1983 FIAT UNO maintenance

Contents
LIVING WITH YOUR FIAT UNO
IntroductionPage 0•4
Safety First!Page 0•5
General dimensions, weights and capacities Page0•6
Roadside Repairs
Jump startingPage0•7
Jacking, towing and wheel changing Page0•8
Identifying leaksPage0•9
Routine Maintenance and Servicing
Maintenance schedule (also see Chapter 13)Page0•10
Recommended Lubricants and Fluids Page0•13
Conversion factorsPage0•14

0•10Routine maintenance
Maintenance is essential for ensuring safety and desirable for the
purpose of getting the best in terms of performance and economy
from the car. Over the years the need for periodic lubrication has been
greatly reduced if not totally eliminated. This has unfortunately tended
to lead some owners to think that because no such action is required
the items either no longer exist or will last forever. This is certainly not
the case; it is essential to carry out regular visual examinations as
comprehensively as possible in order to spot any possible defects at
an early stage before they develop into major and expensive repairs.
For information applicable to later models, see Supplement.
Every 250 miles (400 km), weekly,
or before a long journey
m mCheck engine oil level
m mCheck brake reservoir fluid level
m mCheck tyre pressures
m mCheck operation of all lights and horn
m mTop up washer fluid reservoirs, adding a screen
wash, and check operation of washers and wipers
m mCheck coolant level
m mCheck battery electrolyte level
Every 6000 miles (10 000 km)
or six months, whichever comes first
m mRenew engine oil and filter (Chapter 1, Section 2)
m mCheck drivebelt tension (Chapter 2, Section 8)
m mCheck carburettor idle speed and mixture
adjustments (Chapter 3)
m mCheck contact points and dwell angle (mechanical
breaker distributors) (Chapter 4, Section 3)
m mCheck tyre tread wear (Chapter 7, Section 7)
m mCheck disc pads for wear (Chapter 8, Section 3)
Every 36 000 miles (60 000 km)
or three years, whichever comes first
m mRenew the timing belt - 1116 and 1299/1301 cc
(Chapter 1, Section 28)
m mCheck exhaust system for corrosion (Chapter 3,
Section 19)
m mRenew contact breaker points and adjust dwell
angle (mechanical breaker distributors) (Chapter 4,
Section 3)
m mCheck and adjust ignition timing (Chapter 4,
Section 4)
m mRenew spark plugs (Chapter 4, Section 11)
m mCheck clutch adjustment (Chapter 5, Section 2)
m mCheck transmission oil level (Chapter 6, Section 2)
m mCheck driveshaft and steering rack gaiters for splits
(Chapters 7 and 10)
m mCheck rear brake shoe linings for wear (Chapter 8,
Section 4)
m mCheck handbrake travel (Chapter 8, Section 16)
m mCheck headlamp beam alignment (Chapter 9,
Section 17)
m mCheck balljoints for wear (Chapter 10, Section 2)
m mCheck front wheel alignment (Chapter 10, Section 8)
m mCheck suspension bushes for wear (Chapter 11,
Section 2)
m mCheck seat belts for fraying (Chapter 12, Section 23)
m mLubricate controls, hinges and locks
Every 24 000 miles (40 000 km)
or two years, whichever comes first
m mRenew coolant anti-freeze mixture (Chapter 2,
Section 3)
m mRenew transmission oil (Chapter 6, Section 2)
m mRenew brake hydraulic fluid (Chapter 8, Section 12)
m mCheck for underbody corrosion and clean out door
and sill drain holes (Chapter 12, Section 2)
Every 12 000 miles (20 000 km) or
12 months, whichever comes first
m mCheck and adjust valve clearances (Chapter 1,
Sections 5 and 26)
m mRenew air cleaner element (Chapter 3, Section 2)

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

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

2 Engine oil and filter
1
1The engine oil level should be checked at
the weekly service (see “Routine
Maintenance”). Preferably check the level
cold, first thing in the morning or if the engine
has been running, allow at least ten minutes
to elapse after switching off to permit the oil to
drain.
2Withdraw the dipstick, wipe it clean on
non-fluffy material, re-insert it and then
withdraw it for the second time (photo).
3The oil level should be between the MIN
and MAX marks. If not, top up with specified
oil to the MAX mark. Pour the oil slowlythrough the filler orifice on the rocker cover.
To raise the oil level from MIN to MAX will
require approximately 1.1 litre (2.0 pints)
(photos).
4At the intervals specified in “Routine
Maintenance” the oil and filter should be
renewed.
5Have the engine at normal operating
temperature, remove the oil filler cap.
6Place a suitable container under the sump
pan. Unscrew and remove the oil drain plug
and allow the oil to drain (photo).
7While the oil is draining, unscrew and
discard the oil filter. To unscrew the filter, a
filter or chain wrench will normally be
required. If such a tool is not available, drive a
long screwdriver through the oil tester casing
and use it as a lever to unscrew the filter
cartridge.
8Smear the rubber sealing ring of the new oil
filter with oil and screw into position using
hand pressure only (photo).
9Refit the drain plug and refill the engine with
the correct quantity and grade of oil.
10Start the engine. It will take two or three
seconds for the oil warning lamp to go out.
This is normal and is due to the time taken for
the new filter to fill with oil.
11Switch off, check for leaks and check the
oil level, topping up if necessary.
3 Crankcase ventilation
system
1
1This system is designed to draw oil fumes
and blow-by gas (which has passed the piston
rings) from the crankcase and draw it into the
intake manifold when it will then be burned
during the normal combustion process.
2Regularly check the security of the system
hoses which run from the rocker cover or
crankcase breather unit (photo).
3Periodically, detach the hoses and clean
them out with paraffin and a brush or rag pull
through.
4Evidence of sludge or emulsified oil within
the hoses or inside the oil filler cap will
indicate that the engine is running too cool
particularly if the car is used mainly for short
journeys where the engine never reaches full
working temperature.
4 Major operations possible
without removing engine
from car
1The following work can be carried out without
the need to remove the engine from the car.
903 cc engine
Valve clearances - checking and adjusting
Timing chain and sprockets - removal and
refitting
1•8 Engine – general
3.2 Crankcase vent hose (1116 cc)Fig. 1.5 Sectional view of oil filter. Bypass
valve arrowed (Sec 2)2.8 Screwing on the oil filter (903 cc)
2.6 Engine sump drain plug
2.3B Topping up engine oil (1116 cc)2.3A Typical dipstick markings2.2 Withdrawing engine oil dipstick
(1116 cc)

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

3
System type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear mounted fuel tank, mechanically-operated fuel pump,
downdraught carburettor
Air cleaner element
903 cc (45) and 1116 cc (55) engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion W121
1116 cc (60) and 1299/1301 cc (70) engines . . . . . . . . . . . . . . . . . . . . . Champion W136
Fuel tank
Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.0 litre (9.25 gal)
Octane rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Leaded 97 RON minimum (see Supplement for use of unleaded petrol)
Fuel filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion L101
Carburettor - calibration (dimensions in mm)
Weber 32 ICEV 50/250/1
Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 903 cc engine
Venturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Auxiliary venturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5
Main jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.12
Air bleed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.70
Emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F89
Idle jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.47
Air idle jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.60
Pump jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.40
Pump outlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.40
Superfeed jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.80
Superfeed mixture jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.50
Fuel inlet needle valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.50
Anti-syphon device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.00
Idle mixture adjustment hole . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.50
Float setting (fuel level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.5 to 11.0
Float setting (travel/stroke) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45.0
Fast idle (throttle valve gap) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.75 to 0.80
Accelerator pump delivery (ten strokes) . . . . . . . . . . . . . . . . . . . . . . . . . 4.0 to 5.5 cc
Chapter 3 Fuel system
For modifications, and information applicable to later models, see Supplement at end of manual
Accelerator cable - adjustment and renewal . . . . . . . . . . . . . . . . . . 17
Air cleaner - servicing, removal and refitting . . . . . . . . . . . . . . . . . . . 2
Carburettor - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Carburettor idle speed and mixture - adjustment . . . . . . . . . . . . . . . 7
Carburettor (Solex C32 DISA 12) - servicing and adjustment . . . . . . 13
Carburettor (Solex C30 - 32 CIC/1) - servicing and adjustment . . . . 15
Carburettor (Solex C32 DISA 11) - servicing and adjustment . . . . . . 10
Carburettor (Weber 30/32 DMTR 90/250) - servicing and
adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Carburettor (Weber 32 ICEV 50/250/1) - servicing and adjustment . . 9
Carburettor (Weber 32 ICEV 51/250) - servicing and adjustment . . . 12Carburettors (Weber 32 ICEE/250 and Solex C32 DISA 14) -
description and adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Carburettors - general . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Choke control cable - removal and refitting . . . . . . . . . . . . . . . . . . . 18
Description and maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Economy meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Fault finding - fuel system . . . . . . . . . . . . . . . . . . . See end of Chapter
Fuel level transmitter - removal and refitting . . . . . . . . . . . . . . . . . . . 4
Fuel pump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Fuel tank - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Manifolds and exhaust system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3•1
Specifications Contents
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321

Engine idle speed
At normal operating temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 to 850 rev/min
CO percentage at idle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 maximum
Torque wrench settingsNm lbf ft
Exhaust manifold nuts (903 cc) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15
Exhaust and intake manifold nuts (1116 cc, 1301 cc) . . . . . . . . . . . . . . 28 20
Fuel pump nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 20
Carburettor mounting nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
3•4 Fuel system
2.11B Air cleaner mounting bracket and
pipe clip2.11A Air cleaner mounting studs (1116 cc)2.9 Crankcase vent hose at air cleaner
1 Description and
maintenance
1
1The fuel system consists of a rear-mounted
fuel tank, a mechanically-operated fuel pump
and a carburettor and air cleaner.
2On all engines except the 1301 cc a single
venturi downdraught carburettor is fitted. On
the 1301 cc version, a dual barrel carburettor
is fitted.
3Maintenance consists of periodically
checking the condition and security of the fuel
hoses to the pump and carburettor. The fuel
pump cannot be cleaned or repaired and in
the event of a fault developing, the pump
must be renewed.
4On ES versions, an electronic fuel cut-out
device is fitted which reduces fuel
consumption on overrun, see Chapter 9,
Section 33.
2 Air cleaner- servicing,
removal and refitting
1
1The air cleaner air intake draws air either
from the front of the car or from the outside of
the exhaust manifold according to ambient
temperature (photo).
2At an ambient temperature of 13ºC (55ºF)
and above, the SUN symbol should align with
the intake spout arrow head. Remove the
cover nuts and turn the cover.
3At an ambient temperature lower than this,
move the air cleaner cover until the
SNOWFLAKE symbol aligns with the intake
spout arrow head.
4At the intervals specified in “Routine
Maintenance” renew the air cleaner filter
element.
5To do this, remove the cover nuts and take
off the cover (photo).6Take out the filter element and discard it.
Wipe out the air cleaner casing (photo).
7Locate the new element and refit the cover
aligning the appropriate symbols.903 cc engine
8To remove the air cleaner from the 903 cc
engine, unscrew the nuts and take off the
cover. Lift out the filter element.
9Unbolt the air cleaner casing from the
carburettor flange and from the bracket on the
rocker cover. Disconnect the vent hose
(photo).
10Disconnect the warm and cool air intake
hoses from their collecting points and lift the
air cleaner from the engine.
1116 cc and 1301 cc engines
11Removing the air cleaner from the 1116 cc
engine is similar to that described for the
903 cc engine, but having a cylinder head
support bracket (photos).
2.6 Removing air cleaner element
2.5 Air cleaner cover2.1 Air cleaner hot air intake