1983 FIAT UNO timing belt

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)

Routine maintenance0•11
Engine compartment (air cleaner removed for clarity) on 55S model
1 Strut upper mounting
2 Washer fluid reservoir
3 Brake fluid reservoir
4 Ignition coil5 Throttle cable
6 Carburettor
7 Battery
8 Timing belt cover9 Distributor
10 Oil filler cap
11 Radiator electric cooling
fan12 Radiator
13 Coolant expansion tank
14 Front mounting
15 Clutch operating cable

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

Auxiliary shaft
Bearing internal diameter (reamed):
No. 1 (timing belt end) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35.664 to 35.684 mm (1.4052 to 1.4059 in)
No. 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32.000 to 32.020 mm (1.2608 to 1.2616 in)
Shaft journal diameter:
No. 1 (timing belt end) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35.593 to 35.618 mm (1.4024 to 1.4033 in)
No. 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.940 to 31.960 mm (1.2584 to 1.2592 in)
Cylinder block and crankcase
Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cast-iron
Bore diameter:
1116 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80.000 to 80.050 mm (3.152 to 3.154 in)
1301 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.400 to 86.450 mm (3.404 to 3.406 in)
Maximum cylinder bore taper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.015 mm (0.0006 in)
Maximum cylinder bore ovality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.015 mm (0.0006 in)
Torque wrench settingsNm lbf ft
Cylinder head bolts:
Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15
Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 30
Stage 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Turn through 90º Turn through 90º
Stage 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Turn through 90º Turn through 90º
Camshaft carrier to cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15
Main bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 59
Big-end cap nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 38
Flywheel mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 61
Camshaft sprocket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 61
Belt tensioner bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 32
Exhaust manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 21
Auxiliary shaft sprocket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 61
Flexible mounting bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 44
Flexible mounting centre nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Oil pressure switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 24
Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Roadwheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 63
Driveshaft/hub nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272 200
Tie-rod end balljoint nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 25
Brake caliper mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 39
Front strut lower clamp bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Driveshaft inboard boot retainer bolts . . . . . . . . . . . . . . . . . . . . . . . . . . 9 7
Crankshaft pulley nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 7
1•6 Engine – general
Part 1: General
1 Description
1The Uno may be powered by one of three
engines depending upon the particular model.
903 cc
2This is of four cylinder overhead valve type
with a light alloy cylinder head and a cast-iron
block and crankcase.
3A three bearing crankshaft is used and the
chain-driven camshaft runs in three steel
backed white metal bearings.
4The light alloy pistons are fitted with two
compression and one oil control ring. The
gudgeon pin is an interference fit in the small
end of the connecting rod.
5Lubrication is provided by an oil pump
within the sump pan and both the pump and
the distributor are driven from a gear on the
camshaft. Pressurised oil passes through acartridge type oil filter. An oil pressure relief
valve is incorporated in the oil pump. The
engine oil is independent of the transmission
lubricant.
1116 cc and 1301 cc
6These engines are of single overhead
camshaft type, the camshaft being driven by a
toothed belt.
7The difference in engine capacity is
achieved by increasing the cylinder bore on
the 1301 cc engine.
8The cylinder head is of light alloy while the
cylinder block and crankcase are of cast-iron
construction.
9A five bearing crankshaft is used and the
camshaft runs in a similar number of bearings,
but as these are in-line bored directly in the
camshaft carrier, no repair is possible.
10The pistons are of light alloy with two
compression and one oil control ring. The
gudgeon pin is an interference fit in the small
end of the connecting rod.
11An auxiliary shaft, driven by the timing belt
is used to drive the distributor, oil pump and
fuel pump.12The oil pump is located within the sump
pan and incorporates a pressure relief valve.
13Pressurised oil passes through a cartridge
type oil filter.
14The crankshaft main bearings are
supplied under pressure from drillings in the
crankcase from the main oil gallery whilst the
connecting rod big-end bearings are
lubricated from the main bearings by oil
forced through the crankshaft oilways. The
camshaft bearings are fed from a drilling from
the main oil gallery. The cams and tappets are
lubricated by oil mist from outlets in the
camshaft bearings.
15The cylinder walls, pistons and gudgeon
pins are lubricated by oil splashed up by the
crankshaft webs. An oil pressure warning light
is fitted to indicate when the pressure is too
low.
All engines
16The engine is mounted transversely with
the transmission at the front of the car.
17The engine oil is independent of the
transmission lubricant.

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.

13Engage the timing chain with the teeth of
the crankshaft sprocket. Then locate the
camshaft sprocket within the upper loop of
the chain in such a way that when the
sprocket is pushed onto the camshaft, the
timing marks will be in alignment. Make sure
that the self-tensioning links are on the inside
of the chain against the cylinder block
(photos).
14Place the camshaft sprocket onto the
camshaft so that its positioning dowel
engages.
15Secure the camshaft sprocket by fitting
the special cam, that drives the fuel pump, on
its locating dowel. Fit the camshaft sprocket
retaining bolt (photo).
16Tighten the sprocket bolt to the specified
torque.
17If the timing cover oil seal showed signs of
leaking before engine overhaul the old seal
should be removed and a new one fitted.
18Using a screwdriver, carefully remove the
old oil seal, working from the rear of the cover.
Fit the new seal making sure it is inserted
squarely, and tap home with a hammer.
19Lubricate the oil seal with engine oil.
20With all traces of old gasket and jointing
compound removed from the timing cover
and cylinder block mating faces, smear a little
grease onto the timing cover mating face and
fit a new gasket in position.
21Fit the timing cover to the cylinder block
and finger tighten the securing bolts, and
spring washer. Ensure that the fuel pump
pushrod bush is in place in the cover.22Wipe the hub of the pulley and carefully
place into position on the crankshaft. It should
locate on the Woodruff key. It may be
necessary to adjust the position of the timing
cover slightly in order to centralise the oil seal
relative to the pulley hub.
23Tighten the timing cover securing bolts in
a diagonal and progressive manner.
24Tighten the crankshaft pulley nut to the
specified torque again holding the crankshaft
against rotation as previously described
(paragraph 2) this Section.
25Refit the fuel pump and alternator
drivebelt.
7 Cylinder head-
removal and refitting
3
1For safety reasons, disconnect the battery
negative lead.
2Refer to Chapter 2 and drain the cooling
system.
3Refer to Chapter 3 and remove the
carburettor, air cleaner and spacer block.
4Undo and remove the five nuts and
washers securing the exhaust manifold and
hot air ducting to the cylinder head.
5Detach the cable from the temperature
indicator sender unit.
6Refer to Chapter 4 and disconnect the
distributor LT lead and the coil HT lead.
7Refer to Chapter 2 and remove the
thermostat housing from the cylinder head.
8Disconnect the coolant hoses from the
cylinder head.
9Note the electrical connections to the rear
of the alternator and disconnect them.
10Disconnect the mounting and adjuster link
bolts and remove the alternator from the
engine.
11Unscrew the four nuts securing the rocker
cover to the top of the cylinder head and lift
away the spring washers and metal packing
pieces. Remove the rocker cover and cork
gasket.
12Unscrew the four rocker pedestal
securing nuts in a progressive manner. Lift
away the four nuts and spring washers andease the valve rocker assembly from the
cylinder head studs.
13Remove the pushrods, keeping them in
the relative order in which they were removed.
The easiest way to do this is to push them
through a sheet of thick paper or thin card in
the correct sequence.
14Unscrew the cylinder head securing bolts
half a turn at a time in the reverse order to that
shown in Fig. 1.7; don’t forget the one within
the inlet manifold. When all the bolts are no
longer under tension they may be unscrewed
from the cylinder head one at a time. This will
also release a section of the cooling system
pipe secured by two of the bolts. All the bolts
have washers.
15The cylinder head may now be lifted off. If
the head is jammed, try to rock it to break the
seal. Under no circumstances try to prise it
apart from the cylinder block with a
screwdriver or cold chisel as damage may be
done to the faces of the head or block. If this
or the Hint, fail to work, strike the head
sharply with a plastic headed hammer, or with
a wooden hammer, or with a metal hammer
with an interposed piece of wood to cushion
the blows. Under no circumstances hit the
head directly with a metal hammer as this may
cause the casting to fracture. Several sharp
taps with the hammer, at the same time
pulling upwards, should free the head. Lift the
head off and place on one side.
16The cylinder head may now be de-
carbonised or dismantled, refer to Section 17.
Refitting
17After checking that both the cylinder block
and cylinder head mating surfaces are
perfectly clean, generously lubricate each
cylinder with engine oil.
18Always use a new cylinder head gasket as
the old gasket will be compressed and not
capable of giving a good seal.
1•10 903 cc engine
6.15 Fitting fuel pump drive cam and
sprocket bolt
6.13C Self-tensioning links on inside of
chain6.13B Timing mark alignment6.13A Fitting the sprockets and timing
chain
If the head will not readily
free, turn the crankshaft.
The compression generated
in the cylinders will often
break the gasket joint

17Screw in the camshaft front bearing
lockscrew (photo).
Oil pump
18Refit the oil pump as described in Sec-
tion 10.
Timing chain and sprockets
19Fit the timing chain and sprockets as
described in Section 6. Fit the Woodruff key
to the crankshaft nose.
20Using a new gasket, fit the timing chain
cover, but leave the bolts finger tight (photo).
21Apply grease to the lips of the timing
cover oil seal and then push the crankshaft
pulley into position.
22Move the timing cover if necessary so that
the pulley hub is centralised in the oil seal and
then tighten the cover bolts.
23Screw on the crankshaft pulley nut and
tighten to the specified torque (photo).
Piston/connecting rods
24Fit these as described in Section 9.
Sump pan
25Fit the sump pan as described in Sec-
tion 8.
Cylinder head
26Stand the engine upright and fit the
cylinder head as described in Section 7.
27Insert the pushrods in their original fitted
order.
28With the rocker arm adjuster screws fully
unscrewed, locate the rocker gear and screw
on the fixing nuts.
29Adjust the valve clearances as described
in Section 5.
30Locate a new gasket in position and fit the
rocker cover (photo).
31Screw on a new oil filter (Section 2).
21 Engine- refitting ancillary
components
1Refer to Chapter 5 and refit the clutch,
making sure to centralise the driven plate.
2Fit the coolant pump as described in
Chapter 2. Fit the thermostat housing if it was
removed noting the air cleaner mounting
bracket on the housing studs.
3Fit the alternator and drivebelt as described
in Chapter 9.
4Refer to Chapter 3 and fit the exhaust
manifold and hot air collector, the carburettor
and spacer and the fuel pump.
5Fit the distributor as described in Chapter
4. Fit the oil dipstick guide tube (photos).
22 Engine/transmission-
reconnection
1
1Support the weight of the transmission and
offer it squarely to the engine. The splined
input shaft should pass easily through the hub
of the driven plate, provided the plate has
been centralised as described in Chapter 5. It
may be necessary to align the splines with the
hub grooves, in which case have an assistant
turn the crankshaft pulley nut. The alignment
dowels will make the connection stiff, so
drawing the engine and transmission together
with two connecting bolts will ease it.
2Once the engine and transmission are fully
engaged, insert and tighten all the connecting
bolts. Locate the lifting eyes.
3Bolt on the flywheel housing cover plate
and the mounting brackets.
4Bolt on the starter motor.
23 Engine/transmission-
refitting
3
1The refitting operations are reversals of
those described in Section 13.
2Observe the following special points.
3Tighten the engine mounting and front
suspension (disconnected) bolts to the
specified torque when the hoist has been
1•22 903 cc engine
21.5B Dipstick guide tube support21.5A Dipstick guide tube20.30 Rocker cover nut and thrust plate
20.23 Tightening crankshaft pulley nut20.20 Timing cover20.17 Camshaft front bearing lockscrew
Hold the crankshaft against
rotation either by jamming
the starter ring gear or by
placing a block of wood
between a crankshaft web and the
inside of the crankcase.

removed and the weight of the car is again on
its roadwheels.
4Fill the cooling system.
5Fill the engine with oil.
6Replenish lost transmission oil.
7Reconnect the battery.
8Adjust the clutch pedal as described in
Chapter 5.
24 Engine- initial start-up after
overhaul or major repair
4
1Make sure that the battery is fully charged
and that all lubricants, coolant and fuel are
replenished.
2If the fuel system has been dismantled it will
require several revolutions of the engine on
the starter motor to pump the petrol up to the
carburettor.
3Turn the carburettor throttle speed screwthrough one complete turn to increase the idle
speed in order to offset the initial stiffness of
new engine internal components.
4As soon as the engine fires and runs, keep
it going at a fast idle speed and bring it up to
normal working temperature.
5As the engine warms up there will be odd
smells and some smoke from parts getting
hot and burning off oil deposits. The signs to
look for are leaks of water or oil which will be
obvious.
6Check also the exhaust pipe and manifold
connections as these do not always “find”
their exact gas tight position until the warmth
and vibration have acted on them and it is
almost certain that they will need tightening
further. This should be done, of course, with
the engine stopped.
7When normal running temperature has
been reached, adjust the engine idle speed as
described in Chapter 3.
8Stop the engine and wait a few minutes tosee if any lubricant or coolant is dripping out
when the engine is stationary.
9Road test the car to check that the timing is
correct and that the engine is giving the
necessary smoothness and power. Do not
race the engine - if new bearings and/or
pistons have been fitted it should be treated
as a new engine and run in at a reduced
speed for the first 500 km (300 miles).
10After the first 1500 km (900 miles) the
cylinder head bolts must be re-torqued in the
following way (engine cold).
11Remove the air cleaner and rocker cover.
Unscrew the first bolt (Fig. 1.7) through a
quarter turn and then tighten it to final stage 2
torque (see Specifications).
12Repeat on the remaining bolts, one at a
time.
13Check and adjust the valve clearances
(Section 5).
14Refit the rocker cover and air cleaner.
903 cc engine 1•23
26.4 Shim engraved mark26.2 Removing a shim from a cam follower25.4 Checking a valve clearance
1
Part 3: 1116 cc and 1301 cc engines
25 Valve clearances- checking
2
This should only be required if the valves
have been renewed or ground in, or at high
mileages when noise or poor engine
performance indicates that a check is
necessary.
It is important that each valve clearance is
set correct otherwise the timing will be
wrong and engine performance poor. If there
is no clearance at all, the valve and its seat
will soon burn. Always set the clearances
with the engine cold.
1Remove the camshaft cover. Jack-up a
front wheel and engage top gear so that by
turning the wheel, the crankshaft can be
rotated.
2Each valve clearance must be checked
when the high point of the cam is pointing
directly upward away from the cam follower.
3Check the clearances in the firing order
1-3-4-2, No. 1 cylinder being at the timing
belt end of the engine. This will minimise the
amount of crankshaft rotation required.4Insert the appropriate feeler blade
between the heel of the cam and the cam
follower shim of the first valve. If necessary
alter the thickness of the feeler blade until it
is a stiff, sliding fit. Record the thickness,
which will, of course, represent the valve
clearance for this particular valve (photo).
5Turn the crankshaft, check the second
valve clearance and record it.
6Repeat the operations on all the remaining
valves, recording their respective clearances.
7Remember that the clearance for inlet and
exhaust valves differs - see Specifications.
Counting from the timing cover end of the
engine, the valve sequence is:
Inlet 2-3-6-7
Exhaust 1-4-5-8
26 Valve clearances-
adjustment
3
1Check the valve clearances (Section 25).
2Clearances which are incorrect will mean
the particular shim will have to be changed.
To remove the shim, turn the crankshaft untilthe high point of the cam is pointing directly
upward. The cam follower will now have to
be depressed so that the shim can be
extracted. Special tools (A60642 and
A87001) are available from your Fiat dealer to
do the job, otherwise you will have to make
up a forked lever to locate on the rim of the
cam follower. This must allow room for the
shim to be prised out by means of the
cut-outs provided in the cam follower rim
(photo).
3Once the shim is extracted, establish its
thickness and change it for a thicker or
thinner one to bring the previously recorded
clearance within specification. For example,
if the measured valve clearance was 1.27
mm (0.05 in) too great, a shim thicker by this
amount will be required. Conversely, if the
clearance was 1.27 mm (0.05 in) too small, a
shim thinner by this amount will be required.
4Shims have their thickness (mm) engraved
on them; although the engraved side should
be fitted so as not to be visible, wear still
occurs and often obliterates the number. In
this case, measuring their thickness with a
metric micrometer is the only method to
establish their thickness (photo).