front
bearing, chamfer inwards (photos).
903 cc engine 1•21
20.10 Checking crankshaft end float20.9 Tightening main bearing cap bolts20.6 Fitting a main bearing cap
20.16B Camshaft front bearing20.16A Fitting camshaft
20.11B Crankshaft oil seal and carrier
fitted20.11A Crankshaft rear oil seal carrier and
gasket
20.14 Tightening flywheel bolts20.12 Engine rear plate
20.15 Cam followers
1