coolant FIAT UNO 1983 Service User Guide

8Fit the new belt. Start at the crankshaft
drive pulley and, taking care not to kink or
strain the belt, slip it over the camshaft pulley.
The camshaft may have to be turned slightly
to mesh the pulley with the teeth on the belt.
Fit the belt on the tensioner pulley last; if this
is difficult, do not lever or force the belt on,
recheck the belt (photo).
9Release the tensioner nut and rotate the
crankshaft through two complete revolutions.
Retighten the nut. The belt tension may be
checked by twisting it through 90º with the
finger and thumb. It should just turn through
this angle without undue force. Note: The
above procedure serves only as a rough guide
to setting the belt tension - having it checked
by a FIAT dealer at the earliest opportunity is
recommended.
10Refit the timing belt cover (photo). Fit and
tension the alternator drivebelt (Chapter 2,
Section 8).
29 Cylinder head-
removal and refitting
3
1Drain the cooling system (see Chapter 2).
2Disconnect the battery.
3Disconnect and plug the carburettor fuel
hoses.
4Disconnect the throttle and choke linkage
from the carburettor. 5Disconnect the HT leads from the spark
plugs.
6Disconnect the brake servo vacuum hose
from the intake manifold.
7Disconnect the coolant hoses from the
thermostat housing.
8Disconnect the crankcase ventilation
system hoses from the rocker cover and
carburettor.
9Unbolt and remove the timing belt cover.
10Release the timing belt tensioner pulley
bolt, then lever the pulley against the spring
plunger and retighten the bolt to retain the
tensioner pulley in the non-tensioned position.
Slip the belt from the camshaft sprocket.
11Disconnect the coolant hoses from the
carburettor and intake manifold.
12Disconnect the exhaust downpipes from
the manifold.
13If a crowfoot type wrench is available, the
cylinder head nuts and bolts can be removed
and the complete cylinder head camshaft
carrier assembly withdrawn (photo).
14If this type of wrench is not available
however, remove the carrier first as described
in Section 27.
15If a crowfoot is available, unscrew the
cylinder head nuts and bolts evenly and
progressively starting with the centre ones
and working towards both ends.
16Rock the cylinder head by gripping the
manifolds. Note: Do not insert a lever in
the gasket joint to prise the head from the
block.17Pull the head off the studs and remove it
to the bench. Remove and discard the old
cylinder head gasket.
18Unbolt and remove the hot air collecting
shield for the air cleaner from the exhaust
manifold. The exhaust and inlet manifolds can
now be unbolted. The carburettor may remain
on the inlet manifold.
19Overhaul and decarbonising of the
cylinder head is described in Section 39.
20Refitting is a reversal of the removal
process, but make sure the crankshaft and
camshaft timing marks are set as described in
Section 28 to avoid the valve heads digging
into the piston crowns when the head is
refitted.
21Always use new gaskets. The cylinder
1116 cc and 1301 cc engine 1•25
Fig. 1.29 Timing belt arrangement (Sec 28)
1 Camshaft sprocket
2 Tensioner pulley locknut
3 Timing mark on crankshaft front oil seal
retainer
4 Crankshaft sprocket
5 Crankshaft sprocket timing mark
6 Auxiliary shaft sprocket
7 Tensioner bracket bolt
8 Tensioner pulley
9 Timing belt
10 Tensioner bracket
11 Tensioner spring
28.8 Slipping timing belt onto tensioner
pulleyFig. 1.28 TDC marks (1) at front of engine
(Sec 28)
Fig. 1.30 Cylinder head bolt tightening
sequence (Sec 29)28.10 Tightening timing belt cover nut29.13 Using a crowfoot type wrench on a
cylinder head bolt
1

2The big-end bearing shells can be renewed
without having to remove the cylinder head if
the caps are unbolted and the
piston/connecting rod pushed gently about
one inch up the bore (the crankpin being at its
lowest point). If these shells are worn,
however, the main bearing shells will almost
certainly be worn as well. In this case, the
engine should be removed for complete
overhaul including crankshaft removal.
3To remove the piston/connecting rods,
remove the cylinder head as described in
Section 29.
4Grip the oil pick-up pipe and twist or rock it
from its hole in the crankcase. It is an
interference fit in the hole.
5Unscrew the nuts from the big-end caps,
then remove the caps with their bearing
shells. The caps and their connecting rods are
numbered 1, 2, 3 and 4 from the timing cover
end of the engine. The numbers are adjacent
at the big-end cap joint and on the side of the
crankcase furthest from the auxiliary shaft.
6If the bearing shells are to be used again,
tape them to their respective big-end caps.
7Push each connecting rod/piston assembly
up the bore and out of the cylinder block.
There is one reservation; if a wear ridge has
developed at the top of the bores, remove this
by careful scraping before trying to remove
the piston/rod assemblies. The ridge will
otherwise prevent removal or break the piston
rings during the attempt.
8If the connecting rod bearing shells are to
be used again, tape the shells to their
respective rods.
9Dismantling the piston/connecting rod is
described in Section 18.
Refitting
10Fit the new shells into the connecting rod
and caps, ensuring the surfaces on which the
shells seat, are clean and dry.
11Check that the piston ring gaps are evenly
spaced at 120º intervals. Liberally oil the rings
and the cylinder bores.
12Fit a piston ring clamp to compress the
rings.
13Insert the piston/connecting rod into the
cylinder bore, checking that the rod assembly
is correct for that particular bore. The cap and
rod matching numbers must be furthest away
from the auxiliary shaft (Fig. 1.31).14Push the piston into the bore until the
piston ring clamp is against the cylinder block
and then tap the crown of the piston lightly to
push it out of the ring clamp and into the bore
(photo).
15Oil the crankshaft journal and fit the
big-end of the connecting rod to the journal.
Fit the big-end cap and nuts, checking that
the cap is the right way round (photo).
16Tighten the big-end nuts to the specified
torque. The correct torque is important as the
nuts have no locking arrangement. After
tightening each big-end, check the crankshaft
rotates smoothly (photo).
17Refit the oil pick-up pipe, the cylinder
head, oil pump and sump pan, all as
described earlier.
18Refill the engine with oil and coolant.
33 Engine mountings-
renewal
1
1Three engine/transmission flexible
mountings are used.
2To renew a mounting, support the weight of
the engine/transmission on a hoist or jack and
unbolt and remove the mounting.
3In the unlikely event of all three mountings
requiring renewal at the same time, only
disconnect them and renew them one at a
time.
34 Engine- method of removal
1The engine complete with transmission
should be removed by lowering it to the floor
and withdrawing it from under the front of the
car which will have been raised to provide
adequate clearance.
35 Engine/transmission-
removal and separation
3
1Open the bonnet, disconnect the
windscreen washer tube.
2Mark the hinge positions on the undersideof the bonnet and then with the help of an
assistant to support its weight unbolt and
remove the bonnet to a safe place.
3Disconnect the battery negative lead.
4Drain the cooling system and the engine
and transmission oils.
5Remove the air cleaner.
6From the rear of the alternator disconnect
the electrical leads.
7Disconnect the leads from the starter
motor, oil pressure and coolant temperature
switches, also the oil temperature switch.
8Disconnect the LT lead from the distributor
and the HT lead from the ignition coil.
9Disconnect the clutch cable from the
release lever at the transmission. Also
disconnect the speedometer drive cable
(knurled ring).
10Pull the leads from the reversing lamp
switch.
11Disconnect all coolant hoses from the
engine. Also disconnect the brake servo hose
from the intake manifold.
12Disconnect the choke and throttle
controls from the carburettor.
13Disconnect the inlet hose from the fuel
pump and plug the hose.
14Disconnect the fuel return hose from the
carburettor.
15Disconnect the coolant hoses from the
carburettor throttle block.
16Raise the front of the car and remove the
front roadwheels.
17Unscrew and remove the driveshaft to
hub nuts. These are very tight and a long
knuckle bar will be required when unscrewing
them. Have an assistant apply the brake pedal
hard to prevent the hub from turning.
18Working under the car, remove the inner
wing protective shields and then disconnect
the exhaust downpipe from the manifold.
19Disconnect the exhaust pipe sections by
removing the socket clamp just forward of the
rear axle beam. Remove the front section.
20Disconnect the forward ends of the
gearchange rods by prising their sockets from
the ballstuds.
21Unscrew the nuts on the steering tie-rod
end balljoints and then using a suitable
“splitter” tool, separate the balljoints from the
steering arms.
22Unbolt the front brake hose support clips
1116 cc and 1301 cc engine 1•27
32.16 Tightening a big-end cap nut32.15 Fitting a big-end cap32.14 Fitting piston into cylinder bore
1

from the suspension struts and then remove
the bolts which secure the hub carriers to the
U-clamps at the base of the suspension
struts.
23Pull the tops of the hub carriers down and
then outwards and push the driveshafts from
them.
24Unbolt the driveshaft inboard boot
retainers and then remove the driveshafts
from the transmission.
25Support the engine on a hoist or use a
trolley jack under the engine/transmission.
Remove the bottom mounting and then the
upper left and right-hand ones.
26Lower the power unit to the floor by
pushing it to the left-hand side to clear the
right-hand mounting bracket and then swivel
the gearbox towards the rear of the car.
Withdraw the engine/transmission from under
the car.
27External dirt and grease should now be
removed using paraffin and a stiff brush or a
water-soluble solvent.
28Unbolt and remove the engine mounting
brackets and the starter motor.
29Unbolt and remove the cover plate with
the gearchange ball stud strut from the lower
front face of the flywheel housing.
30With the engine resting squarely on its
sump pan, unscrew the flywheel housing
connecting bolts, noting the location of any
lifting lugs and hose and wiring clips.
31Support the weight of the transmission
and withdraw it in a straight line from the
engine.
36 Engine- dismantling (general)
Refer to Section 14, Part 2.
37 Engine ancillary components
- removal
Refer to Section 15, Part 2 and also remove
the intake manifold.
38 Engine-
complete dismantling
3
1Have the engine resting squarely and
supported securely on the work surface.
2Unbolt and remove the timing belt cover.
3Grip the now exposed timing belt with the
hands and loosen the camshaft sprocket.
4Release the timing belt tensioner pulley
centre bolt, then slip the belt from the pulley
and sprockets to remove it. Note which way
round the belt is fitted, usually so that the
lettering on the belt can be read from the
crankshaft pulley end of the engine.
5Remove the camshaft sprocket.6Unbolt and remove the camshaft timing belt
cover backing plate.
7Unbolt and remove the camshaft carrier
cover.
8Unbolt the camshaft carrier and lift it off
very slowly, at the same time pushing the cam
followers and their shims down with the
fingers securely onto their respective valve
springs. It is easy to remove the camshaft
carrier too quickly with some of the cam
followers stuck in it and as the carrier is lifted
away, the cam followers will fall out. If this
happens, the valve clearances will be upset as
the cam followers and shims cannot be
returned, with any certainty, to their original
positions. Keep the cam followers and shims
in their originally fitted order.
9Unscrew and remove the cylinder head
bolts and nuts, grip the manifold, rock the
head and remove the complete cylinder
head/manifold/carburettor assembly. Remove
and discard the cylinder head gasket.
10Unbolt the coolant pump from the side of
the cylinder block and remove it complete
with coolant distribution pipe. Remove the
crankcase breather.
11Remove the distributor/oil pump
driveshaft. This is simply carried out by
inserting a finger into the hole vacated by the
distributor and wedging it in the hole in the
end of the driveshaft. Lift the shaft out of
mesh with the auxiliary shaft. Where the
distributor is driven by the camshaft, a cover
plate retains the oil pump driveshaft in
position.
12Unbolt and remove the sprocket from the
end of the auxiliary shaft. The sprocket is held
to the shaft with a Woodruff key.
13Unbolt the auxiliary shaft retainer and
withdraw the shaft from the crankcase.
14Unscrew and remove the crankshaft
pulley nut. This is very tight and the flywheel
starter ring gear will have to be jammed with a
cold chisel or a suitably bent piece of steel to
prevent the crankshaft rotating.
15Withdraw the crankshaft sprocket, which
is located by the Woodruff key.
16Unbolt the front engine mounting bracket
from the cylinder block, together with the
timing belt cover screw anchor bush. Unbolt
and remove the timing belt tensioner pulley.
17Unscrew the flywheel securing bolts. Thestarter ring gear will again have to be jammed
to prevent the crankshaft rotating as the bolts
are unscrewed. Mark the flywheel position in
relation to the crankshaft mounting flange,
then remove it.
18Unbolt the front and rear crankshaft oil
seal retainer bolts from the crankcase and the
sump. Remove the oil seal retainers.
19Turn the engine on its side, extract the
remaining sump bolts and remove the sump.
If it is stuck, try tapping it gently with a
soft-faced hammer. If this fails, cut all round
the sump-to-gasket flange with a sharp knife.
Do not try prising with a large screwdriver; this
will only distort the sump mating flange.
20With the sump removed, unbolt and
remove the oil pump.
21Grip the oil pick-up pipe and twist or rock
it from its hole in the crankcase. It is an
interference fit in the hole.
22Remove the piston/connecting rods as
described in Section 32.
23Before unbolting the main bearing caps,
note that they are marked with one, two, three
or four notches. No. 5 main bearing cap is
unmarked. Note that the notches are nearer
the auxiliary shaft side.
24Unbolt and remove the main bearing
caps. If the bearing shells are to be used
again, tape them to their respective caps. The
bearing shell at the centre position is plain,
the others have a lubricating groove.
25Carefully, lift the crankshaft from the
crankcase, noting the thrust washers at No. 5
main bearing. These control the crankshaft
endfloat.
39 Cylinder head- dismantling
and decarbonising
4
1The operations are similar to those
described for the ohv engine in Section 17 in
respect of decarbonising and valve grinding.
2To remove a valve, use a valve spring
compressor to compress the first valve and
then extract the split collets (photo).
3Release the valve spring compressor.
4Withdraw the valve spring cap and the
double valve springs (photos).
5Remove the valve (photo).
1•28 1116 cc and 1301 cc engine
39.4A Valve spring cap39.2 Valve spring compressor and split
collets

prevent the flywheel turning. Fit the engine
endplate (photo).
20Fit the timing belt sprocket to the front
end of the crankshaft (photo).
21Fit the crankshaft pulley and the nut;
tighten it to the specified torque, again
jamming the starter ring gear to prevent the
crankshaft from rotating (photo).
Cylinder head
22Refitting is described in Section 29.
Camshaft carrier and camshaft
23Refitting is described in Section 27.
Timing belt and tensioner
24Refitting is described in Section 28, but
make sure that the belt cover rear plate is
bolted into position. If the engine mounting
bracket was removed, bolt it into positioncomplete with the tensioner plunger to
provide spring pressure to the belt pulley
(photos).
Valve clearances
25Check the valve clearances as described
in Section 26.
26Using new gaskets, bolt on the camshaft
carrier cover plate and the inlet and exhaust
manifolds using new gaskets. Fit the exhaust
manifold hot air collector plate (photo).
27Locate the engine rear plate on its dowels
by sliding it behind the flywheel (photo).
43 Engine ancillaries- refitting
1Bolt on the carburettor (Chapter 3). 2Fit the coolant pump and thermostat
housing (Chapter 2).
3Fit the alternator and tension the drivebelt
(Chapters 9 and 2).
4Fit the distributor (Chapter 4).
5Fit the fuel pump (Chapter 3).
6Fit the clutch (Chapter 5).
7Fit a new oil filter cartridge (Section 2 of this
Chapter).
44 Engine/transmission-
reconnection and refitting
3
1Offer the transmission to the engine making
sure that the clutch has been centralised as
described in Chapter 5 (photo).
1•32 1116 cc and 1301 cc engine
44.1 Offering transmission to engine42.27 Engine rear plate42.26 Tightening a camshaft carrier cover
nut
42.24C Engine mounting bracket with belt
tensioner plunger (arrowed)
42.24B Belt cover mounting stud42.24A Belt cover rear plate
42.21 Crankshaft pulley and nut42.20 Fitting crankshaft timing belt
sprocket42.19 Tightening flywheel bolts

2Draw the engine and transmission together
by screwing in the connecting bolts.
Refit lifting lugs and hose and wiring clips
(photo).
3Bolt the lower cover plate to the face of the
flywheel housing.
4Bolt the starter motor into position.
5Bolt the mounting brackets into place.
6Place the engine/transmission on the floor
ready for raising by hoist or jack into the
engine compartment.
7Raise the car and position it over the
engine/transmission.
8Hoist or jack the power unit upwards until
the left and right-hand mountings can be
connected (photos).9Remove the lifting mechanism and connect
the bottom mounting (photos).
10Connect the inboard ends of the
driveshafts with the transmission and the
outboard ends with the hub carriers.
11Reconnect the hub carriers with the
clamps at the base of the suspension struts.
Tighten the fixing bolts to the specified torque.
12Bolt the brake flexible hose support clips
to the suspension struts.
13Reconnect the tie-rod end balljoints
tightening the nuts to the specified torque.
14Reconnect the gearchange rods. The
easiest way to do this is to force the sockets
onto the ball studs using a pair of self-locking
grips (photo).15Refit the exhaust system and
reconnect the downpipe to the manifold
(photo).
16Screw on the driveshaft nuts and tighten
them to the specified torque. Have an
assistant apply the brake pedal hard to
prevent the driveshaft from turning.
17Refit the front roadwheels and lower the
car to the floor.
18Reconnect the carburettor fuel and
coolant hoses.
19Unplug the fuel hose and connect it to the
pump.
20Reconnect the choke and throttle controls
to the carburettor.
21Reconnect the coolant and heater hoses
1116 cc and 1301 cc engine 1•33
44.8B Left-hand engine mounting44.8A Raising engine/transmission into
engine compartment44.2 Lifting lug at bellhousing bolt
44.15 Exhaust downpipe flange nuts44.14 Connecting a gearchange rod ball
cup44.9B Lower mounting attachment bolts
44.9A Engine/transmission lower mounting44.8D Right-hand mounting bolted up44.8C Right-hand engine mounting
brackets
1

to the engine. Also reconnect the brake servo
hose to the intake manifold (photos).
22Reconnect the leads to the reversing lamp
switch. Reconnect the transmission earth lead
(photos).
23Reconnect the clutch cable and adjust as
described in Chapter 5.
24Reconnect the speedometer drive cable
to the transmission and tighten the knurled
retaining ring.
25Reconnect the low tension lead to the
distributor and the high tension lead to the
ignition coil.
26Reconnnect the electrical leads to thestarter motor, the oil pressure and
temperature switches and the coolant
temperature switch.
27Connect the leads to the alternator.
28Refit the air cleaner.
29Refill the cooling system. Refill the engine
with oil.
30Reconnect the battery.
31Refit the bonnet and connect the
windscreen washer tube.
32Fit the inner wing protective shields
(photo).
45 Engine- initial start-up after
major overhaul
4
1If new bearings and rings have been fitted,
it is likely that the engine will be stiff to turn so
make sure the battery is well charged.
2Switch on the ignition and check that
appropriate warning lights come on.
3Start up the engine. If it refuses to start,
refer to the “Fault Finding” Section in the
Reference section of this Manual.
4Watch the oil pressure warning light and
alternator charging indicator light. If there is
no charge or if the oil pressure warning light
does not go out after a second or two, havinghad time to fill the new oil filter, switch off and
recheck.
5If the warning lights go out, set the engine
to run on fast idle and check the engine for
leaks.
6Check the coolant level; it will probably go
down as air locks are filled.
7Keep the engine running at a fast idle and
bring it up to normal working temperature. As
the engine warms up, there will be some odd
smells and smoke from parts getting hot and
burning off oil deposits.
8When the engine running temperature has
been reached, adjust the idling speed, as
described in Chapter 3. Check and, if
necessary, adjust the ignition timing using a
stroboscope (see Chapter 4).
9Stop the engine and wait a few minutes;
check to see if there are any coolant or oil
leaks.
10Road test the car to check that the engine
is running with the correct smoothness and
power. If it does not, refer to “Fault finding” in
the Reference section of this Manual. Do not
race the engine. If new bearings and/or
pistons and rings have been fitted, it should
be treated as a new engine and run it at
reduced speed for at east 800 km (500 miles).
11After 800 km (500 miles) change the
engine oil and filter.
1•34 1116 cc and 1301 cc engine
44.32 Inner wing protective shield44.26B Coolant temperature switch44.26A Oil pressure warning switch
44.22B Transmission earth lead
44.22A Reversing lamp switch on
transmission44.21B Brake servo hose at manifold44.21A Heater hose at manifold

Engine idles roughly
m mMixture too weak
m mAir leak in carburettor
m mAir leak at inlet manifold to cylinder head, or inlet manifold to
carburettor
m mCarburettor incorrectly adjusted
m mOther fuel system fault (see Chapter 3)
m mLow tension leads on coil loose
m mLow tension lead to distributor loose
m mDirty, incorrectly set, or pitted contact breaker points
m mTracking across inside of distributor cover
m mFaulty coil
m mIgnition leads loose
m mSpark plugs fouled or incorrectly gapped.
m mIgnition timing incorrect
m mOther ignition fault (see Chapter 4)
m mIncorrect valve clearances
m mWidely differing cylinder compressions
m mLow battery voltage (charging fault)
m mBattery leads loose on terminals
m mBattery earth strap loose on body attachment point
m mEngine earth lead loose
Pre-ignition (pinking) during acceleration
m
mIncorrect grade of fuel being used
m mIgnition timing over-advanced
m mOther ignition fault (see Chapter 4)
m mEngine overheated
m mExcessive carbon build-up
m mFuel system fault (see Chapter 3)
m mValve timing incorrect (after rebuild)
m mMixture too weak
Engine runs on after switching off
m
mIdle speed too high
m mIncorrect type of spark plug
m mOverheating
m mExcessive carbon build-up
m mOther emission control fault (see Chapter 3)
Oil being lost due to leaks
m
mLeaking oil filter gasket
m mLeaking rocker cover gasket
m mLeaking timing gear cover gasket
m mLeaking sump gasket
m mLoose sump plug
Low oil pressure (verify accuracy of sender before
dismantling engine!)
m mOil level low
m mEngine overheating
m mIncorrect grade of oil in use
m mOil filter clogged or bypass valve stuck
m mPressure relief valve stuck or defective
m mOil pick-up strainer clogged or loose
m mMain or big-end bearings worn
m mOil pump worn or mountings loose
Excessive oil consumption
m
mOverfilling
m mLeaking gaskets or drain plug washer
m mValve stem oil seals worn, damaged or missing after rebuild
m mValve stems and/or guides worn
m mPiston rings and/or bores worn
m mPiston oil return holes clogged
Oil contaminated with water
m
mExcessive cold running
m mLeaking head gasket
m mCracked block or head
Oil contaminated with fuel
m
mExcessive use of choke
m mWorn piston rings and/or bores
Unusual mechanical noises
m
mUnintentional mechanical contact (eg fan blade)
m mWorn drivebelt
m mWorn valvegear (tapping noises from top of engine) or incorrect
clearance
m mPeripheral component fault (generator, coolant pump)
m mWorn big-end bearings (regular heavy knocking, perhaps less under
load)
m mWorn main bearings (rumbling and knocking, perhaps worsening
under load)
m mSmall-end bushes or gudgeon pins worn (light metallic tapping)
m mPiston slap (most noticeable when engine cold)
m mWorn timing chain and gears (rattling from front of engine)
m mWorn crankshaft (knocking, rumbling and vibration)
1•36 All engines

2
System type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . “No loss” with radiator and integral expansion tank. Electric cooling
fan, belt-driven coolant pump, thermostat on cylinder head
General
Radiator fan cuts in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 to 94ºC (194 to 201ºF)
Radiator fan switches off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 to 89ºC (185 to 192ºF)
Thermostat opens:
903 cc engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 to 89ºC (185 to 192ºF)
1116 cc and 1301 cc engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 to 87ºC (181 to 188.6ºF)
Fully open:
903 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100ºC (212ºF)
1116 cc and 1301 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95ºC (203ºF)
Expansion tank pressure cap rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.78 bar (11 lbf/in2)
Coolant
Capacity:
903 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.6 litre (8.1 pint)
1116 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.0 litre (10.6 pint)
1301 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2 litre (10.9 pint)
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ethylene glycol based antifreeze
Torque wrench settingsNm lbf ft
Temperature sender switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Coolant pump mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 25
Alternator adjuster and mountings nuts . . . . . . . . . . . . . . . . . . . . . . . . . 49 36
Chapter 2 Cooling and heating systems
For modifications, and information applicable to later models, see Supplement at end of manual
Coolant mixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Coolant pump - removal, overhaul and refitting . . . . . . . . . . . . . . . . 9
Cooling system - draining, flushing and refilling . . . . . . . . . . . . . . . . 2
Cooling system sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Description and maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Drivebelt - tensioning and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Fault finding - cooling and heating . . . . . . . . . . . . See end of ChapterHeater - dismantling, overhaul and reassembly . . . . . . . . . . . . . . . . 13
Heater unit - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Heating and ventilation system - description . . . . . . . . . . . . . . . . . . 11
Radiator - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Radiator fan thermostatic switch - removal, checking and refitting . 5
Radiator fan - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . 6
Thermostat - removal, testing and refitting . . . . . . . . . . . . . . . . . . . . 4
2•1
Specifications Contents
1 Description and
maintenance
1
1The cooling system consists of a
front-mounted radiator with built-in expansion
tank, a coolant pump (belt-driven from the
crankshaft pulley) and a thermostatically-
controlled electric cooling fan.
2In order to assist rapid warm-up, athermostat is located in a housing at the
left-hand end of the cylinder head. The hose
connections to the thermostat housing vary
according to model.
3The heater is supplied with coolant from the
engine and incorporates a matrix and blower
with the necessary controls.
4The throttle valve plate block of the
carburettor is coolant-heated as a means of
improving fuel atomisation.
5Maintenance is minimal as in theory no
coolant should ever be lost from theexpansion tank. Regularly check that the
coolant level is between 50.0 and 70.0 mm
(1.97 and 2.8 in) above the MIN mark on the
tank with the engine cold. The need for
regular topping up will indicate a leak
somewhere in the system. If one cannot be
found suspect an internal leak in the engine
although this is usually confirmed by a rise in
the engine oil level and water on the dipstick
(photo). Any topping-up should be done using
an antifreeze mixture (see Section 3), not plain
water.
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

6Avoid unscrewing the expansion tank cap
when the engine is hot, but if this must be
done, cover the cap with a cloth to avoid
scalding by escaping steam.
7Periodically, check the condition of all
coolant hoses and tighten the clips.
2 Cooling system- draining,
flushing and refilling
1
1Set the heater temperature lever to
maximum.
2Unscrew the cap from the expansion tank.
3Disconnect the radiator bottom hose and
unscrew the cylinder block drain plug (1116
cc and 1301 cc engines) and allow the coolant
to drain. Refer to photo 29.21B, page 64.
4If the system is in good condition with no
sign of rust or dirt in the drained coolant, then
it may be refilled immediately. If the system
has been neglected and the antifreeze has notbeen regularly renewed and there is evidence
of rust and sediment in the drained liquid then
flush the system through with a cold water
hose.
5If the radiator should appear to be clogged,
it may be necessary to remove it (Section 7)
invert it and reverse flush it using a cold water
hose. If, after a reasonable period the water
still does not run clear, the radiator should be
flushed with a good proprietary cleaning
system. Extensive damage should be repaired
by a specialist or the unit exchanged for a
new or reconditioned radiator.
6Reconnect the bottom hose and screw in
the drain plug.
7Remove the plug (B) (Fig. 2.2) from the
bleed hole in the heater hose.
8Remove the plug (D) (Fig. 2.3) from the
bleed hole in the expansion tank.
9Pour antifreeze mixture slowly into the filler
neck of the expansion tank until it is seen to
come out of the expansion tank plug hole.
Screw in the plug.
10Add further coolant until it is seen todribble out of the hole in the heater hose.
Screw in the plug.
11Top up the expansion tank to the
specified level and screw on the tank cap.
12Start the engine and run it until the cooling
fan cuts in. Switch off, allow to cool and top
up if necessary to the specified mark on the
expansion tank.
3 Coolant mixtures
1In cold climates, antifreeze is needed for
two reasons. In extreme cases, if the coolant
in the engine freezes solid it could crack the
cylinder block or head. But also in cold
weather, with the circulation restricted by the
thermostat, and any warm water that is
getting to the radiator being at the top, the
bottom of the radiator could freeze, and so
block circulation completely, making the
coolant trapped in the engine boil.
2The antifreeze should be mixed in the
proportions advocated by the makers,
according to the climate. There are two levels
of protection. The first cuts risk of damage, as
the antifreeze goes mushy before freezing.
The second, valid all year round, is the
corrosion protection it offers - see below. The
normal proportion in a temperate climate to
provide maximum protection against freezing
and corrosion is 50% antifreeze and
50% water.
3Use only ethylene glycol based antifreeze
and preferably soft water.
4Antifreeze should be left in through the
summer. It has an important secondary
function, to act as an inhibitor against
corrosion. In the cooling system are many
different metals, in particular the aluminium of
the cylinder head. In contact with the coolant
this sets up electrolytic corrosion,
accentuated by any dirt in the system. This
corrosion can be catastrophically fast.
5After about two years, the effectiveness of
the antifreeze’s inhibitor is used up. It must
then be discarded, and the system refilled
with new coolant.
6In warm climates free from frost, an
2•2 Cooling and heating systems
Fig. 2.3 Plug (D) in expansion tank (Sec 2)Fig. 2.2 Plug (B) in heater hose (Sec 2)
1.5 Expansion tank cap
Fig. 2.1 Cooling system on 903 cc engine (Sec 1)

inhibitor should be used. Again, a reputable
make giving full protection must be chosen
and renewed every two years. Inhibitors with
dyes are useful for finding leaks, and on some
makes the dye shows when the inhibiting
ability is finished.
4 Thermostat-
removal, testing and refitting
1
1The thermostat assembly is mounted on the
flywheel end of the cylinder block.
2Unfortunately, the thermostat/housing is a
complete unit and failure of the thermostat will
necessitate the purchase of the complete
component (photo).
3If the thermostat/housing is removed from
the engine, it can be suspended in water and
the water heated to check out its opening
temperature. Movement of the thermostat
valve can be observed to some extent
through the openings in the housing.
4When refitting, always use a new gasket at
its mounting face (photo).
5 Radiator fan thermostatic
switch- removal, checking
and refitting
1
1Drain the cooling system.
2If the thermostatic switch is being removed
because the fan is not operating and the
switch is suspect, check the fan fuse first,
before removing the switch.3To remove the switch, disconnect the leads
from the terminals and unscrew the switch.
4Connect a test bulb and battery across the
switch terminals and then immerse the
sensing part of the switch in a container of
water. Heat the water and, using a
thermometer, check the temperature of the
water when the bulb lights up, indicating the
switch is functioning. The switch should
operate at approximately 194ºF (90ºC). Allow
the water to cool and check that the switch
cuts out at 185ºF (85ºC). Renew a faulty
switch.
5Refitting of the switch is the reverse of the
removal procedure. Always fit a new O-ring on
the switch.
6 Radiator fan-
removal and refitting
1
1Disconnect the electrical leads from the
radiator fan motor.
2Unbolt the fan mounting struts from the
radiator and lift the complete assembly away.
3Refitting is a reversal of removal.
7 Radiator-
removal and refitting
1
1Drain the cooling system.
2Disconnect the electrical leads from the
radiator fan motor and thermostatic switch.3Disconnect the coolant hoses from the
radiator (photos).
4Release the clips from the top of the
radiator and withdraw the radiator complete
with fan from the engine compartment
(photos).
5The radiator is of combined plastic/metal
construction and any repair should be left to
specialists. In an emergency however, minor
leaks from the radiator may be cured by using
a radiator sealant with the radiator in situ.
6Refitting is a reversal of removal. Fill the
cooling system as described in Section 2.
8 Drivebelt-
tensioning and renewal
1
1The drivebelt for the alternator and coolant
pump is correctly tensioned if it deflects
through 10.0 mm (0.39 in) under moderate
thumb pressure at the mid point of the longest
run of the belt.
2To tighten the belt, release the mounting
and adjuster nuts on the alternator and prise
the alternator away from the engine. Tighten
the nuts when the belt is taut and then
re-check the tension as previously described.
Never over-tension a belt or the coolant pump
or alternator bearings may be damaged.
3Check the condition of the belt at regular
intervals. If frayed or cracked, renew it in the
following way.
4Release the alternator mounting and
adjuster nuts and push the alternator fully in
Cooling and heating systems 2•3
7.3A Radiator top hose4.4 Fitting thermostat housing
(1116 cc engine)4.2 Thermostat housing
7.4B Removing radiator/fan assembly7.4A Radiator fixing clip7.3B Radiator hose to thermostat housing
2