1983 FIAT UNO ESP

9Turn the engine clockwise using a suitable
socket on the crankshaft pulley bolt, until the
exhaust valve of No 1 cylinder (valve No 1) is
fully closed; ie the cam lobe is pointing
directly upwards. Alternatively, the engine can
be turned by jacking up one front corner of
the vehicle and supporting it securely on an
axle stand (apply the handbrake and chock
the diagonally-opposite rear wheel before
jacking), engaging top gear and turning the
raised roadwheel in the forward direction of
travel. In both cases, it will be easier to turn
the engine if the spark plugs are removed, but
if this is done, take care not to allow dirt or
other foreign matter to enter the spark plug
holes.
10Insert a feeler gauge of the correct
thickness between the cam follower shim and
the heel of the No 1 cam lobe (photo). If
necessary, increase or reduce the thickness
of the feeler gauge until it is a firm sliding fit.
Record the thickness of the feeler gauge,
which will represent the valve clearance for
this particular valve.
11Turn the crankshaft, and repeat the
procedure for the remaining valves, recording
their respective clearances. Note that the
clearance for inlet and exhaust valves differs.
12If a clearance is incorrect, the relevant
cam follower shim must be removed, and a
thicker or thinner shim must be fitted to
achieve the correct clearance. To remove a
shim proceed as follows.
13Turn the crankshaft until the relevant cam
lobe is pointing directly upwards.
14The cam follower must now be depressed
in order to extract the shim. FIAT special tool
No 1860642000 is available for this purpose,
but alternatively a suitable tool can be
improvised (photo). The tool should locate on
the rim of the cam follower, leaving enough
room for the shim to be prised out by means
of the cut-outs provided in the cam follower
rim. Depress the cam follower by turning the
crankshaft as described previously until the
relevant cam lobe is pointing directly
downwards, then fit the tool between the
camshaft and the edge of the cam follower to
retain the cam follower in the depressed
position.
15Ensure that the tool is securely located, asthere is a risk of personal injury if the tool is
dislodged whilst the cam follower is
depressed, then turn the crankshaft until the
relevant cam lobe is pointing directly
upwards, leaving sufficient room to extract
the shim (photo). A pair of angle-nosed pliers
will greatly ease removal of the shim.
16Once the shim has been extracted,
establish its thickness. The thickness in mm
should be stamped into the face of the shim,
although it is possible for wear to obliterate
the number, in which case the use of a metric
micrometer is the only way to accurately
establish the thickness.
17Refer to the clearance recorded for the
valve concerned. If the clearance recorded
was larger than that specified, a thicker shim
must be fitted, and if the clearance recorded
was smaller than that specified, a thinner shim
must be fitted. The required thickness of shim
can be
calculated as follows.
Sample calculation - clearance too large:
Desired clearance (A) 0.40 mm
Measured clearance (B) 0.45 mm
Difference (B - A) + 0.05 mm
Original shim thickness 3.40 mm
Required shim thickness 3.40 + 0.05 =
3.45 mm
Sample calculation - clearance too small:
Desired clearance (A) 0.50 mm
Measured clearance (B) 0.35 mm
Difference (B - A) 0.15 mm
Original shim thickness 4.55 mm
Required shim thickness 4.55 - 0.15 =
4.40 mm
18Shims are available in thicknesses from
3.20 to 4.70 mm, in steps of 0.05 mm. Note
that if several shims have to be changed, they
can often be interchanged, thus avoiding the
need by buy more new shims than are
necessary.
19The shims should be fitted to the cam
followers with the stamped thickness marking
against the face of the cam follower.
20After fitting a shim, rotate the crankshaft
as described previously until the relevant cam
lobe is pointing directly downwards (resting
on the shim), then carefully remove the tool
used to retain the follower in the depressed
position.21Re-check each relevant valve clearance
after fitting the shim.
22On completion, where applicable, lower
the vehicle to the ground.
23Refit the camshaft cover, using a new
gasket.
24On the ie engine, reconnect the hoses and
refit the air cleaner unit.
25On the Turbo ie engine, reconnect the air
hose and the accelerator cable.
Timing belt tensioner
and sprockets -
removal and refitting
#
Note: The timing belt must be renewed after
removal: never refit a used drivebelt. When
fitting the new timing belt it will need to be
correctly tensioned and to achieve this the
manufacturers specify the use of special tools
1860745200 (18760745300 on Turbo model)
and 1860745100. If these tools are not readily
available, an approximate setting can be
made, but in this instance it is strongly
recommended that the car be taken to a FIAT
dealer at the earliest opportunity to have the
belt tension checked and correctly set using
the recommended tools.
26Loosen off the front right-hand side wheel
bolts, then raise and support the car at the
front end on axle stands. Remove the front
right-hand roadwheel.
27Remove the underwing shield from the
right-hand wheel arch to allow access to the
lower timing cover and alternator fixings (photo).
13•38 Supplement: Revisions and information on later models
7B.27 Underwing shield (A) showing
central compression pin (B) and retaining
clip (C). Drive pin through clip to remove
7B.15 Removing a shim from a cam
follower7B.14 Special tool for retaining cam
follower in depressed position7B.10 Measuring a valve clearance
(No 2 valve shown)

crankshaft after the pulley securing nut has
been removed. Recover the Woodruff key
from the end of the crankshaft if it is loose
(photo).
44To remove the auxiliary shaft sprocket, a
suitable tool must be used to hold the
sprocket stationary as the securing bolt is
loosened (the bolt is extremely tight). In the
workshop, a “scissors” style tool was
improvised, using two pieces of steel bar
joined together by a pivot bolt, with their ends
bent through a right-angle to engage securely
between the teeth on the sprocket - see photo
7B.46.
45Unscrew the sprocket bolt, and recover
the washer, then withdraw the sprocket from
the end of the auxiliary shaft (photo). If thesprocket is tight, carefully lever it from the
shaft using two screwdrivers.
46Refit the auxiliary shaft sprocket, making
sure that the lug on the end of the shaft
engages with the hole in the sprocket, then
tighten the securing bolt to the specified
torque (ensure that the washer is in place
under the bolt head). Prevent the sprocket
from turning as during removal (photo).
47Where applicable, refit the Woodruff key
to the end of the crankshaft, then refit the
crankshaft sprocket with the flanged side
against the oil seal housing (photo).
48Refit the camshaft sprocket to the end of
the camshaft, making sure that the lug on the
end of the shaft engages with the hole in the
sprocket, then refit the thrust washer, plainwasher, and bolt, and tighten the bolt to the
specified torque. Prevent the camshaft from
turning as during removal (photo).
49Refit the belt tensioner pulley assembly,
ensuring that the washer is in place under the
securing nut, but do not fully tighten the nut at
this stage.
50Before refitting the new timing belt into
position, first ensure that the crankshaft and
camshaft sprocket timing marks are still
aligned as described in paragraph 30 (photo).
51If the new timing belt has two timing marks
on its outer face they must align with the
corresponding marks on the crankshaft and
camshaft sprockets. Do not distort or bend the
belt any more than is necessary during its
fitting or its structural fibres may be damaged.
52Refit the belt around the sprockets and
the tensioner pulley, starting at the crankshaft
sprocket. One of the timing index marks must
align with the scribed mark on the lower edge
of the crankshaft sprocket (opposite the
Woodruff key) whilst the second mark must
align with the timing marks of the camshaft
and rear timing belt cover (photos).
53With the belt fitted over the sprockets and
correctly aligned, temporarily refit the
crankshaft pulley nut (tightening it to its full
torque wrench setting) and then adjust the
timing belt tension.
Approximate setting
54The timing belt tension can be checked
approximately by twisting it between the
13•40 Supplement: Revisions and information on later models
7B.52B Timing belt mark aligned with
scribed mark on crankshaft sprocket
(arrowed)7B.52A Timing belt refitted over the
sprockets and tensioner7B.50 Crankshaft at TDC with key and
timing mark aligned (arrowed)
7B.48 Tightening the crankshaft sprocket
bolt7B.47 Refitting the crankshaft sprocket
7B.46 Tightening the auxiliary shaft
sprocket bolt7B.45 Withdrawing the auxiliary shaft
sprocket7B.43 Remove the crankshaft Woodruff
key if it is loose

61Refer to Part B of this Section for details
and remove the flywheel.
62Refer to the previous sub-Section for
details and remove the auxiliary shaft.
63Refer to Part B of this Section for details
and remove the sump.
64Refer to Part B of this Section for details
and remove the oil pump unit.
65Refer to Part B of this Section for details
and remove the front and rear crankshaft oil
seals.
66Refer to Part B of this Section and remove
the piston/connecting rod assemblies.
67Refer to Part B of this Section for details
and remove the crankshaft and main bearing
assemblies.
Crankshaft and main
bearings - removal#
68Unscrew the securing bolts and remove
the front and rear crankshaft oil seal housings.
Recover the gaskets.
69Check the main bearing caps for identifi-
cation marks and if necessary use a
centre-punch to identify them. Normally the
caps have identifying notches cut into their
top face nearest the timing belt end of the
engine, with the exception of No 5 cap
(flywheel end) which has no marking (photo).
70Before removing the crankshaft, check
that the endfloat is within the specified limits.
Ideally a dial gauge should be used, but
alternatively feeler gauges can be used as
follows. Push the crankshaft as far as possible
towards the timing end of the engine, and
using a feeler gauge, measure the gap
between the rear face of the flywheel
mounting flange on the crankshaft and the
outer face of the thrust washer (photo). Now
push the crankshaft as far as possible in the
opposite direction and take the same
measurement again. The difference between
the two measurements is the crankshaft
endfloat. If the endfloat is outside the
specified limits, new thrustwashers will be
required.
71Unscrew the bolts and tap off the main
bearing caps complete with bearing shells. If
the bearing shells are to be re-used, tape
them to their respective caps.
72Lift the crankshaft from the crankcase.
73Extract the bearing shells from thecrankcase, keeping them identified for
location if they are to be re-used, and recover
the thrust washers from No. 5 main bearing
location.
Engine components -
examination and
renovation
#
74With the engine completely stripped,
clean all the components and examine them
for wear. Each part should be checked and
where necessary renewed or renovated as
described elsewhere in this Section. Renew
main and big-end bearing shells as a matter of
course, unless it is known that they have had
little wear and are in perfect condition.
75If in doubt as to whether to renew a
component which is still just serviceable,
consider the time and effort which will be
incurred should the component fail at an early
date. Obviously the age and expected life of
the vehicle must influence the standards
applied.
76Gaskets, oil seals and O-rings must all be
renewed as a matter of course. FIAT specify
that the main cylinder head bolts should be
renewed after they have been used (ie
tightened) four times - if in any doubt as to the
number of times the bolts have been used,
renew them in any case as a precaution
against possible failure.
77Take the opportunity to renew the engine
core plugs while they are easily accessible.
Knock out the old plugs with a hammer and
chisel or punch. Clean the plug seats, smearthe new plugs with sealant and tap them
squarely into position.
78Clean and examine the cylinder block as
described in paragraphs 2 to 7 of Section 18,
Chapter 1.
79If the auxiliary shaft bushes are
excessively worn or are oval, they must be
renewed. When the new bushes are installed,
they may need to be reamed to suit. The
renewal of the auxiliary shaft bushes is
therefore best entrusted to an engine
reconditioner or FIAT dealer. When the
bushes are renewed, ensure that the oil hole
in each bush is aligned with the oil channel in
the cylinder block.
PART D: ENGINE
REASSEMBLY
Reassembly - general
1Refer to Chapter 1, Section 19.
Crankshaft and main
bearings - refitting#
2Ensure that the crankcase and crankshaft
are thoroughly clean, and that the oilways are
clear. If possible, blow through the oil drillings
with compressed air, and inject clean engine
oil into them.
3Unless they are virtually new, the old main
bearing shells should be renewed. Failure to
do so is a false economy.
4If new bearing shells are being fitted, wipe
away all traces of protective grease.
5Note that there is a tag on the back of each
bearing shell, which engages with a groove in
the relevant seat in the crankcase or bearing
cap.
6Wipe clean the bearing shell locations in the
crankcase with a non-fluffy rag, then lubricate
them and fit the five upper halves of the
bearing shells to their seats. Note that the
centre (No. 3) bearing shell is plain, whereas
all the other shells have oil grooves (photos).
7Fit the thrustwashers to the No. 5 main
bearing shell location, with the grooved side
of each washer facing away from the face of
the cylinder block - ie towards the thrust face
of the crankshaft (photos).
8Wipe the bearing shell locations in the
13•52 Supplement: Revisions and information on later models
7D.6B . . . all others have oil groove7D.6A No. 3 main bearing shell is plain . . .
7C.70 Measuring crankshaft endfloat using
feeler gauge method7C.69 Identification notches on No. 3 main
bearing cap

47Loosen off the switch-to-column clamp
screw, disconnect the wiring connectors to
the switch and withdraw the switch from the
column (photos).
48Refit in the reverse order of removal, but
ensure that the lug of the switch aligns with
the slot in the column as it is fitted into
position. Check for satisfactory operation of
the switches on completion.
Instrument panel
(Turbo ie models) -
removal and refitting
Á
49The instrument panel on these models
incorporates an engine oil pressure gauge
and a turbo boost gauge. The latter is
connected directly to the inlet manifold.
50Apart from disconnecting the boost gauge
rubber hose, the instrument panel removal
and refitting procedure is as described in
Chapter 9 for the 1301 cc model or from
paragraph 57 in this Section for the 1372 cc
model.
51A digital electronic instrument panel is
available as an option on Turbo ie models.
The removal and refitting procedures differ
from analogue instrument panels in respect of
the electrical connections - a speedometer
drive cable is not used.
Facia-mounted switches
(1301 cc Turbo ie model) -
removal and refitting
Á
52Disconnect the battery.53Insert a thin-bladed screwdriver into the
joint between the switch block and the switch
block housing, to depress the plastic retaining
tabs. Do this carefully, otherwise the switch
block or casing will be damaged.
54Withdraw the switch block. Individual
switches can now be pushed out of the block.
Fibre optics are used to illuminate some
switches, these simply pull out of their
sockets (photos). The illumination bulb is
located on a crossmember found behind the
instrument pack. Removal of instruments/top
cover allows access.
55The switch housing can be removed after
extracting the fixing screws (photos).
56Refitting is a reversal of removal.
Instrument panel
(later models) -
removal and refitting
Á57Disconnect the battery negative lead.
58Unscrew and remove the two instrument
panel-to-facia retaining screws (photo).
59Remove the lower facia trim panel, which
is secured by two screws and a nut. Reach up
to the rear of the instrument panel to
disconnect the speedometer cable, then push
the panel from its recess in the facia.
Disconnect the multi-connectors from the rear
face of the panel and withdraw it (photo).
60Refit in the reverse order of removal.
Ensure that the speedometer cable is fully
engaged as the unit is refitted into position.
Supplement: Revisions and information on later models 13•107
15.47B . . . and remove the column switch15.47A Undo the retaining screw . . .15.45C . . . and the lower column
shroud . . .
15.58 Remove the retaining screws . . .15.55B Facia switch housing inner screw
removal on the 1031 cc Turbo ie model
15.54B Disconnecting a fibre optic cable
from its holder on the 1301 cc Turbo ie
model15.54A Switch block withdrawal on the
1301 cc Turbo ie model
15.55A Facia switch housing lower screw
removal on the 1301 cc Turbo ie model
13

Auxiliary control panel
(later models) -
removal and refitting
Á
61Disconnect the battery negative lead.
62Insert the flat of a screwdriver under the
trim piece at the end of the auxiliary panel as
shown and prise it free. Repeat the procedure
and remove the trim piece at the other end of
the panel (photo).
63Undo the retaining screws, withdraw the
panel from the facia. Disconnect the wiring
connectors from the panel switches to
remove the panel completely (photo).
64A switch bulb can be renewed by
untwisting the holder and removing the holder
and bulb.
65A switch unit can be removed from the
panel by unscrewing the four retaining screws.66Refitting is a reversal of the removal
procedure. Ensure that the wiring connections
are securely made and check for satisfactory
operation of the switches on completion.
Heater control panel
(later models) -
removal and refitting
Á
67Disconnect the battery negative lead.
68Pull free the heater/fresh air and blower
control knobs (photo).
69Undo the two retaining screws and
withdraw the control panel from the facia
(photos). Detach the wiring connectors from the
panel illumination lights and remove the panel.
70Refitting is a reversal of the removal
procedure. Ensure that the wiring connections
are securely made and on completion check
that the operation of the controls is satisfactory.
Trip master Á
71This electronic instrument is fitted into the
check panel of 1100SL and 1300SL models
from 1986.
72The device provides information on fuel
consumption, range, speed and elapsed time.
73With the ignition key turned to MAR,
figures are displayed in respect of the last
journey - average fuel consumption, average
speed and elapsed time (up to switching off
the ignition).
74As soon as the engine is started, the
instrument processes the current values to
include fuel consumption, range and the
actual time. 75Fuel consumption is only displayed when
the road speed exceeds 8.0 km/h (5.0 mph).
76The fuel range is only displayed after a
road speed of between 25.0 and 70.0 km/h
(15.0 to 44.0 mph) has been maintained for at
least 90 seconds or at higher speeds for
22 seconds.
77A reset button is provided, also a display
change button (from instant to average or
total values). Should the instrument reading
exceed 99 hours, 59 minutes or 1000 km
(622 miles) depressing the display change
button will display all zeros. Depress button E
to resume normal function.
78Refer to the end of the manual for a wiring
diagram of the check panel, incorporating the
trip master.
Interior roof mounted spotlamp,
switch and/or clock -
removal and refitting
Á
79Disconnect the battery negative lead.
80Prise free the lamp unit from its aperture
in the roof panel using a thin-bladed
screwdriver. The lamp bulb can be inspected
by untwisting the holder and withdrawing it
from the rear of the unit (photos). Extract the
bulb from the holder if it requires renewal.
81To remove the lamp switch from the
panel, reach through the lamp aperture and
press it free from the roof panel (photo).
Detach the wiring connectors.
82To remove the clock, reach through the
lamp aperture and undo the retaining screws
(photo). Withdraw the clock and detach the
wiring connectors.
13•108 Supplement: Revisions and information on later models
15.69B . . . and withdraw the heater control
panel15.69A . . . undo the retaining screws
(arrowed)15.68 Remove the control knobs . . .
15.63 . . . and withdraw the auxiliary
control panel
15.62 Prise free the trim covers for access
to retaining screws . . .15.59B . . . and disconnect the
speedometer cable15.59A . . . withdraw the instrument
panel . . .

Fault FindingREF•9
REF
Introduction
The vehicle owner who does his or her own
maintenance according to the recommended
schedules should not have to use this section
of the manual very often. Modern component
reliability is such that, provided those items
subject to wear or deterioration are inspected
or renewed at the specified intervals, sudden
failure is comparatively rare. Faults do not
usually just happen as a result of sudden
failure, but develop over a period of time.
Major mechanical failures in particular are
usually preceded by characteristic symptoms
over hundreds or even thousands of miles.
Those components which do occasionally fail
without warning are often small and easily
carried in the vehicle.
With any fault finding, the first step is to
decide where to begin investigations.
Sometimes this is obvious, but on other
occasions a little detective work will be
necessary. The owner who makes half a
dozen haphazard adjustments or
replacements may be successful in curing a
fault (or its symptoms), but he will be none the
wiser if the fault recurs and he may well have
spent more time and money than was
necessary. A calm and logical approach will
be found to be more satisfactory in the long
run. Always take into account any warning
signs or abnormalities that may have been
noticed in the period preceding the fault –
power loss, high or low gauge readings,
unusual noises or smells, etc – and remember
that failure of components such as fuses or
spark plugs may only be pointers to some
underlying fault.
The pages which follow here are intended
to help in cases of failure to start or
breakdown on the road. There is also a Fault
Diagnosis Section at the end of each Chapter
which should be consulted if the preliminary
checks prove unfruitful. Whatever the fault,
certain basic principles apply. These are as
follows:Verify the fault. This is simply a matter of
being sure that you know what the symptoms
are before starting work. This is particularly
important if you are investigating a fault for
someone else who may not have described it
very accurately.
Don’t overlook the obvious. For example,
if the vehicle won’t start, is there petrol in the
tank? (Don’t take anyone else’s word on this
particular point, and don’t trust the fuel gauge
either!) If an electrical fault is indicated, look
for loose or broken wires before digging out
the test gear.
Cure the disease, not the symptom.
Substituting a flat battery with a fully charged
one will get you off the hard shoulder, but if
the underlying cause is not attended to,the
new battery will go the same way. Similarly,
changing oil-fouled spark plugs for a new set
will get you moving again, but remember that
the reason for the fouling (if it wasn’t simply an
incorrect grade of plug) will have to be
established and corrected.
Don’t take anything for granted.
Particularly, don’t forget that a ‘new’
component may itself be defective (especially
if it’s been rattling round in the boot for
months), and don’t leave components out of a
fault diagnosis sequence just because they
are new or recently fitted. When you do finally
diagnose a difficult fault, you’ll probably
realise that all the evidence was there from
the start.
Electrical faults
Electrical faults can be more puzzling than
straightforward mechanical failures, but they
are no less susceptible to logical analysis if
the basic principles of operation are
understood. Vehicle electrical wiring exists in
extremely unfavourable conditions – heat,
vibration and chemical attack and the first
things to look for are loose or corroded
connections and broken or chafed wires,especially where the wires pass through holes
in the bodywork or are subject to vibration.
All metal-bodied vehicles in current
production have one pole of the battery
‘earthed’, ie connected to the vehicle
bodywork, and in nearly all modern vehicles it
is the negative (–) terminal. The various
electrical components – motors, bulb holders,
etc – are also connected to earth, either by
means of a lead or directly by their mountings.
Electric current flows through the component
and then back to the battery via the
bodywork. If the component mounting is
loose or corroded, or if a good path back to
the battery is not available, the circuit will be
incomplete and malfunction will result. The
engine and/or gearbox are also earthed by
means of flexible metal straps to the body or
subframe; if these straps are loose or missing,
starter motor, generator and ignition trouble
may result.
Assuming the earth return to be
satisfactory, electrical faults will be due either
to component malfunction or to defects in the
current supply. Individual components are
dealt with in Chapter 9. If supply wires are
broken or cracked internally this results in an
open-circuit, and the easiest way to check for
this is to bypass the suspect wire temporarily
with a length of wire having a crocodile clip or
suitable connector at each end. Alternatively,
a 12V test lamp can be used to verify the
presence of supply voltage at various points
along the wire and the break can be thus
isolated.
If a bare portion of a live wire touches the
bodywork or other earthed metal part, the
electricity will take the low-resistance path
thus formed back to the battery: this is known
as a short-circuit. Hopefully a short-circuit will
blow a fuse, but otherwise it may cause
burning of the insulation (and possibly further
short-circuits) or even a fire. This is why it is
inadvisable to bypass persistently blowing
fuses with silver foil or wire.

Glossary of Technical TermsREF•15
REF
GGapThe distance the spark must travel in
jumping from the centre electrode to the side
electrode in a spark plug. Also refers to the
spacing between the points in a contact
breaker assembly in a conventional points-
type ignition, or to the distance between the
reluctor or rotor and the pickup coil in an
electronic ignition.
GasketAny thin, soft material - usually cork,
cardboard, asbestos or soft metal - installed
between two metal surfaces to ensure a good
seal. For instance, the cylinder head gasket
seals the joint between the block and the
cylinder head.
GaugeAn instrument panel display used to
monitor engine conditions. A gauge with a
movable pointer on a dial or a fixed scale is an
analogue gauge. A gauge with a numerical
readout is called a digital gauge.
HHalfshaftA rotating shaft that transmits
power from the final drive unit to a drive
wheel, usually when referring to a live rear
axle.
Harmonic balancerA device designed to
reduce torsion or twisting vibration in the
crankshaft. May be incorporated in the
crankshaft pulley. Also known as a vibration
damper.
HoneAn abrasive tool for correcting small
irregularities or differences in diameter in an
engine cylinder, brake cylinder, etc.
Hydraulic tappetA tappet that utilises
hydraulic pressure from the engine’s
lubrication system to maintain zero clearance
(constant contact with both camshaft and
valve stem). Automatically adjusts to variation
in valve stem length. Hydraulic tappets also
reduce valve noise.
IIgnition timingThe moment at which the
spark plug fires, usually expressed in the
number of crankshaft degrees before the
piston reaches the top of its stroke.
Inlet manifoldA tube or housing with
passages through which flows the air-fuel
mixture (carburettor vehicles and vehicles with
throttle body injection) or air only (port fuel-
injected vehicles) to the port openings in the
cylinder head.
JJump startStarting the engine of a vehicle
with a discharged or weak battery by
attaching jump leads from the weak battery to
a charged or helper battery.
LLoad Sensing Proportioning Valve (LSPV)A
brake hydraulic system control valve that
works like a proportioning valve, but also
takes into consideration the amount of weight
carried by the rear axle.
LocknutA nut used to lock an adjustment
nut, or other threaded component, in place.
For example, a locknut is employed to keep
the adjusting nut on the rocker arm in
position.
LockwasherA form of washer designed to
prevent an attaching nut from working loose.
MMacPherson strutA type of front
suspension system devised by Earle
MacPherson at Ford of England. In its original
form, a simple lateral link with the anti-roll bar
creates the lower control arm. A long strut - an
integral coil spring and shock absorber - is
mounted between the body and the steering
knuckle. Many modern so-called MacPherson
strut systems use a conventional lower A-arm
and don’t rely on the anti-roll bar for location.
MultimeterAn electrical test instrument with
the capability to measure voltage, current and
resistance.
NNOxOxides of Nitrogen. A common toxic
pollutant emitted by petrol and diesel engines
at higher temperatures.
OOhmThe unit of electrical resistance. One
volt applied to a resistance of one ohm will
produce a current of one amp.
OhmmeterAn instrument for measuring
electrical resistance.
O-ringA type of sealing ring made of a
special rubber-like material; in use, the O-ring
is compressed into a groove to provide the
sealing action.
Overhead cam (ohc) engineAn engine with
the camshaft(s) located on top of the cylinder
head(s).Overhead valve (ohv) engineAn engine with
the valves located in the cylinder head, but
with the camshaft located in the engine block.
Oxygen sensorA device installed in the
engine exhaust manifold, which senses the
oxygen content in the exhaust and converts
this information into an electric current. Also
called a Lambda sensor.
PPhillips screwA type of screw head having a
cross instead of a slot for a corresponding
type of screwdriver.
PlastigageA thin strip of plastic thread,
available in different sizes, used for measuring
clearances. For example, a strip of Plastigage
is laid across a bearing journal. The parts are
assembled and dismantled; the width of the
crushed strip indicates the clearance between
journal and bearing.
Propeller shaftThe long hollow tube with
universal joints at both ends that carries
power from the transmission to the differential
on front-engined rear wheel drive vehicles.
Proportioning valveA hydraulic control
valve which limits the amount of pressure to
the rear brakes during panic stops to prevent
wheel lock-up.
RRack-and-pinion steeringA steering system
with a pinion gear on the end of the steering
shaft that mates with a rack (think of a geared
wheel opened up and laid flat). When the
steering wheel is turned, the pinion turns,
moving the rack to the left or right. This
movement is transmitted through the track
rods to the steering arms at the wheels.
RadiatorA liquid-to-air heat transfer device
designed to reduce the temperature of the
coolant in an internal combustion engine
cooling system.
RefrigerantAny substance used as a heat
transfer agent in an air-conditioning system.
R-12 has been the principle refrigerant for
many years; recently, however, manufacturers
have begun using R-134a, a non-CFC
substance that is considered less harmful to
the ozone in the upper atmosphere.
Rocker armA lever arm that rocks on a shaft
or pivots on a stud. In an overhead valve
engine, the rocker arm converts the upward
movement of the pushrod into a downward
movement to open a valve.
Adjusting spark plug gap
Plastigage
Gasket

F
Facia - 12•10, 13•107
Fan -2•3, 13•57, 13•71, 13•84
Fast idle adjustment -3•7, 3•9, 3•10, 3•11,
13•64
Fault finding- REF`•9et seq
Fault finding - braking system -8•9
Fault finding - clutch -5•3
Fault finding - cooling and heating systems
-2•8
Fault finding - driveshafts and hubs -7•6
Fault finding - Econometer -9•12
Fault finding - electrical system -9•14,
REF•9
Fault finding - engine -1•35, 1•36, 2•8,
3•13, 4•9, 13•92, REF•10, REF•11
Fault finding - fuel system -3•9, 3•13,
13•84
Fault finding - ignition system -4•9,
REF•11
Fault finding - Microplex ignition system -
13•92
Fault finding - steering - 10•4
Fault finding - suspension - 11•6
Fault finding - transmission -6•4
Fault finding - turbocharger system - 13•84
Filling - 12•3
Final drive output shafts - 13•94
Fire -0•5
Float adjustment -3•7, 3•8, 3•10, 3•11,
13•64, 13•66
Flywheel -1•19, 1•21, 1•31, 13•46, 13•53
Fog lamps - 13•106
Fuel evaporation control system - 13•78
Fuel filter - 13•67, 13•72, 13•74, 13•79
Fuel gauge fault -9•14
Fuel injection electronic control unit (ECU)
- 13•77
Fuel injection system - 13•68, 13•69
Fuel injection system fault finding - 13•84
Fuel injectors - 13•69, 13•70, 13•71, 13•76,
13•77, 13•81, 13•84
Fuel level transmitter -3•5
Fuel pressure regulator - 13•70
Fuel pump -3•5, 13•61, 13•69, 13•72,
13•76, 13•80, 13•81
Fuel rail - 13•70, 13•81
Fuel system-3•1et seq, 13•60, REF•4
Fuel system fault finding -3•9, 3•13
Fuel tank -3•5, 13•61, 13•72
Fume or gas intoxication -0•5
Fuses -9•5, 13•105
G
Gaiters -7•2, 10•2, 13•98
Gashes in bodywork - 12•2
Gaskets -1•20
Gearbox - SeeTransmission
Gearchange lever -6•2
Gearchange linkage - 13•94, 13•95
Glossary of technical terms- REF•13et seq
Grille - 12•3, 13•113
H
Handbrake -8•8, 8•9, REF•1
Handles - 12•11
HC emissions - REF•4
Headlamp -9•6, 9•7, 13•105, 13•106
Heated tailgate window -9•10
Heater -2•5, 2•6, 13•58, 13•59, 13•108
Heater fault -2•8
Horn -9•6, 13•106
Horn fault -9•14
HT leads - 13•92
Hubs -7•3, 7•4, 11•3
Hydraulic hoses and pipes -8•6
Hydraulic system -8•7
Hydrofluoric acid -0•5
I
Idle speed adjustment -3•7, 13•62, 13•65,
13•68, 13•75, 13•79
Idling fault -1•36, 3•13, 13•84
Ignition coil - 13•86, 13•90, 13•91
Ignition switch -4•8
Ignition system-4•1et seq, 13•85
Ignition system fault finding -4•9, 9•14,
REF•11
Ignition unit - 13•89
Indicators -9•7
Injectors - 13•69, 13•70, 13•71, 13•76,
13•77, 13•81, 13•84
Inlet manifold - 13•70, 13•77, 13•80
Instrument panel -9•8, 13•107
Intercooler - 13•84
Interior lamps -9•5, 9•8
Introduction to the Fiat Uno -0•4
J
Jacking -0•8
Joint mating faces and gaskets - REF•8
Jump starting -0•7
L
Lambda sensor - 13•82
Lamps -9•6, 9•7, 9•8
Leaks -0•9, 1•36, 13•84
LED (light emitter diode) -9•12
Lights fault -9•14
Locknuts,locktabs and washers - REF•8
Locks -9•11, 10•4, 12•4, 12•6, 12•7,
13•109
Loudspeakers -9•11
Lubricants and fluids -0•13
M
Magnetic impulse generator winding -
13•86
Main bearings -1•20, 1•30, 13•52
Maintenance -0•10, 13•18
Manifolds -3•12, 13•70, 13•77, 13•80
Master cylinder -8•5, 13•103, 13•93
Microplex ignition system - 13•86, 13•89Microplex ignition system fault finding -
13•92
Mirrors - 12•11, 13•111, REF•1
Misfire -1•35, 4•9, REF•11
Mixture adjustment -3•7, 13•62, 13•65,
13•68, 13•75, 13•79
MOT test checks- REF•1et seq
Mountings -1•13, 1•27, 13•26, 13•35,
13•49
N
Needle valve - 13•66
Number plate lamp -9•7
O
Oil cooler - 13•36
Oil filter -1•8
Oil level sensor - 13•110, 13•111
Oil pressure fault -1•36, REF•11
Oil pump -1•13, 1•19, 1•22, 1•26, 1•29,
13•24, 13•30, 13•35, 13•46, 13•53
Oil seals -1•20, 13•41, 13•44, 13•45,
13•94, REF•8
Oil,engine -0•6, 0•13, 1•3, 1•4, 1•8
Oil,transmission -0•6, 0•13, 6•1, 13•14,
13•95
Overheating -2•8, 4•9, REF•11
P
Pad wear sensor - 13•110
Pads -8•2, 13•100, 13•101
Parking lamp -9•7
Pedals -5•2, 8•9, 13•92, 13•102
Pinking -1•36, 13•84, REF•11
Pistons -1•12, 1•18, 1•22, 1•26, 1•30,
13•25, 13•26, 13•30, 13•35, 13•47,
13•48, 13•53
Plastic components - 13•111
Points -4•2, 4•3
Poisonous or irritant substances -0•5
Power module - 13•90
Pre-ignition -1•36, 13•84, REF•11
Pressure regulating valve -8•6, 13•102
Pressure sensor - 13•86
R
Radiator -2•3, 12•3, 13•57, 13•113
Radio -9•10, 13•110
Rear lamp cluster -9•7
Regulator (voltage) -9•4
Regulator (window) - 12•7
Relays -9•5, 13•71, 13•105
Repair procedures - REF•8
Respraying - 12•3
Rocker cover - 13•19
Rockers -1•19
Roof rack - 12•11
Routine maintenance -0•10, 13•18
Rust holes in bodywork - 12•2
REF•18Index