1966 FIAT 500 engine

switch contacts. The starter motor rotates driving the
engine through the pinion and ring gear. As soon as the
engine fires the starter hand lever must be released which
will open the starter switch contacts so stopping the
starter motor and the pinion will return under the action
of a spring to a neutral position.
Tests for a starter which does not operate:
Check the condition of the battery and particularly
the connections to the terminals and to earth. If the
battery is charged, switch on the lights and operate the
starter hand lever control. If the lights go dim but the
starter does not operate it shows that current is reaching
the starter motor. The probability is that the pinion of the
starter shaft is jammed in mesh due to dirty pinion splines
or a broken spring. To release the pinion engage a low
gear with the ignition switched off and rock the vehicle
backwards and forwards which should allow the pinion
to be disengaged from the flywheel ring gear. If it proves
impossible to free a jammed pinion the starter motor must
be removed for examination and repair.
If the lamps do not go dim, check the starter switch and
also check the connection between the battery and the
starter switch to ensure that they are tight and making
good electrical connection. If the starter motor still does
not work it should be removed from the power unit for
inspection.
Removing the starter:
To remove the starter motor from the power unit
proceed as follows:
1 Disconnect the positive terminal from the
battery post.
2 Release the hand lever control cable from the starter
motor engagement lever.
3 Disconnect the battery cable terminal from the starter
motor switch.
4 Remove the retaining nuts and washers holding the
starter motor to body to the transmission bellhousing
and gently ease backwards and lift away the starter
motor.
Examining the commutator and brush gear :
Refer to FIG 11:5 and remove the coverband 5. Hold
back each spring in turn and pull gently on the flexible
connection to the brush. If the brush does not move
freely remove it from its holder and polish the sides using
a fine file. Mark the brushes so that they will be replaced
in their original positions. If the brushes are so worn that
they no longer bear onto the commutator, or the brush
connector has become exposed on the running face, the
brushes must be renewed.
If the commutator is blackened it should be cleaned by
turning it against a petrol-moistened cloth. With the
brushes and commutator overhauled hold the body of the
starter motor in a vice and connect it with thick cables to a
12 volt battery. One cable should go to the starter
switch terminal and the other to the body of the starter.
The starter should run at high speed. If it does not, it
must be dismantled for further examination and testing.
F500115 Dismantling the starter:
To dismantle the starter proceed as follows:
1 Remove the coverband 5 (see FIG 11:5) and hold
back the brush springs and take out the brushes.
2 Remove the starter switch by releasing the t w o
mounting screws and lift away the switch.
3 Remove the commutator end head 16, slide off the
armature assembly from the drive unit and from the
pole shoes.
4 Release the engagement lever pin 6 and spring 7 from
the lever operating bracket on the drive end head. Lift
away the lever and withdraw the pinion assembly
complete which is shown in FIG 11:5.
Servicing the brushes
Test the brush springs with a balance, the correct
tension is 2.5 to 2.9 Ib. according to the wear of the
brushes. Fit a new spring if the tension is low.
The life of the brushes depends on the type of service
in which the vehicle is being used. In normal circum-
stances even when the starter is being used frequently,
the brushes should last more than 18,000 miles. If the
wear is found to be abnormal it will probably be found
that the commutator is either damaged or excessively
w o r n . Only Fiat replacement brushes must be used.
Testing the field coils:
Use a 12 volt bulb in one lead of a 12 volt battery.
Connect one lead to the brush connection joint to the coil
field and the other to the field coil current supply lead.
If the bulb does not light there is a break in the f i e l d coil
windings. This is not a complete test as it is still possible
for a coil to be earthed. Check this by moving the lead
from the brush connection and holding it on a clean
metal
surface on the yoke or body. If the bulb lights it shows
that the field coils are earthed.
The only sure way of curing faulty field coils is to take
the starter motor to a service station.
Examining the armature:
The armature shaft may be bent due to the starter
being operated whilst the engine is operating. Do not try
to straighten a bent shaft or machine the armature core to
obtain the correct clearance.
If the commutator is damaged or any wires or segments
have lifted from it, the assembly will have to be renewed.
Starter bearings:
Bearing bushes are of the porous bronzed type and
must not be reamed after fitting. Worn bearings should
be withdrawn by screwing a tap into them and pulling
on the tap. New bushes must be immersed in engine oil
for approximately twenty four hours before fitting. Press
them into place using a suitably sized drift which has a
spigot the length of the bearing and the diameter of the
starter shaft. When this is withdrawn after fitting, the
bore of the bush should be correct to size.
The pinion drive:
This unit is shown in FIG 11:5. The chief sources of
trouble are a dirty unit or a broken starting engagement

Lamp brilliance varies w i t h the speed of t h e car:
Check the condition of the battery. Examine the battery
connections. Make sure they are tight and renew faulty
cables.
11:10 Panel and warning lights:
All the gauges are clustered in a single instrument
mounted on the dashboard above the steering column.
Incorporated in this cluster is the parking light pilot light,
generator charge indicator, fuel reserve supply indicator,
low oil pressure indicator, and the speedometer w i t h
mileage recorder.
The parking lamp indicator glows green when the
ignition lock switch key is in either position 1 or 2 once
the toggle switch on the instrument panel has been
operated.
The generator charge indicator shows red only when
the ignition is turned on. It should be extinguished when
the generator output is sufficient for battery charge
(12.6 ± 0.2 volts) with the engine running at a speed
of 1100 rev/min and the headlights switched off.
The fuel reserve supply indicator shows red only when
the ignition is turned on and the amount of fuel in the
petrol tank has dropped to approximately .8 to 1.1
Imp. gallons.
The low oil pressure indicator shows red only when the
ignition is turned on and should be extinguished when
the oil pressure reaches 7.1 to 21.3 Ib/sq in, and opens
the sending unit contacts. Once the engine is at normal
operating temperature but at a speed below 1000 rev/
min the indicator might light up even the pressure is under
control and with normal operation.
All the bulbs fitted to the above described units are of
the tubular 2.5W type and to renew a bulb extract the
bulb holder from the rear of t h e instrument cluster and
release the bulb which is attached by a normal bayonet
coupling.
Fuel reserve supply indicator sender u n i t:
The fuel reserve supply indicator should be checked for
correct indication by allowing the fuel tank to empty and
then inserting .8 to 1.1 Imp. gallons at which stage the
light should extinguish. Any failure to do so should be
checked as follows:
1 Ensure that the indicator bulb operates correctly.
2 Check for complete circuit between the sender unit and
the indicator bulb.
3 If the sender unit float bracket is distorted the bulb
will
indicate a reserve supply of fuel greater or smaller than
specified. The bracket should be adjusted to give
correct indication of fuel level.
4 The sender unit could have been inadvertantly
damaged in which case the unit must be renewed.
11 :11 The horn
The horn circuit comprises the horn, push button at the
centre of the steering wheel and normal earth return
electrical circuit through the car body. One terminal is
connected to the battery whilst the other to the push
button on the steering wheel which when the button is
depressed the circuit will be closed so causing the horn
to operate.
F500
FIG 11 : 21 Number plate lamp
Key to Fig 11 : 21 A Lens and light cap mounting screws
B Lens
FIG 11 : 22 Horn (opened)
Key to Fig 11:22 1 Body 2 Diaphragm 3 Armature
4,5,6 Core 7 Cable: terminal-condenser-stationary contact
8 Cable: terminal-magnetizing coil end 9 Magnetizing coil
FIG 11 :23 Horn sound adjustment. Obtained by adjust-
ing the armature air gap
123

Before removing an apparently faulty horn check the
wiring and connections. Check that the mounting bolts
are tight and that the horn does not foul any adjacent part.
Removal and installation:
This is a straightforward operation and the only
precaution to be taken is to ensure that the rubber gasket
bonded to the horn body does not become detached. If
the horn is renewed, before installing the new horn bond
the rubber gasket to the new unit with adhesive in
the same position as was on the original horn unit fitted.
Should the horn fail to operate the following points
should be noted.
1 Damaged horn.
2 Broken connection between battery and horn.
3 Broken connection between horn and push button on
steering wheel
4 Damaged push button mechanism.
5 Directional signal and outer lighting changeover
switch blade contact failing to make contact with the
steering wheel hub ring contact.
6 Current lead displaced from the horn blade contact on
the directional signal and outer lighting switch.
7 Distorted or broken diaphragm in horn.
8 Connections or inner windings
broken or burnt.
9 Electro-magnet contact points dirty or excessively
worn.The contacts may be adjusted by the adjusting screw
after the points have been cleaned and refaced.
To adjust the tone of the horn use a ring spanner and
screwdriver as shown in FIG 11 :23.
It is recommended that if the horn unit operation is
unreliable a new unit should be fitted rather than the
original one repaired.
11:12 Lighting and flasher switch
Description:
The two switches provide a directional signal switch
which automatically returns to the rest position once a
turn has been negotiated and the steering wheel is
brought back to the straight-ahead position. The change
over switch controls the outer lights and the headlights
flasher. The complete unit is located under the steering
wheel on the steering column.
Switch unit removal:
1 Carefully pry off the horn push button at the steering
wheel centre using a fine blade screwdriver.
2 Disconnect the positive terminal of the battery.
3 Disconnect the plug in contact in the steering wheel
hub.
4 Unscrew the steering wheel retaining nut from the
inner column and remove the steering wheel from the
shaft.
5 Slacken the bolts securing the steering column support
to the body
6 Remove the plug in contacts from the switch unit
ensuring that their correct location is noted for re-
assembly.7 Remove the switch unit from the steering column.
124
Switch unit installation:
This is the reverse procedure to dismantling. It is
advisable after installation to check that the steering
wheel when in the straight-ahead position and the
directional signal switch lever in neutral, the reference
index on the outer face of the directional signal switch
drum is in line with the index on the steering wheel hub.
This will ensure correct sequence of operation.
11:13 Fault diagnosis
(a) Battery discharged
1 Lighting circuit shorted
2 Terminals loose or dirty
3 Generator not charging
4 Regulator or cut-out units not working properly
5 Battery internally defective
(b) Insufficient charging current
1 Loose or corroded battery terminals
2 Generator driving belt slipping
(c) Battery will not hold a charge
1 Low electrolyte level
2 Battery plates sulphated
3 Electrolyte leakage from cracked casing or top sealing
compound
4 Plate separators ineffective
(d) Battery overcharged
1 Voltage regulator needs adjusting
(e) Generator output low or nil
1 Belt broken or slipping
2 Regulator unit out of adjustment
3 Worn bearings, loose pole pieces
4 Commutator worn, burned or shorted
5 Armature shaft bent or worn
6 Insulation proud between commutator segments
7 Brushes sticking, springs weak or broken
8 Field coil wires shorted, broken or burned
( f ) Starter motor lacks power or will not operate
1 Battery discharged, loose cable connections
2 Starter pinion jammed in mesh with flywheel gear
3 Starter switch faulty
4 Brushes worn or sticking, heads detached or shorting
5 Commutator dirty or worn
6 Starter shaft bent
7 Engine abnormally stiff
(g) Starter motor inoperative
1 Check 1 in (f)
2 Armature or field coils faulty

CHAPTER 12
THE BODYWORK
12:1
12:2
12:3
12:4
12:5
12:6
12:7Bodywork finish
Interior and chrome cleaning
Door trim and accessories
Door handles and locks
Removing regulator and door glass
Removing windshield glass
Removing rear side windows12:8
12:9
12:10
12:11
12:12
12:13
12:14Removing rear window glass
Front compartment lid
Engine compartment lid
Folding top
Sun roof
Seats
Interior heater
12:1 Bodywork finish
Large scale repairs to body panels are best left to
expert panel beaters. Even small dents can be tricky, as too
much hammering will stretch the metal and make things
worse instead of better. Filling minor dents and scratches
is probably the best method of restoring the surface. The
touching up of paintwork is well within the powers of
most car owners, particularly as self-spraying cans of
paint in the correct colours are now readily available. It
must be remembered, however, that paint changes colour
w i t h age and it is better to spray a whole wing rather than
try to touch up a small area.
Before spraying it is essential to remove all traces of
wax polish with white spirit. More drastic treatment is
required if silicone polishes have been applied. Use a
primer surfacer or paste stopper according to the amount
of filling required, and when it is dry, rub it down with
400 grade Wet or Dry paper until the surface is smooth
and flush with the surrounding area. Spend time on
getting the best finish as this will control the final effect.
Apply the retouching paint, keeping it wet in the centre
and light and dry round the edges. After a few hours of
drying, use a cutting compound to remove the dry spray
and finish with liquid polish.
F500127
12:2 Interior and chrome cleaning
The cloth upholstery of the seating and the rear
compartment lining must be regularly cleaned to ensure
long life and preserve its attractive appearance. Any dust
or dirt that is blown into the car will settle on the uphol-
stery and will tend to wear the cloth causing an unsightly
appearance. It is recommended that the dust is wiped off
using either a vacuum cleaner or a stiff brush. To remove
ordinary soiling of the upholstery cloth proceed as
follows:
1 Using luke warm water and a neutral soap and a piece
of clean cloth wipe over the upholstery in the direction
of the nap.
2 Repeat the operation using a clean damp cloth and
warm water but no soap.
3 Allow the upholstery cloth to dry, use a stiff brush
against the direction of the upholstery nap to restore
its original fluffy look.
To obtain best results, any stains must be removed as
soon as possible otherwise as time passes they will
become more difficult, if not impossible to remove.
Certain stains require specific solvents and the instruc-
tions must be strictly adhered to.

SEAT RUBBER PAD
SEAT ARTICULATION SUPPORT
SEAT MECHANISM
CONTROL LEVER
SEAT SLIDING GUIDE
SEAT FIXED GUIDE
FIG 12:11 Sedan front seat
42
3
1
FIG 12:12 Sedan rear seat w i t h removable cushion
Key to Fig 12:12 1 Striker plate for triple acting door latch
2 Seat cushion 3 Dowels (two) for seat cushion location
4 Seat back
t h e rear v i e w mirror to the side of the dashboard.
5 Using a special compound sealing gun inject sealer
between weather strip outer lip and body.
12:7 Removing rear side windows
The rear quarter glass panes are located to the body
using the weather strips. To remove the glass simply push
outwards ensuring that a second operator is ready to
catch the glass as the weather strip becomes detached
from the body.
To reassemble the glass pane proceed as directed for
refitting the front windshield. Finally seal as previously
described using sealing compound.
12:8 Removing rear window glass
The rear window glass is removed and replaced in the
same manner as described in Section 12:6 for the
132
FIG 12:13 Centre catch of Sedan and Station Wagon
folding top. Dotted lines show the folding top control
handle in open position removal and replacement of the windshield glass.
Ensure t h a t the weather strip inner groove is thoroughly
filled using correct sealing compound.
1 2 : 9 Front compartment lid
The front compartment lid is hinged at the centre w i t h
the lower half of the hinge welded to the body upper
crossmember. The hinge upper half is secured to the
lower half by nuts and washers which are screwed onto
the lid studs. The compartment lid is kept closed by a
catch as shown in FIG 1 2 : 9 with an additional safety
hook to avoid accidental opening.
The catch release mechanism is controlled by a handle
which is located under the lefthand side of the instrument
panel and connected to the lock by means of a bowden
cable. The cable is arranged inside the front compartment
and the inner wire passes through a bracket and secured
to the catch. A return spring is fitted onto the catch, the
latter pivoting on a locked pin.
A specially shaped weather strip is arranged on the
front and side flange of the front compartment opening.
To refit and renew the weather strip ensure that all the old
bonding compound is removed using a stiff brush.
Spread fresh adhesive to the body shell and carefully
locate and press home the weather strip.
Six rubber bumpers are press fitted into the body shell
and at both ends of the front compartment lid to ensure
correct location and freedom of rattles.
12:10 Engine compartment lid
The opening and closing movement of the lid is con-
trolled by a locking handle. The lid opens downwards and
pivots on two lower hinges. The hinge pin is welded onto
the lid and its socket is welded to the body rear lower
crossmember. To remove the engine compartment lid
proceed as follows:
1 Remove the number plate lamp cable terminal.
2 Unhook the check strap by manipulating the retaining
cross piece.
3 Release the righthand pin self-locking nut and exert
a slight pressure on the righthand side of the lid so
pushing it towards the left.
Reassembly is the reverse procedure to dismantling.

12:11 Folding top
The f ol di n g top assembly comprises the following
items:
1 Imitation leather top w i t h vinylite back window.
2 Front end frame complete with two handles and
catches. A movable bow which slides on the frame
guide rails.
3 Three stiffening bows fixed by chrome plated buttons
and tipped with rubber blocks.
4 Front mouldings for t o p mounting on frame.
5 Rear moulding on top mounting engine cooling air
intake body panel.
6 Retaining strap for the roller stop.
The removal of the folding top is straightforward but
care should be taken on reassembly to the vehicle and the
following points should be noted:
1 The t o p rear moulding is secured by ten screws
consisting of six self-tapping screws and four standard
screws which are located as follows:
(a) One long self-tapping screw at each end.
(b) Two standard screws at centre.
(c) Two standard screws next to the long screws.
(d) Four self-tapping screws, two on each side
between the standard screws.
These screws also secure the upper end of the engine
air intake panel to body.
2 Having fixed the rear moulding spread the top across
t h e o p e n i n g . Ensure t h e pivoting bow is located
between the second and third stiffening bows. Using
special screws fix the frame rails to the upper inner
ends of the body side panels.
12:12 Sunroof
The 'new 500' sunroof model differs from the con-
vertible model in the arrangement of the top. The sunroof
comprises a rear metal panel and a front imitation leather
covering which acts as a collapsible top.
The weather strip surrounded back window is
located
on t h e rear metal panel and the following items are
cemented in place; plastic lining, foam rubber strip at
upper front end, and two rubber welts located on the
sides to prevent water ingress.
FIG 12:14 Folded top retaining strap
F500
133 FOLDED TOP STRAP
FOLDED TOP
FIG 12:15 Arrangement of rolled top. This should be
done carefully to prevent damaging the vinylite back
window. Roll must never obstruct engine air intake slots
FOLDING TOP LOCKING HANDLES
FIG 12:16 Sun Roof top in locked position
The rear metal panel is secured to the body shell by
means of four screws, four plain washers and four spring
washers and at the rear by means of nine self-tapping
screws which provide a mounting for the engine air
intake grill and gutter.
The collapsible top comprises the following items:
1 Imitation leather lining.
2 Metal frame with a front crossmember onto which the
control handles and top front latch strikers are fitted.
A movable bow riveted to the top lining and fitted with
rubber pads which rest on t h e t o p of t h e body.
3 Front moulding for the top lining mounting onto the
framing crossmember. FOLDED TOP STRAP

BOW
FIG 12:17 Sun Roof top in unlatched position
FIG 12:18 Diagrammatic view of car heating system
Key to Fig 12 :18 1 Thermostat controlling shutter 2 Shutter, engine cooling air outlet 3 Lever, heater hand control
4 Warm air outlet slots 5 Demister valve control knobs 6 Windshield demister diffusers
NOTE—The car may be also equipped, optionally, with a heating booster as shown in FIG 12:19
134
4 Rear moulding for the top lining mounting onto the
rear metal panel.
5 Top lining retaining strap which is secured to the front
end of t h e rear metal panel using a bridge bracket.
6 Bracket for strap which hooks up the top lining when
in the folded position.
Dismantling and reassembly is a straightforward
operation providing that careful note is made of the
location of all screws that are removed. To reassemble
it is suggested that the rear metal panel is mounted on
the body shell first. The collapsible top assembly is then
positioned and secured to the rear metal panel using eight
rivets. The top covering should be stretched to the closed
position and secured to both framing side arms to t h e
body shell wells using the special screws. 500F and L
models are similar, but with a single central sun roof latch:
t h e rear metal panel is no longer removable.
12:13 Seats
Front seats:
The front bucket seats comprise a one-piece tubular
frame covered with imitation leather or cloth padded

cushion and back rest. A number of rubber straps are
hooked across the frame under the cushion and in a
sheath covering on the seat back.
The bottom of the front seat frame ends are provided
with sliding guides which run in guide rails attached to
the floor. The sliding guides are pivoted on the frame
tubes to allow for forward tilting of the seats giving better
access to the rear compartment. Two rubber pads
provide cushioning of the seat frame on the guide rails
as shown in FIG 12:11. The control lever for seat
adjustment is fitted in the frame righthand tube to permit
unlocking of the seats so that they may be adjusted to
individual drivers requirements.
Rear seats (Sedan):
The rear seat comprises of a foam rubber cushion and
back. The seat back is cemented to the rear floor and
body shell bulkhead. The rear seat lining is of fabric and
imitation leather. The seat lining is held in place by four
self-tapping screws, t w o of which secure the floor below
the back window and two the lining at the base of t h e
back rest. Included with the seat assembly is a masonite
floor which is fitted below the rear window.
Rear Seat (Station Wagon):
The rear seat back rest is pivoted at the base of its
frame so that it can be folded down to form a load plat-
form surface. In the upright position it is retained in place
by t w o brackets mounted on either side of the body below
the side
windows.
12:14 Interior heater
Description:
Interior heating is accomplished by recirculation of
warm air from the engine cooling system through engine
cowling. Referring to FIG 12:18 a hose conveys warmed
air from the engine cowling to the centre tunnel floor
where warm air flows out through two slots being cut on
the windshield delivery hoses. Air admission can be
adjusted by turning the control lever to the right which
operates the tunnel throttle valve at the rear seat.
The heating system may be fitted with a booster which
comprises a casing on the front exhaust pipe being
connected to the engine cowling and the warmed air
passage tunnel. Warm air flowing to the car interior is
heated to higher temperature than that from the standard
version of heater (see FIG 12:19).
Windshield demisting:
As will be seen from FIG 12:18, t w o air hoses w i t h
throttle valves for airflow control are relayed from a casing
F500135
FIG 12:19 Diagram of booster
Key to Fig 12:19 1 Thermostat controlling shutter
2 Car interior heater booster 3 Hand control unit
in front of the centre of the floor tunnel. Flexible hoses
are connected to two air diffusers which are located on
the instrument panel and parallel to the windshield glass.
When the throttle valves 5 (see FIG 12:18) are operated
through the two control knobs, warmed air is directed
onto the windshield glass so preventing misting, frosting
or icing in adverse weather conditions.
Inspection:
Ensure that t h e lever, the lever spring and butterfly
valve hinge are not distorted. Check that the ducting to
the tunnel as well as the upper and lower hoses are air-
tight which if not, should be renewed.