1983 FIAT UNO engine oil

crankcase. If the shells are to be used again,
keep them with their respective bearing caps.
70The thrust washers which control
crankshaft endfloat are located in the
crankcase, and retained by the turned-over
edges of the centre main bearing shell.
71The engine is now fully stripped.
Examination and renovation
72The procedures for the following items are
essentially as described in Chapter 1, Sec-
tion 18.
Cylinder block and crankcase
Crankshaft and bearings
Flywheel
Oil seals and gaskets
Cylinder head
73Using a straight-edge, check the cylinder
head gasket surface for distortion. If it
exceeds the specified tolerance, it must be
surface ground by your dealer.74Refer to Chapter 1, Section 39, for
dismantling and renovation operations. Note
that single valve springs are fitted.
Oil pump
75Checking operations are described in
sub-Section B.
Pistons and connecting rods
76Refer to sub-Section B.
77If one or more connecting rods are
changed, it is important that its weight is
identical to that of the original. Use an
accurate balance to weigh them and remove
metal if necessary from the new rod in the
areas indicated in Fig. 13.7.
Camshaft and cam followers
78If the camshaft journals or bearings show
any sign of wear or scoring, then the
camshaft, or cylinder head, or both must be
renewed.
79The cam followers should be checked for
ovality using a micrometer. Unless unworn
they should be renewed.
Timing belt tensioner and timing belt
80The tensioner is a lubricant-sealed pulley,
and it should be tested for smooth and quiet
operation by turning it with the fingers. Any
evidence of roughness or rattle will indicate
the need for a new assembly (photo).81The timing belt should be inspected at
regular intervals for correct adjustment and
condition (see Section 3 or “Routine
maintenance” at the beginning of the Manual).
If there is evidence of worn teeth, cracking or
fraying, or oil contamination, renew the belt.
The vehicle manufacturers recommend that
the belt is renewed whenever it is removed,
and it should certainly be renewed at the
intervals specified in Section 3 or the main
“Routine maintenance” section at the
beginning of this Manual as a precautionary
measure against belt breakage and
consequent expensive engine damage.
PART D:
ENGINE REASSEMBLY AND
REFITTING
Reassembly - general
1Refer to Chapter 1, Section 19.
Complete reassembly#
2With the cylinder block/crankcase standing
on the work surface, fit the bearing half shells
into their crankcase seats (photo). Make sure
that the seats are perfectly clean as dirt or grit
trapped under the shell will cause binding
when the crankshaft is turned.
3The centre bearing crankcase web
incorporates the thrust washers held by the
lips of the bearing shell (photo).
4Oil the shells and lower the crankshaft into
the crankcase (photo).
5Fit the bearing shells into the main bearing
caps, again making sure that the shell seats
are perfectly clean (photo).
13•30 Supplement: Revisions and information on later models
5D.5 Main bearing cap and shell5D.4 Fitting the crankshaft5D.3 Crankshaft thrust washer at centre
bearing
5D.2 Main bearing shell in crankcase
Fig. 13.8 Checking a cam follower for
ovality - 999 and 1108 cc engine (Sec 5C)
Fig. 13.7 Metal removing areas (arrowed)
on connecting rod - 999 and 1108 cc
engine (Sec 5C)
5C.80 Timing belt tensioner

6Fit the main bearing caps in their numbered
sequence and the correct way round (photo).
7Clean the threads of the main bearing cap
bolts, lightly oil them and screw them in
finger-tight. Tighten all bolts progressively to
the specified torque, then check that the
crankshaft turns smoothly and evenly
(photos).
8Now check the crankshaft endfloat. Do this
using a dial gauge or feeler blades inserted
between the machined shoulder of a journal
and the side of the bearing cap (photo). Move
the crankshaft fully in one direction and then
the other to ensure that full movement is
obtained. If the endfloat is outside the
specified tolerance and new bearing shellshave been fitted, then a fault must have
occurred during crankshaft regrinding.
9Fit a new oil seal to the crankshaft rear oil
seal retainer. Apply grease to the seal lips. A
conventional gasket is not used at the oil seal
joint face but a 3.0 mm diameter bead of RTV
silicone instant gasket must be applied
to a clean surface as shown in Fig. 13.9
(photo).
10Bolt the retainer into position. One hour at
least must be allowed for the RTV to cure
before oil contacts it.
11Turn the engine on its side and fit the
piston/connecting rods as described in
sub-Section B.
12Fit a new oil seal to the oil pump, oil theseal lips and bolt on the pump using a new
joint gasket (photos).
13Use a new sealing washer and fit the oil
pick-up/filter screen assembly.
14Fit the engine rear plate and then the
flywheel on its mounting flange. Apply
thread-locking fluid to (clean) bolt threads and
screw in the bolts to the specified torque
(photo). Hold the flywheel against rotation by
locking the starter ring gear with a suitable
tool.
15Fit the sump pan as described in
sub-Section B.
16Fit the crankshaft sprocket so that the
timing mark is visible. Lock the flywheel
starter ring gear teeth, and screw in and
Supplement: Revisions and information on later models 13•31
5D.7B Angle-tightening a main bearing cap
bolt5D.7A Initial tightening of a main bearing
cap bolt5D.6 Fitting a main bearing cap
5D.14 Tightening a flywheel bolt5D.12B Tightening an oil pump bolt5D.12A Oil pump gasket
5D.9 Fitting crankshaft rear oil seal
retainerFig. 13.9 Application area for silicone
gasket on crankshaft rear oil seal retainer
(Sec 5D)5D.8 Checking crankshaft endfloat using a
dial gauge
13

tighten the sprocket bolt to the specified
torque (photos).
17Refit the clutch to the flywheel asdescribed in Chapter 5. Make sure that the
driven plate is centralised.
18Fit the cylinder head.
19Refit the coolant pump. A conventional
gasket is not used at the joint face, but apply
a continuous bead of RTV silicone instant
gasket 3.0 mm in diameter to the pump
mating surface. Allow at least one hour for
curing before permitting coolant to contact it.
20Fit the timing belt rear cover, then the
timing belt tensioner and lock in its retracted
position (photo).
21Fit and tension the timing belt as
described in sub-Section B.
22Bolt on the crankshaft pulley (photo).
23Refit the alternator and drivebelt (photo).
24Refit the engine oil dipstick.
25Using a new gasket, bolt on the inletmanifold, tightening the nuts to the specified
torque (photos).
26Refit the carburettor, or throttle body, as
appropriate.
27Fit the fuel pump, insulator block and
actuating rod, if applicable. Make sure that a
new gasket is placed on each side of the
pump insulator block.
28Using a new gasket, bolt on the
thermostat housing.
29Oil the sealing ring of a new oil filter
cartridge and screw it into position using hand
pressure only (photo).
30Refit the coolant distribution pipe to the
rear of the coolant pump. Use a new seal
(photo).
31Using a new gasket, bolt on the exhaust
manifold (photo).
13•32 Supplement: Revisions and information on later models
5D.31 Exhaust manifold5D.30 Coolant distribution pipe5D.29 Oil filter cartridge and mounting
base
5D.25B Fitting the inlet manifold5D.25A Inlet manifold gasket5D.23 Alternator and drivebelt
5D.22 Crankshaft pulley installation
5D.20 Fitting the timing belt rear cover5D.16B Tightening the crankshaft sprocket
bolt5D.16A Crankshaft sprocket showing
integral key

32Fit the hot air collector plate for the air
cleaner (photo).
33Refer to Section 10 and fit the distributor.
34Bolt on the timing belt cover.
35Fit the camshaft cover, using a new
gasket unless the original one is in perfect
condition.
Engine/transmission -
reconnection and refitting#
36Locate the engine in an upright position
on wooden blocks to allow for the greater
depth of the transmission flywheel housing
when it is joined to the engine.
37Make sure that the clutch driven plate has
been centralised, offer the transmission to the
engine and locate the flywheel housing on the
single stud and dowels.
38Tighten the connecting bolts to specifiedtorque, having located the lifting eye (photo).
39Bolt on the starter motor.
40Refit the cover plate to the flywheel
housing, but do not insert the lower bolts at
this stage as they retain the support bracket
for the gearchange rod.
41The engine and transmission are now
ready for refitting. The operations are a direct
reversal of the operations described earlier,
but observe the following points.
42Have the engine/transmission perfectly
horizontal and suspended on the hoist.
43Lower it into position very slowly until it is
possible to engage the driveshaft inboard
joints with the transmission.
44Continue lowering until the driveshafts
can be fully engaged and the mountings
reconnected. Remove the hoist.
45Tighten all nuts and bolts to the specifiedtorque. Note the method shown for
connecting the gearchange rod ball socket
using pliers (photo).
46Refill the engine with oil and coolant and
replenish the transmission oil.
Initial start-up after major
overhaul
47Refer to Chapter 1, Section 45.
6 Engine-
1301 cc Turbo ie
PART A: GENERAL
Description
1This engine is similar in design to the
1301 cc engine described in Chapter 1, but
the fuel and ignition systems are different, and
a turbocharger, oil cooler and intercooler are
fitted.
2Many dimensions and tolerances have
been altered for this engine, and reference
should be made to the Specifications at the
beginning of this Supplement.
3Operations which differ from those
described in Chapter 1 are given in the
following sub-Sections.
Lubrication system - description
4The lubrication system differs from the
non-Turbo 1301 cc engine in the following
respects.
5An oil cooler is fitted, which comprises a
matrix with inlet and outlet hoses connected
to the oil filter cartridge mounting base.
6A thermostatic control switch is fitted,
which diverts the oil flow through the matrix
only at oil temperatures above 84ºC (183ºF).
Note that a faulty switch will require renewal
of the complete oil filter mounting base.
7Special oil spray nozzles are located in the
crankcase main bearing webs, to cool the
underside of the pistons.
8The ball-type valves in the nozzles open
when the engine oil pressure reaches 1.2 bars
(17.4 lbf/in
2).
9An oil pressure sender unit is screwed into
Supplement: Revisions and information on later models 13•33
5D.45 Connecting ball socket type
gearchange rod5D.38 Lifting eye on flywheel housing
flange5D.32 Air cleaner hot air collector plate
Fig. 13.10 Cutaway view of the 1301 cc Turbo ie engine (Sec 6A)
13

the crankcase to operate the oil pressure
gauge. In addition, a low oil pressure switch
screwed into the camshaft oil gallery actuates
a warning light on the instrument panel in theevent of the pressure dropping dangerously
low (photo).
10Oil supply/return ducts provide the
turbocharger lubrication.
PART B:
OPERATIONS POSSlBLE
WITH ENGINE IN CAR
Camshaft and camshaft
carrier - removal and
refitting
#
Warning: Refer to the beginning
of Section 9 before starting any
work.
1Disconnect the battery, negative lead first.
2Disconnect its leads and unbolt the
distributor from the end of the camshaft, and
place it to one side.
3Disconnect the air intake hose from the
throttle valve housing.
4Disconnect the short throttle control cable
from its sector.
5Remove the throttle cable support bracket.
6Disconnect the earth leads from the
camshaft cover.
7Refer to Section 9, Part C of this
Supplement and remove the following
components.
Supplementary air valve
Inlet manifold with fuel pressure regulator
and excess pressure safety switch
Injector cooling duct
8Disconnect the wiring plug from the
Microplex ignition anti-knock sensor.
9Carry out the operations described in
Chapter 1, Section 27, paragraphs 4 to 12.
10Refitting is a reversal of removal, referring
to Section 28 of Chapter 1 for the timing belt
refitting procedure, and to Chapter 1, Sec-
tion 27, paragraphs 15 to 18.
Cylinder head -
removal and refitting#
11Carry out the operations described in
paragraphs 4 to 9 in the preceding
sub-Section, then refer to Chapter 1, Section
29, but ignore all references to the
carburettor.
12Note the distributor mounting cover.
13Four additional cylinder head bolts are
used on these engines, adjacent to the spark
plugs (photo). Note that their tightening torque
differs from the other cylinder head bolts - see
Specifications. These four bolts are tightened
13•34 Supplement: Revisions and information on later models
1 Oil pick-up strainer
2 Oil pump
3 Oil pressure relief valve
4 Oil filter cartridge
5 Main oil gallery6 Camshaft oil feed
7 Low oil pressure switch
8 Engine oil cooler
9 Filter mounting base
10 Turbocharger oil feed11 Turbocharger oil return
12 Oil pressure sender unit
13 Oil temperature sender
unit
14 Piston oil spray nozzle
Fig. 13.12 Piston oil spray nozzle locations - 1301 cc Turbo ie engine (Sec 6A)
Letters denote cylinder bore grade
Fig. 13.11 1301 cc Turbo ie engine lubrication system (Sec 6A)
6A.9 Oil pressure sender unit

separately, after the ten main bolts (see
Fig. 13.13).
Piston rings
14The piston rings comprise two
compression rings marked TOP, and an oil
control ring.
15Cross-sections and fitting details are
shown in Fig. 13.14.
Engine mountings - renewal
16The operations are essentially as
described in Section 33 of Chapter 1, but note
the design and fixings of the individual
mountings used on the turbocharged engine
(photos).
Timing belt - renewal#
17The operations described in Chapter 1,
Section 28 generally apply, but the following
differences should be noted.18Remove the engine compartment
right-hand shield. This is secured by plastic
clips. To remove a clip, push out its centre
pin.
19The TDC sensor must be unbolted to
provide room to remove and refit the timing
belt, which can be carried out without
having to remove the crankshaft pulley
(photos).
20The belt tensioner on later versions
does not incorporate a spring, but is of
eccentric centre bolt hole type. Have the
pulley bolt released, and tension the belt by
turning the pulley using a pin wrench or
circlip pliers in the two holes provided.
Keep the tension applied while the lockbolt
is tightened. Turn the crankshaft through
two complete turns, and then check the belt
tension. With moderate finger and thumb
pressure, the belt should just twist through90º when gripped at the mid-point of its
longest run (photo). Note: This 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.
Oil pump drivegear cover plate
21Due to the fact that the distributor is
driven from the end of the camshaft, the oil
pump gear does not have an extension to
drive the distributor, which would be the case
if it was mounted on the crankcase.
22The crankcase aperture is therefore
covered by a plate and gasket, together with a
wiring clip (photo).
Supplement: Revisions and information on later models 13•35
6B.13 Two of the four additional cylinder
head bolts (arrowed)
Fig. 13.14 Piston ring arrangement on the
1301 cc Turbo ie engine (Sec 6B)Fig. 13.13 Cylinder head bolt tightening
sequence on the 1301 cc Turbo ie engine
(Sec 6B)
6B.22 Distributor drive hole cover plate
(arrowed)6B.20 Belt tensioner pulley locknut
(arrowed)6B.19B Removing the timing belt
6B.19A Removing the TDC sensor6B.16B Engine/transmission right-hand
mounting6B.16A Engine/transmission centre
mounting
13

Engine oil cooler -
removal and refittingÁ
23The oil cooler is mounted behind the front
bumper/spoiler (photo).
24Disconnect the oil flow and return hoses,
either from the cooler or the oil filter cartridge
mounting base. Be prepared for some
leakage of oil (photos).
25Unscrew the mounting bolts and remove
the oil cooler heat exchanger (photo).
26When refitting, make sure that the banjo
union sealing washers are in good condition.
PART C: ENGINE REMOVAL,
DISMANTLING, REASSEMBLY
AND REFITTING
Engine/transmission -
removal and separation
#
Warning: Refer to the beginning
of Section 9 before starting any
work.
1Refer to Chapter 1, Section 35, and carry
out the operations described in paragraphs 1
to 11.
2Disconnect the excessive air pressure
switch from the inlet manifold.
3Disconnect the ducts and remove the
airflow meter.
4Disconnect the leads from the spark plugs
and the distributor LT connector, and unbolt
and remove the distributor from the rear end
of the camshaft carrier.
5Disconnect the fuel return hose from the
pressure regulator. 6Disconnect the fuel inlet hose from the
injector rail.
7Disconnect the wiring plugs from the fuel
injectors.
8Disconnect the leads from the oil pressure
sender unit, the low oil pressure switch and
the coolant temperature switch.
9Remove the hose/pipe assemblies from the
intercooler.
10Disconnect the throttle control rod at the
balljoint.
11Disconnect the hoses and ducts from the
turbocharger and the mechanical bypass
valve.
12Disconnect the leads from the engine
speed and anti-knock sensors.
13Raise the front of the car and support it
securely. As the engine/transmission will
eventually be lowered to the floor, make sure
that there is sufficient clearance under the
front end for the assembly to be withdrawn. If
the car is over an inspection pit, then the car
need only be raised enough to lift the
roadwheels from the floor.
14Remove the front roadwheels.
15Disconnect the transmission earth cable.
16Working under the car, remove the engine
shields from under the wheel arches.
17Remove the engine oil cooler, and the
intercooler.
18Unscrew the fixing screws and disconnect
the driveshafts from the flanges at the
transmission final drive. The right-hand
driveshaft will not release until the upper bolt
on the suspension strut-to-hub carrier clamphas been removed, and the hub assembly
tilted downwards.
19Disconnect the exhaust downpipe from
the manifold, and then remove the front
section of the exhaust system.
20Disconnect the coolant return pipe from
the turbocharger.
21Disconnect the gearchange control rods
from the transmission selector rod. Do this by
unscrewing the self-locking nut from the bolt
which connects the clevis fork.
22Attach suitable lifting gear to the engine
lifting eyes, and take the weight of the
engine/transmission.
23Disconnect the left-front, centre-rear and
the right-hand engine/transmission mountings.
Do this by removing the bolts from the
diamond-shaped mounting plates there is no
need to disturb the flexible mounting centre
bolts.
24Lower the engine/transmission to the floor
and withdraw it from under the car.
25Carry out the operations described in
Chapter 1, Section 35, paragraphs 27 to 31.
Engine dismantling and
reassembly
26The operations are essentially as
described for the 1301 cc engine in Chapter 1,
but reference must be made to Sections 9
and 10 of this Chapter for the procedures for
removing and refitting the components of the
fuel injection, turbocharger and ignition
systems.
Engine/transmission -
reconnection and refitting
27The operations are a reversal of those
described in paragraphs 1 to 25, but
otherwise the following (photo).
a) Tighten all nuts and bolts to the specified
torque.
b) Use a new gasket at the exhaust
downpipe-to-manifold flange.
c) Check and adjust the clutch pedal travel.
d) Refill the cooling system.
e) Refill the engine and transmission with oil.
f) Reconnect the battery, negative lead
last.
13•36 Supplement: Revisions and information on later models
6C.27 Filling the engine with oil6B.25 Oil cooler mounting bolts (arrowed)
6B.24B Connections at oil filter cartridge
mounting base6B.24A Oil cooler pipe connection
(arrowed)6B.23 Oil cooler

Initial start-up after major
overhaul
28Refer to Chapter 1, Section 45, but note
that an oil pressure gauge is fitted to indicate
oil pressure.
29Check the ignition static timing as
described in Section 10.
30Check the engine idle speed and CO level
as described in Section 9.
7 Engine-
1372 cc ie and 1372 cc
Turbo ie
PART A: GENERAL
Description
1The 1372 cc engine is similar in design to
the OHC engine fitted to the FIAT Tipo
variants. The engine is of four-cylinder, in-line,
overhead camshaft type, mounted
transversely at the front of the vehicle.
2The crankshaft runs in five main bearings.
Thrustwashers are fitted to the rear (flywheel
end) main bearing in order to control
crankshaft endfloat.
3The connecting rods are attached to the
crankshaft by horizontally split shell-type
big-end bearings. The pistons are attached to
the connecting rods by fully-floating gudgeon
pins which are secured by circlips. The
aluminium alloy pistons are fitted with three
piston rings: two compression rings and an oil
control ring.
4The camshaft is driven by a toothed belt
and operates the valves via bucket and shim
type cam followers. The camshaft is located in
a separate housing on top of the cylinder
head.
5The inlet and exhaust valves are each
closed by double valve springs, and operate
in guides pressed into the cylinder head.
6The auxiliary shaft, which is also driven by
the toothed belt, drives the oil pump.
7Lubrication is by means of a gear type
pump which draws oil through a strainer
located in the sump, and forces it through a
full-flow filter into the engine oil galleries fromwhere it is distributed to the crankshaft,
camshaft and auxiliary shaft. The big-end
bearings are supplied with oil via internal
drillings in the crankshaft. The undersides of
the pistons are cooled by oil spray nozzles
located in each main bearing location in the
crankcase.
8A crankcase ventilation system is
employed, whereby piston blow-by gases are
drawn via an oil separator into the air cleaner,
from where they are drawn into the inlet
manifold and re-burnt with fresh air/fuel
mixture.
9The 1372 cc ie engine is fitted with a Bosch
Mono-Jetronic single point fuel injection (SPi)
system. Whilst the higher performance
1372 cc Turbo ie engine is fitted with a Bosch
L3.1 (L3.2 from 1992) Jetronic multi-point
injection (MPi) system and turbocharger with
intercooler and oil cooling. The L3.2 system
models are fitted with catalytic converters.
Maintenanceª
10At the intervals specified in Section 3 or
“Routine maintenance” at the beginning of
this Manual, carry out the following tasks.
11Check the engine oil level as follows. With
the vehicle parked on level ground, and with
the engine having been stopped for a few
minutes, withdraw the oil level dipstick, wipe it
on a clean rag, and re-insert it fully. Withdraw
the dipstick again and read off the oil level
relative to the MAX and MIN marks. The oil
level should be between the marks. If the level
is at or below the MIN mark, top up through
the filler on the camshaft cover without delay
(photo). The quantity of oil required to raise
the level from MIN to MAX on the dipstick is
approximately 1.0 litre (1.8 pints). Do not
overfill.
12Renew the engine oil and filter as
described in Section 2 of Chapter 1 (photos).
13Check and if necessary adjust the valve
clearances as described in Part B of this
Section.
14Inspect the engine for signs of oil, coolant
or fuel leaks and rectify as necessary.
15Inspect the crankcase ventilation hose for
blockage or damage. Clean or renew as
necessary.
16Check the condition and tension of thetiming belt as described in Part B of this
Section.
17Renew the timing belt as described in
Part B of this Section.
PART B:
OPERATIONS POSSlBLE
WITH ENGINE IN CAR
Valve clearances -
checking and adjustment#
1It is important to ensure that the valve
clearances are set correctly, as incorrect
clearances will result in incorrect valve timing
thus affecting engine performance.
2The clearances must be checked and
adjusted with the engine cold.
3On the ie engine, refer to Section 9 in this
Chapter for details and remove the air cleaner
unit.
4On the ie engine disconnect the crankcase
ventilation hose from the injector unit and
position the hose out of the way.
5On Turbo ie engines, loosen off the clips
and remove the air hose to the inlet manifold
(above the camshaft cover).
6On Turbo ie engines, disconnect the
accelerator cable from the throttle housing
and the support bracket on the camshaft
cover.
7Unscrew the securing nuts and washers
and remove the camshaft cover, noting that
on later models two of the nuts also secure
the hose clip assembly. Recover the gasket.
8Numbering from the front (timing belt) end
of the engine, the exhaust valves are 1, 4, 5
and 8, and the inlet valves are 2, 3, 6 and 7.
Supplement: Revisions and information on later models 13•37
7A.12B Engine oil filter removal using a
strap wrench - 1372 cc engine7A.12A Engine sump drain plug - 1372 cc
engine7A.11 Topping up the engine oil level -
1372 cc engine
Fig. 13.15 Engine oil level dipstick location
and level markings on the 1372 cc ie and
Turbo ie engines (Sec 7A)
13