Esp 500 FIAT 500 1958 1.G User Guide

FIG 10:9 Brake fluid reservoir
Key to Fig 1 0 : 9 1 Reservoir 2 Strainer 3 Cap, vented
PARKING BRAKE CONTROL CABLE AND SHEATH
.CABLE ADJUSTING NUTS
SHOE OPERATING LEVER
LEVER RETURN SPRING
FIG 10:10 Parking brake control and adjusting mech-
anism at lefthand side rear wheel
Inspect the surfaces of the plungers and the cylinder
bore. If there is any roughness, scoring or corrosion the
assembly should be renewed. Check that the reaction
spring and thrust washers are not corroded or distorted,
renewing any defective parts.
Reassembling wheel cylinders:
Clean the metal parts thoroughly and dry off any
solvent used. The rubber parts should be renewed auto-
matically when servicing the cylinder. Wet the internal
parts w i t h clean brake f l u i d and reassemble them in the
order shown in FIG 10 : 8 .
10810:7 Self-adjusting device
The new 500 Sedan is equipped with a specially
designed brake shoe clearance self-adjusting device
which eliminates all need for manual adjustment during
service.
Operation:
On either side face of the brake shoe rim are placed t w o
friction washers in line with an adjustment slot which is
machined into the brake shoe (see FIG 10:6). The
friction washers are held against the shoe by a pin and
bush screw together through the slot with a strong
spring in between. The hollow pin fits onto the stud in the
brake housing flange. A clearance of .0315 inch between
the pin hole and stud permits the necessary movement of
the shoes to ensure proper braking under normal
operating conditions. On later models the self-adjuster
assembly is held together by a circlip.
When the shoe clearance adjustment is no longer
correct, the braking action will overcome the resistance of
the friction washers and drag along the shoes into contact
with the drum. Once the brake pedal has been released,
the action of the return springs will be weaker than the
friction of the adjustment washers on the shoes and so
the shoes will remain in the new position taken up. As
further wear of the linings occurs the shoes will again
automatically be repositioned by the device.
Inspection and assembly:
During normal brake overhaul all the components of
the self-adjusting device should be thoroughly checked
and any parts badly worn or damaged must be renewed.
Before reassembly it is advisable to check the spring
rating using Fiat tester A.11493 by
compressing the
spring to a height of .374 inch which should give a
corresponding load reading of 97 ± 4.9 Ib. To re-
assemble the device after testing proceed as follows:
1 Place the pin of the self-adjusting device on support
A.54002/2 and insert first the friction washer followed
by the shoe, the second friction washer, the load spring
and the bushings.
2 Fit wrench A.54002/1 onto the support and by
exerting a slight pressure to overcome the spring load
fully tighten the bush onto the pin. Lock the pin and
bushing using a centre punch. Alternatively, fit the
circlip.
3 Install the shoes onto the brake housing flange and
hook up the t w o return springs. Move the shoes out-
wards as far as they will go and release them. Check
that during the return of the shoes the friction washers
have stayed in their new position.
10:8 Removing a flexible hose
Never try to release a flexible hose by turning the ends
w i t h a spanner. The correct procedure is as follows:
Unscrew the metal pipeline union nut from its con-
nection with the hose. Hold the adjacent hexagon on the
hose w i t h a spanner and remove the locknut which
secures the hose to the brackets. The hose can now be
turned without twisting the flexible part, by using a
spanner on the hexagon at the other end.
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CHAPTER 11
THE ELECTRICAL EQUIPMENT
11:1 Description
11:2 Battery
11:3 The generator
11:4 The starter
11:5 The control box
1 1 : 6 Fuses
1 1 : 7 Flasher unit
11:1 Description
All models covered by this manual have 12 volts
electrical systems in which the negative battery terminal
is earthed. There are three units in the regulator box to
control the charging circuit; a cut-out, a current regulator
and a voltage regulator. These are adjustable but it must
be stressed that accurate moving coil meters are required
when checking or altering the settings. Cheap and
unreliable instruments will make accurate adjustments
impossible.
There are wiring diagrams in Technical Data at the end
of this manual to enable those with electrical experience
to trace and correct wiring faults.
For t h e U.K. Market the headlamps are of the double
filament dipping renewable bulb type with adjustments
for individual beam settings.
The battery is located in the front compartment
forward of the petrol tank and the fuses to the rear o f the
petrol tank.
Detailed instructions for servicing the electrical equip-
ment will be found in this chapter, but it must be pointed
out that it is not sensible to try to repair that which is
seriously defective, electrically or mechanically. Such
equipment should be replaced by new units which can
be obtained on an exchange basis.
F500111
11 :8 Windscreen wipers
1 1 : 9 The lighting system
11:10 Panel and warning lights
11:11 The horn
11:12 Lighting and flasher switch
1 1 : 1 3 Fault diagnosis
11.2 The battery
This of the 12-volt lead/acid type and has to meet
heavy demands for current particularly in the winter. To
maintain the performance of the battery at its maximum
it is essential to carry out the following operations.
Keep the top of the battery and surrounding parts dry
and clean, as dampness can cause leakage between the
securing clamps and the battery terminals. Clean off any
corrosion from the metal parts of the battery mounting
with diluted ammonia and paint them with an anti-
sulphuric paint. If the terminal posts are corroded,
remove the cables and clean w i t h diluted ammonia.
Smear the posts w i t h petroleum jelly before remaking the
connections and fit the terminals securely. High electrical
resistance due to corrosion at the terminal posts is often
responsible for lack of sufficient current to operate the
starter motor.
Ensure t h a t the filler plugs are in good condition and
show no signs of cracks. This may cause leakage of
electrolyte and consequent corrosion. Test the condition
of the cells after topping-up the electrolyte level with
distilled water to just above the tops of the separators as
shown in FIG 11 :2 . Never add neat acid. If it is
necessary to make a new electrolyte due to loss by
spillage add sulphuric acid to the
distilled water.
It is highly dangerous to add water to acid.

Checking cut-out:
1 Closing voltage:
This test should be carried out at a temperature of
25°±10°C and the regulator should be connected to a
generator test bed as shown in FIG 11:7. The unit should
be operated under no load conditions for between 15 -
18 minutes with the cover installed and w i t h a voltage of
between 16.5 volts for an initial operating temperature of
15-20°C or 15 volts for an initial operating temperature
of 20-35°C. This will enable thermal stabilization of the
unit to be obtained so that the temperature of both the
cut-out shunt windings and the bymetallic springs
increase due to the heat developed by the windings and
reaches the normal operating setting.
Once thermal stabilization has been obtained the
generator should be restarted and the speed gradually
increased so that immediately the test lamp starts to
glow the voltmeter reading may be taken. This will be
the value of the cut-out contact closing voltage.
2 Reverse current:
This check should be carried out at a temperature range
of between 25°±10°C and it is recommended that it is
performed as soon as possible after the closing voltage
test so that the thermal stabilization remains unaltered.
Connect the regulator as shown in FIG 11:8 and
gradually speed up the generator to 4500 rev/min for
approximately 5 minutes. Ensure that the voltmeter reads
at least 14.5 volts and then gradually reduce the generator
speed carefully watching the movement of the ammeter
needle which should at first indicate a charging current
and then gradually move to zero and then to the other side
of the scale to indicate reverse current value. If the
generator speed is reduced further the reverse current
reading will increase to a given value and then suddenly
fall to zero which will indicate that the cut-out contact
has opened. This limit indicates the maximum reverse
current value which should not, under any circumstances,
exceed 16 amps.
During this test, to obtain the maximum reverse
current possible the reduction in generator speed must
not take more than 10 seconds otherwise the battery
voltage will drop excessively.
Checking voltage regulator:
This test should be carried out w i t h the regulator under
half load and at a temperature of 50°± 3°C. Connect the
regulator as shown in FIG 11:9 and operate the regulator
for approximately 30 minutes by supplying a current half
that of regulated current which is 1 6 ±5 amp. Once the
regulator has been brought to the required temperature
stop the generator and start it again, gradually increasing
the speed to a maximum of 4500 rev/min. Adjust the
rheostat for a generator output corresponding to half load
current of 8 ± 2 amps. When this generator output has
been set the voltage should be 14.2± .3 volts.
Checking current regulator:
Leave the regulator connected as shown in
FIG 11 :10
and this test must be carried out immediately after testing
the half load regulated voltage of the voltage regulator
when connected to a battery. Check that the ammeter
fitted will accommodate a 40 amp deflection: if not a
F500117
FIG 11 :9 Wiring diagram for checking the current and
voltage regulators
Key to Fig 11:9 GR Regulator GN 1.1 2.1 6 G Generator
FIAT D 90.12.16.3 V Voltmeter, 20 V scale (0.5% accuracy)
A Ammeter, 20 A scale (to check voltage regulator) and 40 A
scale (to check current regulator)
B Battery, 50 Ah, fully chargedR Rheostat, 25 A. 3
FIG 11 :10 Wiring diagram for setting the cut-out relay
Key to Fig 11 :10 B 2 V battery B 20 V batteryA Ammeter, 20 A scale ( 1 % accuracy) V Voltmeter, 20 V
scale (0.5% accuracy), directly connected to terminals 31—51
P Potentiometer for voltage adjustment, having such a capacity
that the current draw of the cut-out shunt winding does not
cause sensible variations in the voltage readings (voltmeter
under no load) S Test lamp, with 2 V, 3 W bulb, to signal
opening and closing of contacts R Rheostat, 4 12
AR Voltage drop resistor, suitable to allow turning on of A withT open and cut-out contacts open
Setting of instruments before inserting the unit: P At
minimum (voltmeter reads zero) T Open R All inserted
(max. resistance) T Open
FIG 11:11 Wiring diagram for setting the voltage and
current regulators
Key to Fig 11 :11 GR Regulator assembly GN 1.12.16
G Generator D 90.12.16.3 V Voltmeter, 20 V scale (0.5%
accuracy) A Ammeter, 20 Amp. scale (for voltage regulator),
or 40 Amp. scale (for current regulator) R Rheostat, 25
Amps., 3 Ohms B 50 Amp/h battery, fully charged I Switch

Checking cut-out:
1 Closing voltage:
This test should be carried out at a temperature of
25°±10°C and the regulator should be connected to a
generator test bed as shown in FIG 11:7. The unit should
be operated under no load conditions for between 15 -
18 minutes with the cover installed and w i t h a voltage of
between 16.5 volts for an initial operating temperature of
15-20°C or 15 volts for an initial operating temperature
of 20-35°C. This will enable thermal stabilization of the
unit to be obtained so that the temperature of both the
cut-out shunt windings and the bymetallic springs
increase due to the heat developed by the windings and
reaches the normal operating setting.
Once thermal stabilization has been obtained the
generator should be restarted and the speed gradually
increased so that immediately the test lamp starts to
glow the voltmeter reading may be taken. This will be
the value of the cut-out contact closing voltage.
2 Reverse current:
This check should be carried out at a temperature range
of between 25°±10°C and it is recommended that it is
performed as soon as possible after the closing voltage
test so that the thermal stabilization remains unaltered.
Connect the regulator as shown in FIG 11:8 and
gradually speed up the generator to 4500 rev/min for
approximately 5 minutes. Ensure that the voltmeter reads
at least 14.5 volts and then gradually reduce the generator
speed carefully watching the movement of the ammeter
needle which should at first indicate a charging current
and then gradually move to zero and then to the other side
of the scale to indicate reverse current value. If the
generator speed is reduced further the reverse current
reading will increase to a given value and then suddenly
fall to zero which will indicate that the cut-out contact
has opened. This limit indicates the maximum reverse
current value which should not, under any circumstances,
exceed 16 amps.
During this test, to obtain the maximum reverse
current possible the reduction in generator speed must
not take more than 10 seconds otherwise the battery
voltage will drop excessively.
Checking voltage regulator:
This test should be carried out w i t h the regulator under
half load and at a temperature of 50°± 3°C. Connect the
regulator as shown in FIG 11:9 and operate the regulator
for approximately 30 minutes by supplying a current half
that of regulated current which is 1 6 ±5 amp. Once the
regulator has been brought to the required temperature
stop the generator and start it again, gradually increasing
the speed to a maximum of 4500 rev/min. Adjust the
rheostat for a generator output corresponding to half load
current of 8 ± 2 amps. When this generator output has
been set the voltage should be 14.2± .3 volts.
Checking current regulator:
Leave the regulator connected as shown in
FIG 11 :10
and this test must be carried out immediately after testing
the half load regulated voltage of the voltage regulator
when connected to a battery. Check that the ammeter
fitted will accommodate a 40 amp deflection: if not a
F500117
FIG 11 :9 Wiring diagram for checking the current and
voltage regulators
Key to Fig 11:9 GR Regulator GN 1.1 2.1 6 G Generator
FIAT D 90.12.16.3 V Voltmeter, 20 V scale (0.5% accuracy)
A Ammeter, 20 A scale (to check voltage regulator) and 40 A
scale (to check current regulator)
B Battery, 50 Ah, fully chargedR Rheostat, 25 A. 3
FIG 11 :10 Wiring diagram for setting the cut-out relay
Key to Fig 11 :10 B 2 V battery B 20 V batteryA Ammeter, 20 A scale ( 1 % accuracy) V Voltmeter, 20 V
scale (0.5% accuracy), directly connected to terminals 31—51
P Potentiometer for voltage adjustment, having such a capacity
that the current draw of the cut-out shunt winding does not
cause sensible variations in the voltage readings (voltmeter
under no load) S Test lamp, with 2 V, 3 W bulb, to signal
opening and closing of contacts R Rheostat, 4 12
AR Voltage drop resistor, suitable to allow turning on of A withT open and cut-out contacts open
Setting of instruments before inserting the unit: P At
minimum (voltmeter reads zero) T Open R All inserted
(max. resistance) T Open
FIG 11:11 Wiring diagram for setting the voltage and
current regulators
Key to Fig 11 :11 GR Regulator assembly GN 1.12.16
G Generator D 90.12.16.3 V Voltmeter, 20 V scale (0.5%
accuracy) A Ammeter, 20 Amp. scale (for voltage regulator),
or 40 Amp. scale (for current regulator) R Rheostat, 25
Amps., 3 Ohms B 50 Amp/h battery, fully charged I Switch

FIG 11:12 Wiring diagram for setting the cutout relay
Key to Fig 11 :12 B 2 V battery B 20 V battery
A Ammeter, 15 A scale ( 1 % accuracy) V Voltmeter, 20 V
scale (0.5% accuracy), directly connected to terminals 31-51
P Potentiometer for voltage adjustment, having such a capacity
that the current draw of the cutout shunt winding does not cause
sensible variations in the voltage readings (voltmeter under no
load) S Test lamp, with 2 V, 3 W bulb, to signal opening
and closing of contacts R Rheostat, 4 , 1 2 A R Voltagedrop rheostat, suitable to allow turning on of S with T open and
cutout contacts open
Setting of instruments before inserting the unit: P At
minimum (Voltmeter reads zero) T Open R All inserted
(max. resistance) T Open
1
2
3
4
5
6
FIG 11:13 Location of electrical system fuses
Key to Fig 11 :13 1 Fuse N o . 30.2 2 Fuse N o . 30.3
3 Fuse N o . 56.b1 4 Fuse N o . 56.b2 5 Fuse N o . 15.54
6 Fuse N o . 30
meter w i t h a fuller scale deflection of 40 amp must be
substituted. Adjust the rheostat to give maximum
resistance and operate the regulator for approximately
30 minutes with regulator controlled current and 13 volt
supply. The resistor R of the rheostat should be adjusted
until the current is steady whilst the voltage drops. This
will indicate that the unit has reached normal operating
temperature. Stop the generator, restart it and speed up
gradually to 4500 rev/min. Check that the regulated
current value corresponds to the specified value of
1 6± .5 amps. By continually reducing the resistance the
current should remain constant. The voltage however
should decrease to as l o w as 12 volts.
118
Cut-out relay adjustment:
Ascertain the type of regulator fitted and then wire to
the test unit as shown in FIG 11:10 or FIG 11 :12.
Before the unit is assembled to the test bed the instru-
ments should be set as follows:
P - at minimum so that voltmeter reads zero.
T — open.
R - all inserted giving maximum resistance.
T - open.
1 Contact closing voltage:
This test should be carried out at an ambient tempera-
ture of 25°±10°C. Close the switch T and stabilize the
regulator thermally by feeding current into it for approxi-
mately 15 to 18 minutes at 16.5 volts which is obtained
by adjusting P for initial regulator operating temperatures
of between 15°-20°C or at 15 volts for initial operating
temperatures of 20°-35°C. Once the stabilizing of the
regulator has been completed bring the voltage to 12 6±
.2 volts by adjusting P. Adjust the load on the setting
spring by bending the relevant arm until the pilot light S
is extinguished. Reset P to m inimum and again increase
the voltage by P and check that the pilot lamp is extin-
guished at the specified voltage.
2 Reverse current:
This test must be carried out at a temperature of
25°± 10°C and it is recommended that it is carried out as
soon as possible after the closing voltage test so as to
maintain minimum regulator thermal stability. With the
switch T closed bring the voltage to 14.5 volts by
operating P. The contacts of the cut-out should be closed
and the pilot lamp S off. Close T and increase the reverse
current by means of the rheostat R and check that the
pilot lamp S glows as the contacts part. The opening may
also be unsteady which will be indicated by a slight
buzz from the unit. Check the value of the ammeter of the
reverse current causing the opening of the contacts and
this should not exceed 16 amps. If the reading is unstable
or S lights up at the recommended limit reset the reverse
current to the minimum value and repeat the test once
more. Finally open the switches T and T and again
adjust rheostat R and P to the minimum settings.
Voltage regulator adjustment:
This test should be carried out at a temperature of
5 0 ° ±3 ° C . Connect the unit as shown in FIG 11 :11 and
load the voltage regulator adjusting springs by bending
the relevant arm. With the unit at the required test
temperature close 1 start the generator and stabilize
the regulator thermally by feeding a current for 30
minutes at 15 volts, which is obtained by adjusting the
generator speed. The generator should then be stopped,
I opened and the generator restarted and gradually
speeded up to 4500 rev/min. The voltage regulator
spring load adjustment should be set by suitably bending
the relevant adjusting arm and by rheostat R so as to have
a voltage of 14.2±.3 volts and a half load current of
8 ± 2 amps. Finally check the steadiness and accuracy
of the voltage regulator setting by stopping the generator
and restarting after approximately 2 minutes and gradually
speeding up to 4500 rev/min.