1983 FIAT UNO coolant temperature

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

fluid. They are “sealed”. Liquid will get in, but
a thorough clean will be impracticable, and it
will be impossible to get new grease in.
17Check all the parts, get a new gland, two
new grommets, (1116 cc and 1301 cc) and a
new gasket. Scrape all deposits out of the
housing and off the impeller.
18To reassemble, start by inserting the new
grommets (1116 cc and 1301 cc) in the
grooves by each bearing. Fit the circlip to the
shaft, then the shouldered ring, bearings and
spacer. Fit the shaft and bearing assembly
into the cover. Fit the stop screw. Press on
the pulley.
19Fit the new gland (seal), seating it in its
location in the cover. Press the impeller onto
the shaft. The impeller must be put on part
way, and then the housing held in place to see
how far the impeller must go down the shaft
to give the correct clearance, which is 0.8 to
1.3 mm (0.03 to 0.05 in) as shown in Figs. 2.4
and 2.5.
20The impeller clearance can be checked
through the coolant passage in the side of the
pump.
21Refitting is a reversal of the removal
process, but use a new flange gasket and
tension the drivebelt as described in Section 8
(photo).
22Refill the cooling system.
10 Cooling system sensors
1A coolant temperature sender switch is
located in the cylinder head (above No. 1
spark plug) on 903 cc engines and adjacent to
No. 2 spark plug on 1116 cc and 1301 cc
engines.
2The switch operates the coolant
temperature gauge and an excessive
temperature warning lamp.
3On some models, a level sensor is screwed
into the side of the expansion tank. This
sensor consists of a pair of reed switches
within a capsule which are kept closed by the
strong magnetic flux generated by the
hydrostatic force inspired by the action of the
coolant against the float.
4If the coolant level drops then the magneticflux is weakened and the switches open.
5In the event of a fault developing, before
assuming that the cause is the sensor, check
all connecting wiring.
11 Heating and ventilation
system- description
1The heater is centrally mounted under the
facia and is of fresh air type.2Air is drawn in through the grille at the base
of the windscreen. It then passes through the
coolant heated matrix when it can then be
distributed through selective outlets
according to the setting of the control levers.
3A booster fan is provided for use when the
car is stationary or is travelling too slowly to
provide sufficient air ram effect.
4Fresh air outlets are provided at each end
and centrally on the facia panel.
12 Heater unit-
removal and refitting
1
1Drain the cooling system.
2Disconnect the heater hoses at the engine
compartment rear bulkhead.
3Working within the car under the facia
panel, disconnect the leads from the
heater blower by pulling the connecting plug
apart.
4If a radio is fitted, disconnect the
aerial, earth, speaker and power leads from
it.
Cooling and heating systems 2•5
Fig. 2.6 Checking impeller clearance
(Sec 9)9.21 Fitting coolant pump (1116 cc engine)
Fig. 2.7 Heater and ventilation system (Sec 11)
A Fresh air inlet flap
B Air distribution flap
C Coolant valveD Blower
E MatrixF Control levers
G Footwell air duct
2

7 Carburettor idle speed and
mixture- adjustment
4
1All carburettors have their mixture
adjustment set in production. The screw is
fitted with a tamperproof cap.
2Under normal circumstances, only the idle
speed screw need be adjusted to set the
engine idle speed to the specified level.
3Before attempting to adjust the idle speed
or mixture, it is important to have the ignition
and valve clearances correctly set and the
engine at normal operating temperature with
the air cleaner fitted.
4Where the mixture must be adjusted, prise
out the tamperproof plug and turn the mixture
screw in to weaken or out to enrich the
mixture until the engine runs smoothly without
any tendency to “hunt”.
5Ideally an exhaust gas analyser should be
used to make sure that the CO level is within
the specified range.
6Once the mixture has been correctly set,
re-adjust the idle speed screw.
8 Carburettor-
removal and refitting
2
1Remove the air cleaner.
2Disconnect the flow and return fuel hoses
from the carburettor and plug them.3Disconnect the coolant hoses from the
carburettor throttle valve plate block.
Provided the cooling system is cold and not
under pressure there should be almost no loss
of coolant. Tie the hoses up as high as
possible with a piece of wire.
4Disconnect the vacuum and vent hoses
from the carburettor.
5Disconnect the throttle and choke controls
from the carburettor.
6Unscrew the mounting flange nuts and lift
the carburettor from the intake manifold
(photo).
7Refitting is a reversal of removal. Use a new
flange gasket and make sure that the fuel
return hose is routed above the air cleaner
intake.
9 Carburettor
(Weber 32 ICEV 50/250/1)-
servicing and adjustment
4
1The carburettor top cover with float may be
removed without the need to withdraw the
carburettor from the manifold. The other
adjustments described will require removal of
the carburettor.
2Unscrew the filter plug from the top cover,
clean the filter screen and refit it.
3Extract the top cover fixing screws, lift the
cover and tilt it to unhook it from the
diaphragm capsule link rod.
4Access to the fuel inlet needle valve isobtained by carefully tapping out the float arm
pivot pin. Take care, the pivot pin pillars are
very brittle.
5Check that the needle valve body is tight
otherwise fuel can bypass the needle valve
and cause flooding.
Float adjustment
6Reassemble and check the float setting. Do
this by holding the top cover vertically so that
the float hangs down under its own weight.
Measure dimension (A) (Fig. 3.10) which
should be between 1 0.50 and 11.10 mm
(0.41 to 0.44 in) with the gasket in position. If
necessary, bend the float arm tab to adjust.
7Now check the float travel which should be
45.0 mm (1.77 in). If adjustment is required,
bend the end of the float arm.
Accelerator pump stroke
8Using a twist drill as a gauge, open the
throttle valve plate through 3.5 mm (0.138 in).
9Turn the nut on the accelerator pump rod
until it just makes contact with the pump
control lever.
Fast idle adjustment
10With the choke valve plate fully closed by
means of the control lever, the throttle valve
Fuel system 3•7
Fig. 3.9 Fuel return hose correctly located
(Sec 8)
8.6 Carburettor mounting flange nut8.2 Fuel hose at carburettor
Fig. 3.10 Float setting diagram (Weber 32 ICEV 50/250) (Sec 9)
A = 10.5 to 11.0 mm (0.41 to 0.44 in) B = 45.0 mm (1.77 in)Fig. 3.11 Accelerator pump setting diagram
(Weber 32 ICEV 50/250) (Sec 9)
X = 3.5 mm (0.138 in)
3

3The centralised door locking system can
operate independently of the key.
4To gain access to the lock solenoid and
linkage, remove the front door trim panel as
described in Chapter 12.
5Disconnect the battery negative lead.
6Disconnect the electrical wiring plugs from
the solenoid within the door cavity.
7Disconnect the solenoid from the lock lever
by removing the clip.
8Unscrew the two bolts which secure the
solenoid to the door and remove it.
9Renew the solenoid or switch as necessary.
10Refitting is a reversal of removal.
11Refer to Section 10 for details of system
fuses and relays.
33 Economy gauge
(Econometer)
2
1This device is fitted to ES (energy saving)
models and indicates to the driver the fuel
consumption (in litres per 100 km) coupled
with a needle which moves over coloured
sections of a dial to make the driver aware
that his method of driving is either conducive
to high or low fuel consumption. Refer to
Chapter 3, Section 16.
2The device is essentially a vacuum gauge
which also incorporates a warning lamp to
indicate to the driver when a change of gear is
required.
3A fuel cut-out valve (see Chapter 3, Sec-
tion 11) is used in conjunction with the
economy gauge so that when the accelerator
pedal is released during a pre-determined
engine speed range, fuel supply to the engine
is stopped, but resumes when the engine
speed falls below the specified range.
LED (light emitter diode)
4The gearchange indicator will only light up
at engine speeds in excess of 2000 rev/min
for vacuum pressures up to 600 mm Hg in 1st,
2nd and 3rd speed gears and for vacuum
pressures up to 676 mm Hg in 4th speedgear. The light will not come on if 5th speed
gear is engaged or if the coolant temperature
is below 55ºC.
5There is a two second delay in the light
coming on to prevent it operating during rapid
acceleration in a low gear.
6If the LED light comes on during
deceleration it should be ignored.
Fault finding
7A faulty economy gauge should be checked
in the following way.
8Refer to Section 21 and remove the
instrument panel.
9Disconnect the economy gauge L
connector and then connect a test lamp
between the BN cable contact and earth. If
the lamp comes on then the gauge supply
circuit is not open. If the lamp does not come
on, check all connections in the supply cable
which comes from the interconnecting unit of
the electrical system, also Fuse No 12.
10Now connect a voltmeter between the
white cable and earth. Check the voltage with
the engine not running, but the ignition
switched on. It should be between 0.7 and
0.9 volt. If the reading varies considerably
from that specified, check the connections
between the economy gauge and the fuel
cut-out device control unit. If the fault cannot
be rectified, renew the ignition control unit
(Digiplex system, see Chapter 4).
11Now check the closed throttle valve plate
switch by connecting a voltmeter between the
brown and BN cables of the L connector. With
the valve plate open, there should be no
reading, but with it open, voltage should be
indicated.
12Failure to conform as described will be
due to a faulty earth in the switch or a faulty
fuel cut-out device control unit.
13A further test of the throttle valve plate
switch may be carried out by disconnecting
the multi-plug from the fuel cut-out device
control unit.
14Connect a test lamp to contact 4 (positive
battery terminal). The lamp should come on,
when the engine is idling or the accelerator
released. If it does not, renew the throttle
valve plate switch.15Connect a tachometer to the brown/white
cable contact in the L connector and record
the engine speed with the engine running. If
no reading is obtained, renew the Digiplex
ignition control unit which must be faulty.
34 Check control (warning
module) system
2
1This is fitted into the instrument panel of
certain models to provide a means of
checking the operation of many electrical
circuits and other systems in the interest of
safety. Sensors are used where appropriate.
2The following components are not
monitored by the system, but have separate
warning lamps:
Handbrake “on”
Choke in use
Low engine oil pressure
Battery charge indicator
3The multi-functional electronic device
automatically checks the following functions
whether the engine is running or not:
Coolant level
Disc pad wear
Door closure
Engine oil level
Front parking lamps
Rear foglamps
Stop lamps
4The check information is stored by the
system monitor until the engine is started
when the display panel then indicates the
situation by means of the LEDs (light emitter
diodes) and the general lamp.
5If all functions are in order, the green panel
lamp will come on when the ignition key is
turned and will go out after two to three
seconds.
6If some functions are not in order, then the
red panel lamp will come on also the
appropriate LED.
Sensors - checking
7If a fault signal occurs which is
subsequently found to be incorrect, first
check the wiring connections between the
9•12 Electrical system
Fig. 9.15 Check system control panel (Sec 34)
A Parking lamps
B Coolant levelC Engine oil level
D Door closureE Brake fluid level
F Disc pad wearFig. 9.14 Location of control units (Sec 33)
A Digiplex ignition system control unit
B Fuel cut-out valve control unit

Cooling system................................................................................. 8
Part A: 999 cc engine
Description
Maintenance
Thermostat - removal and refitting
Coolant pump - removal and refitting
Part B: 1301 cc Turbo ie engine
Description
Part C: 1372 cc ie and 1372 cc Turbo ie engines
Description
Maintenance
Cooling system - draining, flushing and refilling
Radiator (and cooling fan) - removal and refitting
Thermostat - removal and refitting
Coolant pump - removal and refitting
Coolant pump/alternator drivebelt - checking, renewal and
tensioning
Part D: Heater unit later models
Heater unit - removal and refitting
Heater unit - dismantling and reassembly
Fuel and exhaust systems............................................................... 9
Part A: General
Unleaded fuel
Air cleaner modified types
Fuel pump (999 cc engine) - description, removal and
refitting
Fuel tank (999 cc engine)
Part B: Carburettor models
Carburettor (Weber 32 TLF) - description
Carburettor (Weber 32 TLF) - idle speed and mixture
Carburettor (Weber 32 TLF) - removal and refitting
Carburettor (Weber 32 TLF) - overhaul
Carburettor (Weber 30/32 DMTE) - general
Carburettor (Weber 30/32 DMTE) - overhaul
Carburettor (Weber 32 ICEV 61/250 and DMTE 30/32,
DMTE 30/150) - general
Carburettor (Solex C 30/32-CIC 8) - description
Part C: Bosch LE-2 Jetronic fuel injection system
Description
Maintenance
Fuel filter - renewal
Air cleaner element - renewal
Idle speed and mixture - adjustment
Fuel injection system - electrical tests
Fuel injection system - mechanical tests
Fuel injection system components - removal and
refitting
Throttle control linkage - general
Fuel tank - general
Part D: Bosch Mono-Jetronic fuel injection system
Description
Maintenance
Fuel filter - renewal
Air cleaner element - renewal
Idle speed and mixture adjustment
Accelerator control system - check and adjustment
Fuel system - depressurisation
Fuel pump and supply - system checks
Fuel pump - removal and refitting
Injector unit - removal and refitting
Intake air temperature sensor - removal and refitting
Fuel injector - removal and refitting
Electronic control unit (ECU) - removal and refitting
Inlet manifold - removal and refitting
Exhaust manifold - removal and refitting
Catalytic converter - general information
Fuel evaporation control system - generalPart E: Bosch L3.1/2 Jetronic fuel injection systems
Description
Fuel system - depressurisation
Maintenance
Fuel filter - renewal
Air cleaner element - renewal
Checks and adjustments
Injection system components - removal and refitting
Part G: Turbocharger system
Description
Precautions
Turbocharger (1301 cc ie engine) - removal and refitting
Turbocharger (1372 cc ie engine) - removal and refitting
Intercooler - removal and refitting
Injector cooling fan - removal and refitting
Fault finding - fuel injection system
Fault finding - turbocharger system
Ignition system................................................................................. 10
General
Ignition timing (all later models)
Breakerless ignition system - description
Distributor (breakerless type) - removal and refitting
Distributor (breakerless type) - overhaul
Breakerless ignition system components - testing
Microplex ignition system - description
Distributor (Microplex) - removal and refitting
Microplex ignition system components - testing
Digiplex 2 ignition system - description
Distributor (Digiplex 2) - removal and refitting
Spark plugs and HT leads - general
Fault finding - Microplex ignition system
Clutch................................................................................................ 11
Clutch pedal adjustment (cable clutch)
Hydraulic clutch - description
Maintenance (hydraulic clutch)
Clutch master cylinder - removal, overhaul and
refitting
Clutch operating cylinder - removal, overhaul and
refitting
Clutch hydraulic system - bleeding
Transmission.................................................................................... 12
Part A: 1301 cc Turbo ie engine
Description
Gearchange linkage - removal and refitting
Gearchange linkage (Antiskid models) - general
Final drive output shafts - description and oil seal
renewal
Part B: 1372 cc ie and 1372 cc Turbo ie engines
Description
Maintenance
Oil level - checking
Oil - renewal
Gearlever and linkages - general
Transmission - removal and refitting
Part C: 999 and 1108 cc with C514 type transmission
Description
Maintenance
Driveshafts........................................................................................ 13
Inboard joint boots (non-Turbo models, September 1987 on) -
modification
Intermediate driveshaft (Turbo ie models)
Inboard CV joints (Turbo ie models - overhaul
Right-hand driveshaft damper weight (1108 and 1372 cc
models) - removal and refitting
13•2 Supplement: Revisions and information on later models

Lubrication system
Oil pump type:
999/1108 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gear driven from front of crankshaft.
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pump operated from front of crankshaft. Oil pressure relief valve in
front cover.
Tooth tip-to-body clearance (999/1108 cc) . . . . . . . . . . . . . . . . . . . . . . 0.080 to 0.186 mm
Gear endfloat:
999/1108 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.025 to 0.056 mm
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.040 to 0.106 mm
Oil pressure (at normal operating temperature) . . . . . . . . . . . . . . . . . . . 3.4 to 4.9 bars
Oil filter:
999/1108 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion F107
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion C106
Torque wrench settingsNm lbf ft
Auxiliary shaft sprocket bolt (1372 cc) . . . . . . . . . . . . . . . . . . . . . . . . . . 83 62
Big-end cap bolts:
999/1108 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 30
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 38
Camshaft bearing cap bolts:
M8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 14
M6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7
Camshaft cover screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 6
Camshaft housing to lower cylinder head securing bolt (1372 cc) . . . . . 20 15
Camshaft housing to inlet manifold bracket bolt (1372 cc) . . . . . . . . . . 25 18
Camshaft sprocket bolt
999/1108 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 50
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 62
Centre mounting to final drive casing bracket (1201/1301 cc) . . . . . . . . 23 17
Coolant temperature switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Crankshaft pulley bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Crankshaft pulley nut (1372 cc) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 145
Crankshaft rear oil seal retainer bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7
Crankshaft sprocket bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 58
13•8 Supplement: Revisions and information on later models
View of front end from below on
the 1372 cc ie engine model
1 Oil filter
2 Engine oil drain plug
3 Starter motor
4 Horns
5 Transmission front mounting
6 Front fog lamp and adjuster
7 Driveshaft
8 Transmission rear mounting
9 Gearchange linkage
10 Exhaust downpipe and system
joint
11 Anti-roll bar
12 Track control arm
13 Tie-rod balljoint
14 Brake unit
15 Driveshaft damper
16 Underwing shield

Cooling system (continued)
Radiator fan cut-in temperature:
1301 cc Turbo ie:
1st speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 to 90ºC
2nd speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 to 94ºC
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 to 94ºC
Radiator fan switch-off temperature:
1301 cc Turbo ie:
1st speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 to 85ºC
2nd speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 to 89ºC
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 to 89ºC
Coolant pump/alternator drivebelt tension:
1372 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Approximately 10 mm deflection midway between crankshaft and
alternator pulleys under firm thumb pressure
Torque wrench settingsNm lbf ft
Coolant pump mounting bolts (999/1108 cc) . . . . . . . . . . . . . . . . . . . . . 8 6
Coolant pump to crankcase (1372 cc) . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Coolant temperature gauge sender unit (1372 cc ie) . . . . . . . . . . . . . . . 30 22
Coolant temperature sender unit (1372 cc) . . . . . . . . . . . . . . . . . . . . . . 27 20
Fan thermostatic switch (1372 cc) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 22
Thermal valve on inlet manifold (1372 cc):
M10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 15
M8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 7
Water pump cover (1372 cc) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 11
Fuel system
General
Air cleaner element
999 cc and 1108 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U520
1372 cc ie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U533
1301/1372 cc Turbo ie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion U522
Fuel filter:
999 cc and 1108 cc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion L101
1372 cc ie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion L201
1301/1372 cc Turbo ie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Champion L203
Carburettor calibration
Weber 32 ICEV 61/250 TLF 4/250
Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 903 cc 999 cc
Accelerator pump capacity (for 10 strokes) . . . . . . . . . . . . . . . . . . . . . . 3.8 to 6.3 cc -
Air bleed jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.80 mm 50/90
Air compensating jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 165
Air idle jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.60 mm -
Anti-flooding device (choke valve plate gap) . . . . . . . . . . . . . . . . . . . . . - 4.0 to 5.0 mm
Auxiliary venturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 mm -
Fast idle (throttle valve plate gap) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 0.65 to 0.75 mm
Float level (with gasket) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.75 mm 26.75 to 27.25 mm
Full power jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.50 mm 50
Emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F74 F70
Exhaust gas CO at idle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 to 2.0% 1.0 to 2.0%
Idle air bleed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 50/90
Idle jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.47 mm 47
Idle mixture adjustment port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.50 mm -
Idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 750 to 800 rpm 750 to 800 rpm
Main jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.10 mm 105
Needle valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.50 mm 1.5 mm
Pump jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.40 mm 35
Pump outlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.40 mm -
Venturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 mm 22 mm
Weber 32 TLF 4/252 (and 251) TLF 27/251
Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 999 cc 1108 cc
Accelerator pump capacity (for 10 strokes) . . . . . . . . . . . . . . . . . . . . . . 8 to 12 cc 8 to 12 cc
Air bleed jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.65 mm 1.65 mm
Air idle jet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.50 mm 0.50 mm
Auxiliary venturi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 mm 4.5 mm
Emulsion tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F70 F70
13•10 Supplement: Revisions and information on later models

depressurize the fuel system, before
disconnecting the fuel pipes and removing the
throttle body, as described in Section 9D.
34Disconnect the coolant and vacuum
hoses from the cylinder head and inlet
manifold (photo).
35Disconnect the electrical lead from the
coolant temperature switch, the LT leads from
the distributor and the idle cut-off solenoid
lead.
36Remove the distributor cap, disconnect
the plug leads and place the cap and leads to
one side of the engine compartment.
37Unbolt and remove the timing belt cover.
38Set No. 4 piston to TDC and then release
the timing belt tensioner and slip the belt from
the camshaft and coolant pump sprockets.
39Unbolt and remove the inlet manifold,
complete with carburettor, or throttle body as
applicable.
40Unbolt the exhaust manifold from the
cylinder head and tie it to one side of the
engine compartment; the downpipe bracket
will have to be disconnected.
41Unscrew the cylinder head bolts, a half
turn at a time in the reverse order to that
shown in Fig. 1.30 of Chapter 1. When the
bolts are free, remove them with their
washers.
42Lift the cylinder head from the block. If it is
stuck tight, insert pieces of wood into the
exhaust or inlet ports and use them as levers
to “rock” the head off the block. On no
account drive levers into the gasket joint orattempt to tap the head sideways as it is
located on positioning dowels.
43Remove and discard the cylinder head
gasket and both manifold gaskets.
44The cylinder head can be dismantled after
removing the camshaft and cam followers as
described in the preceding sub-Section.
45Further dismantling and decarbonising are
described in Chapter 1, Section 39. Note that
single valve springs are used.
46If the valves have been ground in, the
valve clearances will require adjusting, as
described previously. This should be done
before the cylinder head is refitted to the
engine.
47Before refitting the assembled cylinder
head, make sure that the head and block
mating surfaces are perfectly clean, and that
the block bolt holes have been cleared of any
oil.
48The camshaft sprocket timing mark must
be aligned with the one on the cylinder head.
49The new gasket should not be removed
from its nylon cover until required for use. Fit
the gasket dry to perfectly clean surfaces.
50Place the gasket on the cylinder block so
that the word ALTO can be read from above
(photos).
51Lower the cylinder head onto the block so
that it locates on the positioning dowels
(photo).
52The cylinder head bolts must have clean
threads, dipped in engine oil and allowed to
drain for thirty minutes. Screw the bolts infinger-tight and then tighten them in the
sequence shown in Fig. 1.30 of Chapter 1,
and in the stages specified (see Specification)
(photos).
53Refit the inlet manifold and carburettor
using a new gasket.
54Reconnect the exhaust manifold using a
new gasket. Tighten all nuts to the specified
torque. Reconnect the exhaust downpipe
bracket.
55Reconnect the timing belt and tension it
as described earlier.
56Refit the timing belt cover and the
distributor cap and camshaft cover.
57Reconnect all hoses, electrical leads and
controls.
58Fit the air cleaner.
59Fill and bleed the cooling system.
Supplement: Revisions and information on later models 13•23
5B.50A Cylinder head gasket5B.34 Inlet manifold coolant hose (A) and
brake servo vacuum hose (B)5B.32 Disconnecting the throttle cable
5B.52B Typical disc for angular tightening
of cylinder head bolts
5B.50B Cylinder head gasket top surface
marking
5B.52A Inserting a cylinder head bolt5B.51 Fitting the cylinder head
13