check engine FIAT 500 1957 1.G Owner's Manual
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Page 37 of 128
FIG 2:18Diagram of blow-by gases re-circulation device
Key to Fig 2:181 Head cover 2 Blow-by gases and oil vapours breather valve 3 Oil filler cap4 Strainer
9 Air suction pipe, air cleaner to carburetter 8 Flame trap
13 Exhaust duct 12 Crankcase 7 Carburetter 6 Air cleaner
11 Filter gauze
10 Movable partition 5 PipeEngine 110 F. 000 Engine 120.000
designed to dampen the air intake noise and the carburet-
ter venturi hiss and is so located in the blower conveyor
system so that only clean dry air is drawn into the induc-
tion system.
To ensure complete protection of the engine it is
recommended that the air filter element be replaced every
6000 miles or even earlier if the vehicle is operating in
dusty conditions.
It should be noted that an oversize air cleaner may be
obtained if the vehicle is to be operated in very dusty areas.
Air cleaner—engine 110 F.000:
To remove the air cleaner element, disengage both the
spring hooks 2 as shown in FIG 2:17 and lift away the
cover 4 by turning it inwards together with the hose 5. 2 : 9 Air cleaner (sedan)
The pleated paper air cleaner element is contained in a
casing housed in a recess of one of the silencing chambers
provided in the blower conveyor as shown in FIG 2:16.
The air cleaner is connected to the carburetter by means of
a specially shaped hose. The silencing chamber is
44For full instruction refer to Section 2 :6. Carburetter cleaning:See Section 2 :6 for full check details. Throttle valve components:
Engine 110 F. 000
Page 38 of 128
Air cleaner—station wagon:
A pleated paper air cleaner element is housed in a
special air intake chamber connected to the front of the
engine air cooling cowling (see FIG 4 : 2) . This chamber
will be seen located towards the rear of t h e power unit
compartment. Remove the retaining wing nut, lift off the
lid and the element can be withdrawn by lifting upwards.
2:10 Blow-by-gases recirculation device
Engine 110 F.000
All the oil vapours and blow-by-gases that are formed
in the engine crankcase are drawn to the cylinder head
cover recess 1 (see FIG 2:18). From here they travel into
the pipe 5 via a breather valve 2 which is firmly attached to
the oil filler cap 3 and the strainer 4 located in the filler
neck. The oil vapours and gases are then d r a w n back into
the duct 9 from the pipe 5 which connects the air cleaner
6 to the carburetter 7. This ensures a complete closed cir-
cuit circulation.
Engine 120.000:
From engine No. 288156 the oil vapours and blow-by-
gases instead of being exhausted to the atmosphere are
conveyed to the air cleaner and from here they are drawn
back into the combustion chambers. To ensure that an
excessive of oil vapour does not pass along the piping
with the blow-by-gases a diaphragm is fitted in the duct
in front of the breather valve 2 (see FIG 2 :18), the dia-
phragm comprising a filter gauze 11 and moveable parti-
tion 10.
It should be noted that the oil vapour strainer 4 (see
FIG 2:18) and the flame trap 8 can easily be removed
from their seating for cleaning or renewal.
2 : 1 1 Fuel tank
The fuel tank is located in the front compartment as
shown in FIG 2:19, it comprises a filler union fitted with a
cap, a fuel reserve supply indicator sender unit and a con-
nection incorporating a filter for the main fuel supply pipes.
To remove the tank proceed as follows:
1 Remove the contents of the front compartment includ-
ing the spare wheel and tool bag.
2 Disconnect the main fuel line at the sender unit and also
disconnect the cable to the fuel reserve supply indicator.
3 Remove the four screws together w i t h the clips that fix
the tank to the body and carefully lift away the fuel tank.
4 Carefully drain the contents of the tank into a clean dry
container of a suitable capacity.
Fuel tank—sedan (110 F.) and station wagon (120):
The fuel tank is arranged in the front compartment as
shown in FIG 2 :20. To remove the fuel tank proceed as
follows:
1 Remove both screws which secure the front ends of the
clamping bands to the dash panel. The screws are
shown by arrows in FIG 2 :20.
Petrol tank cleaning:
The tank must be thoroughly checked for leaks espe-
cially at the joint seams. Should a leak be found it is
F50045
advisable for a garage to attend to this as it is very dange-
rous to apply heat to a petrol tank without first taking strict
precautions and a garage will be in a better position to do
this. To clean the tank interior, remove the drain plug and
spray in a jet of air or petrol so that all sediment and dirt
deposits can be loosened. Then vigorously shake the tank.
Flush the tank w i t h petrol and blow the tank dry. Repeat
this procedure until the tank is clean. Refit the drain plug.
Whilst the petrol tank is away from the car it is advisable
to disconnect the fuel feed pipes at the pump and the
carburetter and ensure that these are clear by using an air
jet to one end of the pipe.
Key t o Fig 2 :20
Note Arrows point to fuel tank clamping band screws vent valve
indicator tank unit1 Fuel tank2 Filler cap with
3 Fuel suction pipe and reserve supply
4 Tank clamping bands
FIG 2:20 Location of the fuel tank in front compart-
ment, 500F, L FIG 2:19 Fuel tank in front compartment. The fuel
reserve supply indicator (red light) glows when fuel
amount in tank is less than .8 to 1.1 Imp galls, or 5 litre FUEL TANK
FUEL LINE TO PUMP
FUEL GAUGE CABLE
Page 41 of 128
FIG 3 : 1 Ignition system wiring diagram
BATTERY
SWITCHBREAKER COIL
SPARK PLUG
CONDENSER
FIG 3 : 2 Ignition distributor in place on engine with
cap lifted offCURRENT CONTACT
TO SPARK PLUG
BREAKER A R M
STATIONARY
CONTACT
CARRIER
ADJUSTING
SCREW
CONTACT POINTS HIGH TENSION)
CARBON CONTACT
3 : 3 Routine maintenance
Refer to FIG 3: 2 and remove the distributor cap and lift
off the rotor arm. Lubricate the cam spindle felt pad using
Fiat VS oil. There is provision for the oil to make its way
downwards. Squirt a few drops of oil into the distributor
shaft lubrication fitting, the location being shown in FIG
3:3 Smear a little grease on the cam and a small drop of
oil to the contact breaker point pivot.
Adjusting the contact breaker points:
Refer to FIG 3 : 2 and slacken the stationary contact
carrier adjusting screw. Slowly rotate the engine until one
one of the t w o cams has opened the points to the fullest
48
extent so that the gap is measured at the position of the
maximum opening. Reset the gap to a correct clearance of
.0185 to .0209 inch and tighten the contact carrier screw.
Cleaning the contact points:
If the contact points are dirty or pitted they must be
cleaned by polishing them with a fine carborundum stone
taking very great care to ensure that the contact faces are
flat and square. Afterwards wipe away all dust with a cloth
moistened in petrol. The contacts may be removed from
the distributor body to assist refacing and cleaning refer-
ring to Section 3:5. If the moving contact is removed
from its pivot, check that its operation is not sluggish. If it is
tight, polish the pivot pin with a strip of fine emery cloth,
clean off all dust and apply a tiny spot of oil to the top of
the pivot pin. If a spring testing gauge is available the
contact breaker spring should have a tension of 16.8± 1.8
oz. measured at the points.
3 :4 Ignition faults
If the engine runs unevenly set it to idle at a fast speed.
Taking care not to touch any metal part of the sparking
plug leads, pull up the insulator sleeve and short each
plug in turn, using a screwdriver with an insulated handle.
Connect the screwdriver blade between the plug top and
the cylinder head. Shorting a plug which is firing properly
will make the engine uneven running more pronounced.
Shorting a plug in a cylinder which is not firing will make
no difference.
Having located the
faulty cylinder, stop the engine and
remove the plug lead. Start the engine and hold the lead
carefully to avoid shocks so that the metal end is about
3/16 inch away from the cylinder head. A strong regular
spark shows that the fault might be with the sparking plug.
Remove and clean it according to the instructions in
Section 3 :8. Alternatively substitute it with a new plug.
If the spark is weak and irregular, check that the lead is
not perished or cracked. If it appears to be defective,
renew it and try another test. If there is no improvement,
remove the distributor cap and wipe the inside clean and
dry. Check the carbon brush located as shown in FIG 3 : 2 .
It should protrude from the cap moulding and be free to
move against the pressure of the internal spring. Examine
the surface inside the cap for signs of 'tracking' which can
be seen as a thin black line between the electrodes or to
some metal part in contact with the cap. This is caused by
sparking, and the only cure is to fit a new cap.
Testing the low-tension circuit:
Before carrying out electrical tests, confirm that the
contact breaker points are clean and correctly set, then
proceed as follows:
1 Disconnect the black low-tension cable from the
ignition coil and from the side of the distributor.
Connect a test lamp between the t w o terminals. Turn
the engine over slowly. If the lamp lights when the
contacts close and goes out when they open, the
low-tension circuit is in order. If the lamp fails to light
the contacts are dirty or there is a break or loose con-
nection in the low-tension wiring.
2 If the fault lies in the
low-tension circuit, switch on
the ignition and turn the crankshaft until the contact
breaker points are fully open. Refer to the wiring
diagram in Technical Data and check the circuit with
Page 43 of 128
FIG 3 : 4 Use of fixture Ap.5030/1 to check ignition
timing
Reassembly is the reverse procedure to dismantling but
the following points should be noted:
1 Lubricate the parts of the centrifugal advance mecha-
nism, the drive spindle and the part of the shaft which
accepts the cam w i t h Fiat VS oil.
2 Ensure that upon reassembly the slot in the rotor arm
housing matches the distributor driving dog. Lubricate
the felt pad in the rotor arm housing.
3 Fit the distributor back onto its support gently rotating
the rotor arm so that the drive dog engages w i t h the
drive shaft mating flange. Provided the crankshaft has
not been turned the rotor arm should finish up pointing
to No. 1 cylinder segment in the distributor cap. Tighten
the distributor retaining nut, refit the distributor cap and
leads to the spark plugs and the LT lead to distributor
body terminal.
4 Add a few drops of oil to the distributor shaft lubrication
fitting (see FIG 3:3).
3 : 6 Removing and dismantling distributor
(station wagon)
The distributor is located towards the top rear of t h e
engine and is bolted direct onto the crankcase rear cover as
shown in FIG 1 : 2 . It is driven direct by a gear in mesh w i t h
a corresponding gear on the camshaft. The basic design of
the distributor is the same as that for the sedan and sports
engine, except that the distributor cap has been redesigned,
there is a gear instead of the dog
drive and no distributor
support. To remove and dismantle the distributor proceed
as previously described taking great care about marking
the location of the distributor to rear cover and rotating
the engine until No. 1 cylinder is on compression. This will
ensure that reassembly is straightforward without loss of
ignition timing.
503:7 Timing the ignition
It is necessary to retime the ignition should the distribu-
tor shaft or camshaft have been removed. To retime the
ignition proceed as follows:
1 On the timing sprocket cover fit Fiat tool AP.5030/1 as
shown in FIG 3 : 4. Ensure No. 1 cylinder is on the
compression stroke with both valves closed. Rotate the
crankshaft until the mark on the centrifugal filter cover
lines up w i t h the 10° mark on the fixture. This setting
corresponds to a 10° static advance BTDC.
2 Check t h a t the points gap is correctly set between
.018 and .020 inch. Turn the distributor shaft until the
rotor points in the direction of No. 1 segment in the
cap and the points are just opening.
3 Without disturbing the distributor shaft, insert the lower
coupling on its toothed end, install the support and
tighten the locknut. Secure the distributor to the sup-
port using the mounting screw.
To check that the distributor is properly timed to the
engine and the centrifugal automatic advance is operating
correctly giving a
total advance of 18° to 28° respectively
proceed as follows:
1 Connect Fiat timing tester AP.5030 with a 220-volt-
single-phase power outlet fitted with a good earth
connection. It is important that the tester is earthed
before it is allowed to operate. Also ensure that the
tester earth terminal is connected to a bare metal part
of the vehicle.
2 Remove No. 1 spark plug lead, insert the strobe light
adapter and reconnect the spark plug lead. Using a
piece of white chalk mark the TDC position on the
centrifugal filter cover.
3 Start the engine and aim the strobe light beam towards
the chalk mark drawn on the centrifugal filter cover.
With the engine running slowly the mark on the centri-
fugal cover must correspond wi th the first white line
on the fixture (10°). Slowly increase the speed of the
engine so operating the automatic advance and the
chalk mark should move counterclockwise until at
maximum speed it reaches the second white mark on
the fixture.
It should be noted that the ignition timing for the model
500 sports engine the static advance is 10°, an automatic
advance of 12° giving a total advance at maximum engine
speed of 2 2 ° .
Should Fiat fixture AP.5030/1 not be available the
advance position may be set as follows:
1 Turn over the
engine until No. 1 piston is on the com-
pression stroke w i t h both valves closed.
2 Rotate the crankshaft clockwise until the reference
mark cast on the centrifugal filter cover is set .5118 to
.5512 inch ahead of the arrow cast on the timing
sprocket cover. This will give a static advance setting
of 10° BTDC.
3 Proceed as directed for ignition distributor timing and
mounting described earlier in this section.
3 : 8 Sparking plugs
The sparking plugs must be regularly inspected, cleaned
and the electrode gap adjusted to a gap of .019 to .023
inch.
The inspection of the deposits on the electrodes is par-
ticularly useful because the colour and type of deposit
Page 44 of 128
indicates the condition inside the combustion chamber
and may be used as a guide to engine tuning.
Before the spark plugs are removed b l o w away any
loose dirt from the plug recesses using a compressed air
jet or tyre pump. Store the plugs in the order of removal
ready for inspection.
Examine the gaskets and if they are about half their
thickness they may be used again otherwise they must be
replaced.
Inspect the electrode end of the plugs and note the
type and colour of the deposit. Normally it should be
powdery and range from b r o w n to a greyish tan in colour.
There will also be slight wear of the electrodes and the
general effect described is one which comes from mixed
periods of high-speed and low-speed driving. Cleaning
and resetting the gap is all that will be necessary.
If the deposits are white or yellowish they indicate long
periods of constant-speed driving or much low-speed
city driving. Again, the treatment is straightforward.
Dry, black, fluffy deposits are usually the result of
running with too rich a mixture. Incomplete combustion
of the petrol air charge may also be a cause and this might
be traced to a defect in the ignition system or excessive
idling.
Overheated sparking plugs have a white blistered look
about the centre electrode and the side electrode may be
badly eroded. This may be caused by poor cooling, wrong
ignition timing or sustained high speeds under heavy load.
To clean the sparking plugs effectively they should be
cleaned using an abrasive blasting machine and tested
under pressure once the electrodes have been reset. File
these until they are clean, bright and the faces parallel and
set the gap to .019 to .023 inch. Do not try to bend the
centre electrode.
Before replacing the plugs use a wire brush to clean the
threads taking care that the electrodes are not touched.
Thoroughly clean the spark plug in petrol, and dry using a
compressed air jet or a tyre pump. If difficulty is found in
screwing the plugs into the cylinder head by hand run a
tap d o w n the threads to clear away any carbon. If a tap is
not available use an old sparking plug with crosscuts d o w nthe threads. Finally tighten the plugs to a torque wrench
setting of 18 to 21 Ib ft.
Sparking plug leads:
The spark plug leads and the lead from the coil to the
distributor cap must be regularly checked for cracking of
the insulation and also correct seating in the distributor
cap and coil top. It is recommended that silicone grease is
smeared around the sockets before the leads are replaced
to ensure no moisture may enter causing difficult starting.
3 : 9 The distributor driving spindle (sedan and
sports engine)
If for any reason, the driving spindle has been removed
from its housing in the crankcase, it must be correctly
meshed w i t h the camshaft gear otherwise it
will be impos-
sible to set the ignition timing.
3:10 Fault diagnosis
(a) Engine w i l l not fire
1 Battery discharged
2 Distributor contact points dirty, pitted or maladjusted
3 Distributor cap dirty, cracked or tracking
4 Carbon brush inside distributor cap not touching rotor
5 Faulty cable or loose connection in low-tension circuit
6 Distributor rotor arm cracked
7 Faulty coil
8 Broken contact breaker spring
9 Contact points stuck open
(b) Engine misfires
1 Check 2, 3, 4, and 7 in (a)
2 Weak contact breaker spring
3 High-tension plug and coil leads cracked or perished
4 Sparking plug(s) loose
5 Sparking plug insulation cracked
6 Sparking plug gap incorrectly set
7 Ignition timing too far advanced
Page 49 of 128
OIL DRAIN PLUG COOLING AIR DUCTS
FIG 4 : 3 Oil sump with blower cowling. Arrows indicate
air outlets
BLOWER
SHAFT GENERATOR ARMATURE
VENT TUBE
FIG 4 : 4 Cooling blower mounted on generator shaft
extension
4 : 2 Air outlet thermostat and shutter
Refer to FIGS 4 :1 and 4 :2 where it will be seen that
the thermostat is located on the righthand side of the
engine cowling. The thermostat should start opening the
engine heated air outlet shutter when the temperature of
the air reaches between 158-165°F (178-185°F station
wagon) and the shutter should be in the wide open posi-
tion when the air has reached a temperature of between
178-189°F (196-207°F station wagon).
When the engine cooling air control system is being
inspected or serviced the following points should be
noted:
1 Check that when the shutter is in the closed
position the edge mates perfectly with the cowling
seating.
2 Ensure that the shutter can swivel freely.
3 Check that the initial thermostat movement is
between .0197 to .0394 inch.
4 Generally check the engine cowling for distortion, bad
jbint sealing or cracks.
56
Key to Fig 4 : 6 1 Circular seat i n cylinders 2 Head
ducts 3 Pierced screws
FIG 4 : 6 Diagram of the heating system safety device
(sedan and station wagon) FIG 4 : 5 Location of cooling air outlet thermostat and
shutter
ENGINE COWLING.
THERMOSTAT
LINK
AIR OUTLET SHUTTER
SHUTTER RETURN SPRING
4 : 3 Tension adjustment, thermostat to shutter
link:
The tension may be varied by using the shims which are
located between the upper shank of the thermostat and
the cover shoulder washer. Before any adjustment is made
ensure that the shutter is able to move freely and that the
return spring has not stretched or fractured. Refer to
FIG 4:5 which shows the location of the shutter and the
return spring.
Page 50 of 128
4 : 4 Heating system safety device
110F series sedan engines and later station wagon
engines incorporate a modification to the cylinder head
designed so that in the event of cylinder head gasket
failure exhaust gases are expelled outside the engine and
not leaked into the heating system.
The safety device comprises a square section circular
seat 1 (see FIG 4 :6) which is formed in the upper face of
the cylinder, a special duct in the cylinder head and a
pierced screw 3 for each cylinder.
The system is so designed that the exhaust gases are
released to the atmosphere from the circular seat in the
cylinder via the duct 2 and the pierced screw 3. It should
be noted that the screw 3 is also used for securing the
conveyor.
4 : 5 Maintenance
Due to the simple design of the air cooling system
maintenance has been kept to an absolute minimum and
should consist of the following checks:1 Inspect all the air conveyor system joints and ensure
that all the joint nuts and bolts are tight and that there
is no distortion between two joint faces.
2 Check that the tension of the generator and fan drive
belt is correct: with a hand pressure of approximately
22 Ib the belt should sag 13/32 inch. Adjust if necessary
as detailed in Chapter 1.
3 Ensure that the shutter can swivel freely and that the
spring is in a serviceable condition.
4 : 6 Fault diagnosis
(a) Engine overheating
1 Generator and fan drive belt slipping
2 Shutter control thermostat defective
3 Shutter unable to swivel freely
4 Shutter return spring broken
5 Leaking joints in conveyor system
F50057
Page 53 of 128
*Dimension to be obtained by
adjusting the throwout lever.
FIG 5:1 Clutch assembly longitudinal section (new
500, 500D sedan and early station wagon)
5 : 2 Removal and installation
To remove the clutch unit from the vehicle proceed as
follows:
1 Remove the engine (Chapter 1) or separate the gear-
box from the engine as described in Chapter 6.
2 Remove the six screws and washers that secure the
clutch cover to the flywheel and gently ease the cover
assembly from the location dowels in the flywheel and
lift away. This will also free the driven plate.
3 Carefully clean the driven plate and clutch cover using a
compressed air jet.
4 To refit the clutch cover assembly to the flywheel
ensure that the driven plate is assembled the correct
way round as shown in FIG 5 :1 and place the cover
onto the flywheel using the locating dowels.
5 To ensure that the driven plate is correctly centred use
Fiat pilot A.62023 (see FIG 5 : 5) or a suitably sized
mandrel. Tighten the clutch mounting screws diagonally
a turn at a time to ensure correct location of the cover
onto the flywheel face. Finally, tighten to a torque
wrench setting of 5.8 to 7.2 Ib ft.
5 :3 Dismantling and inspection of clutch cover
New 500, 500D sedan and early 500 station wagon :
To dismantle the clutch cover assembly proceed as
follows:
60
To assemble the clutch cover assembly proceed as
follows:
1 Place the pressure plate complete with carrier ring bolts
and springs on Fiat fixture 62038 (see FIG 5 : 2).
2 Fit the six pressure springs in their respective seats on
the pressure plate. Insert the cups on the springs and
replace the cover.
3 Compress the clutch cover, continually checking that
the withdrawal lever supporting bolts are properly
guided into their holes in the cover. Onto the bolts, fit
the three withdrawal levers w i t h their relevant nuts and
washers.
4 Replace the carrier ring on the levers and hook up the
retaining springs. 5 :4 Assembly and adjustment
N e w 500 sedan1 Place the clutch cover assembly on Fiat fixture A.62038
as shown in FIG 5 :6 and lock the cover using the three
T-handles provided.
2 Release the w i thdrawal lever carrier ring springs and lift
away the ring.
3 Unscrew the withdrawal lever fixing nuts on the bolts
and lift out the levers and washers. Gradually slacken
the three T-handles so relieving the pressure of the
clutch springs. Remove the clutch cover, springs and
lever mounting bolts. Carefully mark all the components
to ensure that they are assembled correctly so ensuring
that correct balance of the clutch unit is obtained.
Inspection:
Thoroughly clean all parts using a compressed air jet
and proceed as follows:
1 Thoroughly check the springs for signs of overheating
causing loss of tension and compare the effective length
of the springs which when fitted new should have a
length of .9646 inch under a load of not less than 43 Ib.
If the spring length is less t h a n t h e recommended
dimension fit a complete new set of springs.
2 The length of the withdrawal lever carrier ring retaining
springs should be checked which under a normal clutch
load should be .7677 inch whilst the length'of the
expanded spring under a load of 4.85 ± .44 Ib should
be 1.1811 inch. If the springs show sign of heating or
weakening a new set should be fitted.
3 Check the withdrawa l levers and their bolts for exces-
sive wear and fit new parts as necessary.
4 Inspect the pressure plate for an excessively ridged sur-
face or signs of cracking. If the ridges are not too severe
the face may be refaced by turning on a centre lathe.
Also inspect the flywheel friction surface which may
also be refaced providing that the ridges are not too
severe.
5 Whenever the clutch driven plate linings are worn a new
driven plate should be fitted.
6 Inspect the clutch shaft splines and these should not
have a lengthwise clearance in excess of .0039 inch and
side clearance of .0118 inch w i t h respect to the driven
plate hub. Ensure that the driven plate slides easily on
the clutch shaft protruding from the rear of the gearbox
differential unit as any plate drag may be the cause of
d i f f i c u l t y in gear selection.
Page 54 of 128
FIG 5:2 Clutch components (new 500, 500D sedan and early station wagon) DRIVEN PLATE
PRESSURE PLATE
LEVER CARRIER LEVER BOLTSBOLT NUTS PRESSURE SPRINGSWITHDRAWAL LEVERS CLUTCH COVER
LEVER CARRIER RING
SPRING
WASHER
FIG 5:3 Clutch assembly installed on engine (new
500, 500D sedan and early station wagon)
61
F500
To check the correct operation of the clutch cover 500 sedan (110.F) late 500 station wagon :
Inspection—diaphragm clutch: 5 Finally tighten down the cover assembly using the three
T-handles and adjust the clearance between the carrier
ring and its central shoulder by means of the three
adjustment nuts.setting the withdrawal levers stroke to
0039 inch. Check this adjustment using Fiat gauge
C.110 and when correct lock the adjustment nuts by
peining to the lever bolts.
500D sedan and early station wagon:
To assemble the clutch cover assembly proceed as
described above but adjust the withdrawal levers as
follows:
1 Secure the clutch cover assembly to Fiat fixture A.62038
with a ring .5413 to .5433 inch thick placed between
the clutch cover plate and the pressure plate.
2 Adjust the height of the three withdrawal levers so that
the lever tips are 1.9094 inch from the face of the Fiat
supporting plate.
Page 57 of 128
FIG 5:10 Clutch throw-out mechanism
Key to Fig 5:10 1 Clutch throw-out yoke
2 Yoke return spring 3 Rod nut and counternut
4 Adjustable rod 5 Clutch throw-out
onto this shaft the outer operating lever is attached by
means of a key.
A return spring connected to the outer operating lever
is anchored onto the gearbox casing. When the clutch is in
its normal position the spring keeps the central thrust
carbon ring away from the withdrawal levers carrier ring.
The carbon ring is pressed against the carrier ring by the
throw-out ring which is connected to the forked lever as
shown in FIG 5 : 8 .
The clutch pedal must have free travel of 1"3/8 to 1"9/16 inch.
Should any adjustment be necessary release the locknut
from the adjustable tie rod and adjust the position of the
tie rod until the correct adjustment is obtained. Tighten the
locknut.
500F. L and later station wagon:
The free travel of the clutch pedal should be 19/32 to
1"3/16 inch which corresponds to a clearance of .059 inch
between the throw-out sleeve and the ring (see FIG 5 : 7).
Should any correction be necessary release the adjust-
able rod locknut (see FIG 5:10), and reposition the
adjustable rod using the rod nut until the recommended
clutch pedal travel is obtained. Retighten the locknut.
5 : 8 Fault diagnosis
(a) Drag or spin
1 Oil or grease on driven plate lining
64
(g) Driven plate fracture
1 Check 2 and 3 in (a)
2 Drag and distortion due to hanging gearbox in plate hub (f) Tick or knock
1 Worn first motion shaft spigot or bearings
2 Badly worn splines in driven plate hub
3 Release plate out of line
4 Faulty Bendix drive on starter motor
5 Loose flywheel
(e) Rattle
1 Check 3 in (c)
2 Worn release mechanism
3 Excessive backlash in transmission
4 Wear in transmission bearings
5 Release bearing loose on fork (d) Judder
1 Check 1, 2 and 3 in (a)
2 Pressure plate not parallel with flywheel face
3 Contact area of driven plate linings not evenly distribu-
ted
4 Bent first-motion shaft
5 Buckled driven plate
6 Faulty power unit mountings
7 Worn suspension mountings
8 Weak rear springs
9 Loose drive shafts (c) Slip
1 Check 1, 2 and 3 in (a)
2 Check 2 in (b)
3 Weak pressure springs or diaphragm spring (b) Fierceness or snatch
1 Check 1, 2 and 3 in (a)
2 Worn clutch linings 2 Misalignment between engine and gearbox first motion
shaft
3 Driven plate hub binding on first motion shaft splines
4 Binding of first motion shaft spigot bearing
5 Distorted clutch plate
6 Warped or damaged pressure plate or clutch cover
7 Broken driven plate linings
8 Dirt or foreign matter in clutch