air condition FORD SIERRA 1989 2.G Engine Electrical Systems Workshop Manual

Ignition timingLeaded petrolUnleaded petrol
(at idle with vacuum pipe disconnected)(4-star, 97 RON)(Premium, 95 RON)
Early “Economy” models (800 rpm - vacuum pipe connected) . . . . . . .16º BTDC12º BTDC
1.3 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12º BTDC8º BTDC*
1.6 litre models with VV carburettor . . . . . . . . . . . . . . . . . . . . . . . . . . . .12º BTDC8º BTDC*
1.6 litre models with 2V carburettor . . . . . . . . . . . . . . . . . . . . . . . . . . . .10º BTDC6º BTDC†
1.8 litre SOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10º BTDC6º BTDC†
1.8 litre CVH models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ESC Hybrid controlled, no adjustment possible
2.0 litre carburettor models up to 1985 . . . . . . . . . . . . . . . . . . . . . . . . .8º BTDC4º BTDC*
2.0 litre carburettor models from 1985 (except P100) . . . . . . . . . . . . . .10º BTDC6º BTDC†
P100 models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6º BTDC2º BTDC†
2.0 litre fuel injection models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12º BTDC8º BTDC†
*Fill with leaded petrol (4-star, 97 RON) every 4th tankful
†Not all vehicles are suitable for continuous operation on unleaded petrol.
Spark plugs
Make and type:
All models except 1.8 CVH, CVH (R6A), 2.0 DOHC and P100 . . . . . . . .Champion RF7YCC or RF7YC
1.8 CVH engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion RC7YCC or RC7YC
P100 model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion RF7YC or F7YC
1.6 and 1.8 CVH (R6A type) and 2.0 DOHC . . . . . . . . . . . . . . . . . . . . . .Champion RC7YCC
Electrode gap:
Champion F7YCC or RC7YCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.8 mm (0.032 in)
Champion RF7YC, F7YC or RC7YC . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.7 mm (0.028 in)
Note: The electrode gap above is the figure quoted by Champion for use with their recommended spark plugs. If plugs of any other type are fitted,
refer to their manufacturer’s gap recommendations.
HT leads
All SOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-09 or LS-10 boxed set
1.8 CVH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-10 boxed set
1.6 and 1.8 CVH (R6A type) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-30 boxed set
2.0 DOHC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Champion LS-29 boxed set
Maximum resistance per lead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30 000 ohms
Alternator
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Bosch, Lucas, Motorola, or Mitsubishi
Regulated output voltage at 4000 rpm (3 to 7 amp load) . . . . . . . . . . . .13.7 to 14.6 volts
Minimum brush length:
All alternator types except Motorola . . . . . . . . . . . . . . . . . . . . . . . . . .5.0 mm (0.20 in)
Motorola type alternators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.0 mm (0.16 in)
Starter motor
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Pre-engaged; Bosch, Cajavec, Lucas, or Nippondenso
Minimum brush length:
All except Bosch long frame 1.1 kW and JF, and Nippondenso . . . .8.0 mm (0.32 in)
Bosch long frame 1.1 kW and JF, Nippondenso starter motors . . . .10.0 mm (0.40 in)
Battery charge condition:
Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12.5 volts
Normal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12.6 volts
Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12.7 volts
Torque wrench settingsNmlbf ft
Spark plugs:
SOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 to 2815 to 21
CVH models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 to 3313 to 24
DOHC models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 to 2111 to 15
Crankshaft speed/position sensor clamp bolt (ESC Hybrid system) . . .4 to 73 to 5
Crankshaft speed/position sensor screw (DOHC) . . . . . . . . . . . . . . . . .3 to 52 to 4
Camshaft sprocket bolt (CVH models) . . . . . . . . . . . . . . . . . . . . . . . . . .95 to 11570 to 85
Air charge temperature sensor (CVH-R6A and DOHC) . . . . . . . . . . . . .20 to 2515 to 18
Engine coolant temperature sensor (CVH-R6A and DOHC) . . . . . . . . . .20 to 2515 to 18
Fuel temperature sensor (DOHC injection) . . . . . . . . . . . . . . . . . . . . . . .8 to 116 to 8
Alternator adjustment bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 to 2815 to 20
Alternator mounting bolts:
With coloured patch on threads . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41 to 5130 to 38
Without coloured patch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 to 2515 to 18
5•2Engine electrical systems

General information
The electrical system is of the 12 volt
negative earth type, and consists of a 12 volt
battery, alternator with integral voltage
regulator, starter motor and related electrical
accessories, components and wiring. The
battery is of the low maintenance or
maintenance-free “sealed for life” type and is
charged by an alternator which is belt-driven
from the crankshaft pulley. The starter motor
is of the pre-engaged type, incorporating an
integral solenoid. On starting the solenoid
moves the drive pinion into engagement with
the flywheel ring gear before the starter motor
is energised. Once the engine has started, a
one-way clutch prevents the motor armature
being driven by the engine until the pinion
disengages from the flywheel.
The ignition system is responsible for
igniting the air/fuel mixture in each cylinder at
the correct moment in relation to engine
speed and load. A number of different ignition
systems are fitted to models within the
Sierra/P100 range, ranging from a basic
breakerless electronic system to a fully
integrated engine management system
controlling ignition and fuel injection systems.
The ignition system is based on feeding low
tension voltage from the battery to the coil
where it is converted to high tension voltage.
The high tension voltage is powerful enough
to jump the spark plug gap in the cylinders
many times a second under high compression
pressures, providing that the system is in
good condition. The low tension (or primary)
circuit consists of the battery, the lead to the
ignition switch, the lead from the ignition
switch to the low tension coil windings
(terminal + /15) and also to the supply terminal
on the electronic module, and the lead from
the low tension coil windings (terminal -/1) to
the control terminal on the electronic module.
The high tension (or secondary) circuit
consists of the high tension coil windings, the
HT (high tension) lead from the coil to the
distributor cap, the rotor arm, the HT leads to
the spark plugs, and the spark plugs.
The system functions in the following
manner. Current flowing through the low
tension coil windings produces a magnetic
field around the high tension windings. As the
engine rotates, a sensor produces an
electrical impulse which is amplified in the
electronic module and used to switch off the
low tension circuit.
The subsequent collapse of the magnetic
field over the high tension windings produces
high tension voltage which is then fed to the
relevant spark plug via the distributor cap and
rotor arm. The low tension circuit is
automatically switched on again by the
electronic module, to allow the magnetic field
to build up again before the firing of the next
spark plug. The ignition is advanced and
retarded automatically to ensure that thespark occurs at the correct instant in relation
to the engine speed and load.
To improve driveability during warm-up
conditions and to reduce exhaust emission
levels, a vacuum-operated,
temperature-sensitive spark control system is
fitted to certain vehicles.Inductive discharge system
This is the least sophisticated system fitted
to the Sierra/P100 range, and comprises a
breakerless distributor and an electronic
switching/amplifier module in addition to the
coil and spark plugs.
The electrical impulse which is required to
switch off the low tension circuit is generated
by a magnetic trigger coil in the distributor. A
trigger wheel rotates within a magnetic stator,
the magnetic field being provided by a
permanent magnet. The magnetic field across
the two poles (stator arm and trigger wheel) is
dependent on the air gap between the two
poles. When the air gap is at its minimum, the
trigger wheel arm is directly opposite the
stator arm, and this is the trigger point. As the
magnetic flux between the stator arm and
trigger wheel varies, a voltage is induced in
the trigger coil mounted below the trigger
wheel, and this voltage is sensed and then
amplified by the electronic module and used
to switch off the low tension circuit. There is
one trigger wheel arm and one stator arm for
each cylinder (4).
The ignition advance is a function of the
distributor and is controlled both mechanically
and by a vacuum operated system. The
mechanical governor mechanism consists of
two weights which move out from the
distributor shaft as the engine speed rises due
to centrifugal force. As they move outwards,
they rotate the trigger wheel relative to the
distributor shaft and so advance the spark.
The weights are held in position by two light
springs and it is the tension of the springs
which is largely responsible for correct spark
advancement.
The vacuum control consists of a
diaphragm, one side of which is connected
via a small bore hose to the carburettor or
inlet manifold and the other side to the
distributor. Depression in the inlet manifold
and/or carburettor, which varies with engine
speed and throttle position, causes the
diaphragm to move, so moving the baseplate
and advancing or retarding the spark. A fine
degree of control is achieved by a spring in
the diaphragm assembly.
ESC (Electronic Spark Control) system
This system is only fitted to early
“Economy” models, and comprises a “Hall
effect” distributor, and an ESC module, in
addition to the coil and spark plugs.
The electrical impulse which is required to
switch off the low tension circuit is generated
by a sensor in the distributor. A trigger vane
rotates in the gap between a permanent
magnet and the sensor. The trigger vane has
four cut-outs, one for each cylinder. When
one of the trigger vane cut-outs is in line with
the sensor, magnetic flux can pass betweenthe magnet and the sensor. When a trigger
vane segment is in line with the sensor, the
magnetic flux is diverted through the trigger
vane away from the sensor. The sensor
senses the change in magnetic flux and sends
an impulse to the ESC module, which
switches off the low tension circuit.
The ignition advance is a function of the
ESC module and is controlled by vacuum. The
module is connected to the inlet manifold by a
vacuum pipe, and a transducer in the module
translates the vacuum signal into electrical
voltage. From the vacuum signal, the ESC
module determines engine load, and engine
speed is determined from the interval
between impulses supplied by the distributor
sensor. The module has a range of spark
advance settings stored in its memory, and a
suitable setting is selected for the relevant
engine speed and load. The degree of
advance can thus be constantly varied to suit
the prevailing engine speed and load
conditions.
ESC II (Electronic Spark Control II)
system
1.8 and 2.0 litre SOHC carburettor models
This system is a development of the ESC
system described previously in this Section,
but it enables more accurate control of engine
operation due to the inclusion of additional
monitoring features and control outputs.
Vehicles fitted with the ESC II system have an
electric inlet manifold heater which warms the
air/fuel mixture when the engine is cold, thus
reducing the amount of fuel enrichment
required, lowering fuel consumption and
improving driveability when the engine is cold.
The heater is operated by the ESC II module
receiving information on the engine temperature
from an engine coolant temperature sensor
mounted in the inlet manifold.
On 2.0 litre SOHC models, the ESC II
module operates a carburettor stepper motor
to control the engine idle speed. Using
information on engine speed, load,
temperature and throttle position (supplied by
a switch on the carburettor), the module
operates the stepper motor to maintain a
constant idle speed. On models equipped
with automatic transmission and/or air
conditioning, additional inputs are supplied to
the module to allow it to operate the stepper
motor to compensate for the additional engine
load imposed by the automatic
transmission/air conditioning. The ESC II
module also operates a “power hold” relay
which allows the stepper motor to function
briefly after the ignition has been switched off
in order to perform an anti-run-on and
manifold ventilation cycle.
2.0 litre DOHC carburettor models
A development of the ESC II system is used
to control the operation of the engine. The
module receives information from a
crankshaft speed/position sensor (similar to
that described for the ESC Hybrid system),
except that the sensor is activated by a
toothed disc on the rear of the crankshaft,
inside the cylinder block), and an engine
coolant temperature sensor.
1General information and
precautions
Engine electrical systems 5•3
5

The ignition advance is a function of the
ESC II module, and is controlled by vacuum.
The module is connected to the carburettor
by a vacuum pipe, and a transducer in the
module translates the vacuum signal into an
electrical voltage. From the vacuum signal,
the module determines engine load; engine
speed and temperature are determined from
the crankshaft speed/position sensor and the
engine coolant temperature sensor. The
module has a range of spark advance settings
stored in its memory, and a suitable setting is
selected for the relevant engine speed, load
and temperature. The degree of advance can
thus be constantly varied to suit the prevailing
engine speed and load conditions.
ESC Hybrid (Electronic Spark Control
Hybrid) system
This system is fitted to 1.8 CVH models,
and comprises various sensors and an ESC
Hybrid module, in addition to the coil and
spark plugs. The distributor serves purely to
distribute the HT voltage to the spark plugs
and consists simply of a rotor arm mounted
directly on the end of the camshaft, and a
distributor cap.
The electrical impulse which is required to
switch off the low tension circuit is generated
by a crankshaft speed/position sensor which
is activated by a toothed wheel on the
crankshaft. The toothed wheel has 35 equally
spaced teeth with a gap in the 36th position.
The gap is used by the sensor to determine
the crankshaft position relative to TDC (top
dead centre) of No 1 piston.
Engine load information is supplied to the
ESC Hybrid module by a vacuum transducer
within the module which is connected to the
inlet manifold by a vacuum pipe. Additional
inputs are supplied by an inlet
manifold-mounted engine coolant temperature
sensor, and an air charge temperature sensor
mounted in the base of the air cleaner. The
module selects the optimum ignition advance
setting based on the information received from
the various sensors. The degree of advance
can thus be constantly varied to suit the
prevailing engine conditions.
In addition to the ignition circuit, the module
also controls an electric choke heater, and a
solenoid valve which in turn controls a throttle
damper on the carburettor. The electric choke
heater is operated by the module using
information supplied by the engine coolant
temperature sensor. The heater is used to
slow down the rate at which the choke comes
off, thereby improving driveability and overall
fuel consumption when the engine is cold. The
solenoid valve controls the vacuum supply to
the carburettor throttle damper. The throttle
damper prevents sudden closing of the throttle
during deceleration, thus maintaining
combustion of the air/fuel mixture which
reduces harmful exhaust gas emissions.
Note that there is no provision for
adjustment of ignition timing with the ESC
Hybrid system.
EEC IV (Electronic Engine Control IV)
system
2.0 litre SOHC fuel injection models
This system controls both the ignition and
fuel injection systems. The EEC IV module
receives information from a “Hall effect”
distributor sensor (similar to that described
previously in this Section for the ESC system),
an engine coolant temperature sensor
mounted in the inlet manifold, a throttle
position sensor, and an air flow meter.
Additionally, on models equipped with
automatic transmission and/or air
conditioning, additional inputs are supplied to
the module to allow it to raise the idle speed
to compensate for the additional engine load
imposed by the automatic transmission/air
conditioning. The module provides outputs to
control the fuel pump, fuel injectors, idle
speed, and ignition circuit. Using the inputs
from the various sensors, the EEC IV module
computes the optimum ignition advance, and
fuel injector pulse duration to suit the
prevailing engine conditions. This system
gives very accurate control of the engine
under all conditions, improving fuel
consumption and driveability, and reducing
exhaust gas emissions. A “limited operation
strategy” (LOS) means that the vehicle is still
driveable, albeit at reduced power and
efficiency, in the event of a failure in the
module or its sensors.
2.0 litre DOHC fuel injection models
A development of the EEC IV system is
used to control both the ignition and fuel
injection systems. The module receives
information from a crankshaft speed/position
sensor (similar to that described for the ESC
Hybrid system), except that the sensor is
activated by a toothed disc on the rear of the
crankshaft, inside the cylinder block), a
throttle position sensor, an engine coolant
temperature sensor, a fuel temperature
sensor, an air charge temperature sensor, a
manifold absolute pressure (MAP) sensor, and
a vehicle speed sensor (mounted on the
gearbox). Additionally, on models with a
catalytic converter, an additional input is
supplied to the EEC IV module from an
exhaust gas oxygen (HEGO) sensor. On
models with automatic transmission,
additional sensors are fitted to the
transmission, to inform the EEC IV module
when the transmission is in neutral, and when
the kickdown is being operated.
The module provides outputs to control the
fuel pump, fuel injectors, idle speed, ignition
system and automatic transmission.
Additionally, on models with air conditioning,
the EEC IV module disengages the air
conditioning compressor clutch when starting
the engine, and when the engine is suddenly
accelerated. On models fitted with a catalytic
converter, the EEC IV module also controls
the carbon canister-purge solenoid valve.
Using the inputs from the various sensors,
the EEC IV module computes the optimum
ignition advance, and fuel injector pulse
duration to suit the prevailing engine
conditions. A “limited operation strategy” (LOS)means that the vehicle is still driveable, albeit at
reduced power and efficiency, in the event of a
failure in the module or one of its sensors.
1.6 litre and 1.8 litre (R6A type) CVH models
A development of the EEC IV system is
used to control both the ignition and fuel
injection systems. A fully electronic
Distributorless Ignition System (DIS) is fitted,
replacing the mechanical distribution of high
tension voltage (by a rotating distributor) with
“static” solid-state electronic components.
The system selects the most appropriate
ignition advance setting for the prevailing
engine operating conditions from a three-
dimensional map of values stored in the EEC
IV control module memory. The module
selects the appropriate advance value
according to information supplied on engine
load, speed, and operating temperature from
various sensors.
The EEC IV module receives information
from a crankshaft speed/position sensor
(similar to that described for the ESC Hybrid
system), except that on 1.6 litre engines, the
sensor is activated by a toothed disc on the
flywheel), a throttle position sensor, an engine
coolant temperature sensor, an air charge
temperature sensor, a manifold absolute
pressure (MAP) sensor, a vehicle speed
sensor (mounted on the gearbox), and an
exhaust gas oxygen sensor.
The module provides outputs to control the
fuel pump, fuel injector, throttle valve control
motor, pulse-air control solenoid, carbon
canister purge solenoid (where applicable),
and the ignition system.
Using the inputs from the various sensors,
the EEC IV module computes the optimum
ignition advance and fuel injector pulse dura-
tion to suit the prevailing engine conditions. A
“limited operation strategy” (LOS) means that
the vehicle will still be driveable, albeit at
reduced power and efficiency, in the event of
a failure in the module or one of its sensors.
Precautions
General
It is necessary to take extra care when
working on the electrical system to avoid
damage to semi-conductor devices (diodes
and transistors), and to avoid the risk of
personal injury. In addition to the precautions
given in the “Safety first!” Section at the
beginning of this manual, take note of the
following points when working on the system.
Always remove rings, watches, etc before
working on the electrical system. Even with
the battery disconnected, capacitive
discharge could occur if a component live
terminal is earthed through a metal object.
This could cause a shock or nasty burn.
Do not reverse the battery connections.
Components such as the alternator or any
other having semi-conductor circuitry could
be irreparably damaged.
If the engine is being started using jump
leads and a slave battery, connect the
batteries positive to positive and negative to
negative. This also applies when connecting a
battery charger.
5•4Engine electrical systems

Mitsubishi type
21Unscrew the pulley nut. To prevent the
shaft rotating, insert an Allen key in the end of
the shaft.
22Remove the spring washer, pulley, fan,
spacer and dust shield.
23Scribe an alignment mark along the length
of the alternator to facilitate reassembly of the
drive end housing, stator and rear housing.
24Unscrew the through-bolts and withdraw
the drive end housing from the rotor shaft.
25Remove the seal and spacer from the
rotor shaft.
26Remove the rotor from the rear housing
and the stator. This may require the
application of local heat to the rear housing
using a large soldering iron. Do not use a heat
gun, as this may result in damage to the
diodes.
27Unscrew the four securing bolts and
withdraw the diode pack stator assembly
from the rear housing.
28Unsolder the stator leads from the diode
pack terminals. Use a pair of pliers when
unsoldering to act as a heat sink, otherwise
damage to the diodes may occur (see
illustration).
29If the length of either brush is less than the
minimum given in the Specifications, the
brush box must be renewed.
30To renew the brush box, unsolder the
connection to the diode pack, and solder theconnection to the new brush box. Use a pair
of pliers as a heat sink to avoid damage to the
diodes.
31Examine the surfaces of the slip rings.
Clean them with a fuel moistened cloth, or if
necessary fine glasspaper and then the cloth.
32Solder the stator leads to the diode pack
terminals, again using a pair of pliers as a heat
sink.
33Refit the diode pack/stator assembly to
the rear housing and tighten the securing
bolts.
34Insert a thin rod (an Allen key is ideal)
through the hole in the rear housing to hold
the brushes in the retracted position.
35Fit the rotor to the rear housing and then
remove the temporary rod to release the
brushes.
36Reassemble the remaining components
by reversing the dismantling operations. Make
sure that the scribed marks are in alignment.
Removal
1Apply the handbrake, jack up the front of
the vehicle and support on axle stands (see
“Jacking and Vehicle Support”).
2Disconnect the battery negative lead.
3Working underneath the vehicle, unscrewthe nut and disconnect the main cable from
the starter solenoid (see illustration).
4Disconnect the ignition switch wire from the
solenoid.
5Unscrew the three mounting bolts and
withdraw the starter motor from the gearbox
bellhousing (see illustration).
Refitting
6Refitting is a reversal of removal.
1If the starter motor fails to operate first
check the condition of the battery.
2Check the security and condition of all
relevant wiring.
Solenoid check
3Disconnect the battery negative lead and all
leads from the solenoid.
4Connect a 3 watt test lamp and a 12 volt
battery between the starter terminal on the
solenoid and the solenoid body as shown
(see illustration). The testlamp should light. If
not, there is an open circuit in the solenoid
windings.
5Now connect an 18 watt testlamp between
both solenoid terminals (see illustration),
then energise the solenoid with a further lead
to the spade terminal. The solenoid should be
heard to operate and the testlamp should
light. Reconnect the solenoid wires.
On load voltage check
6Connect a voltmeter across the battery
terminals, then disconnect the low tension
lead from the coil positive terminal and
operate the starter by turning the ignition
switch. Note the reading on the voltmeter
which should not be less than 10.5 volts.
7Now connect the voltmeter between the
starter motor terminal on the solenoid and the
starter motor body. With the coil low tension
lead still disconnected operate the starter
and check that the recorded voltage is not
more than 1 volt lower than that noted in
paragraph 6. If the voltage drop is more than
1 volt a fault exists in the wiring from the
battery to the starter.
9Starter motor - testing in the
vehicle
8Starter motor - removal and
refitting
5•8Engine electrical systems
7.28 Stator-to-diode pack connections (A)
and brushbox-to-diode pack terminal (B) -
Mitsubishi alternator8.5 Unscrew the starter motor mounting
bolts
9.5 Starter motor solenoid continuity test
circuit
A Battery terminal
B Motor terminal
C Spade terminal
9.4 Starter motor solenoid winding test
circuit
A Battery terminal
B Motor terminal
C Spade terminal
8.3 Solenoid wiring connections on Lucas
M79 starter motor- CVH engine

41Locate the brush box over the
commutator, position the brushes, then fit the
nylon cover over the brushes. Route the brush
wiring into the locating channel, then secure
the brushes in the channels with the locking
clips and springs.
42Refit the commutator end housing,
locating the rubber block in the cut-out in the
housing, then secure with the two screws.
43Refit the spacers and C-clip to the end of
the armature shaft, then fit the commutator end
housing cap and secure with the two screws.
44Reconnect the wiring to the solenoid
terminal and fit the washer and securing nut.
Nippondenso type
45With the starter motor removed from the
vehicle and cleaned, grip the unit in a vice
fitted with soft jaw protectors.
46Unscrew the retaining nut and washer and
disconnect the wiring from the terminal on the
solenoid.
47Remove the two screws securing the
commutator end housing cap and remove the
cap (see illustration).
48Remove the C-clip from the groove in the
armature shaft, and remove the spring.
49Unscrew the two bolts and washers, and
withdraw the commutator end housing.
50Withdraw the two field brushes from the
brush plate, then remove the brush plate.
51If the brushes have worn to less than the
specified minimum, renew them as a set. To
renew the brushes, cut the leads at their
midpoint and make a good soldered joint
when connecting the new brushes.
52The commutator face should be clean and
free from burnt spots. Where necessary
burnish with fine glass paper (not emery) and
wipe with a fuel-moistened cloth. 53Position the brush plate over the end of
the armature, aligning the cut-outs in the
brush plate with the loops in the field
windings. The brush plate will be positively
located when the commutator end housing
bolts are fitted.
54Fit the brushes to their locations in the
brush plate, and retain with the springs.
55Fit the commutator end housing and
secure with the two bolts and washers.
56Fit the spring and the C-clip to the end of
the armature shaft, then smear the end of the
shaft with a little lithium-based grease, and
refit the commutator end housing cap,
securing with the two screws.
57Reconnect the wiring to the solenoid
terminal and fit the washer and retaining nut.
Note: The correct functioning of the spark plugs
is vital for the correct running and efficiency of
the engine. It is essential that the plugs fitted are
appropriate for the engine, and the suitable type
is specified at the beginning of this Chapter. If
this type is used and the engine is in good
condition, the spark plugs should not need
attention between scheduled replacement
intervals. Spark plug cleaning is rarely necessary
and should not be attempted unless specialised
equipment is available as damage can easily be
caused to the firing ends.
Removal
1Where necessary, for improved access
remove the air cleaner and/or the inlet hose.
2If necessary, identify each HT lead for
position, so that the leads can be refitted to theircorrect cylinders, then disconnect the leads
from the plugs by pulling on the connectors, not
the leads. Note that the position of No 1 cylinder
HT lead in the distributor cap is marked with
either a pip, or a number “1 “.
3On 2.0 litre DOHC carburettor models, the
location of the spark plugs and the close
proximity of the carburettor makes spark plug
access difficult, particularly when removing
the plugs from cylinders 2 and 3. It is
suggested that a 3/8 inch ratchet drive spark
plug socket with rubber insert and long
extension bar is used, possibly in conjunction
with a universal joint adapter. It is also
advisable to disconnect No 3 cylinder HT lead
from the distributor first, to allow some slack
for disconnection at the spark plug.
4Clean the area around each spark plug
using a small brush, then using a plug
spanner (preferably with a rubber insert),
unscrew and remove the plugs. Cover the
spark plug holes with a clean rag to prevent
the ingress of any foreign matter.
Inspection
5The condition of the spark plugs will tell
much about the overall condition of the engine.
6If the insulator nose of the spark plug is clean
and white, with no deposits, this is indicative of
a weak air/fuel mixture, or too hot a plug. (A hot
plug transfers heat away from the electrode
slowly - a cold plug transfers it away quickly).
7If the tip and insulator nose is covered with
hard black-looking deposits, then this is
indicative that the mixture is too rich. Should
the plug be black and oily, then it is likely that
the engine is fairly worn, as well as the mixture
being too rich.
8If the insulator nose is covered with light tan
to greyish brown deposits, then the mixture is
correct and it is likely that the engine is in
good condition.
9The spark plug gap is of considerable
importance, as, if it is too large or too small,
the size of the spark and its efficiency will be
seriously impaired. The spark plug gap should
be set to the figure given in the Specifications
at the beginning of this Chapter. To set it,
measure the gap with a feeler blade, and then
bend open, or close the outer plug electrode
until the correct gap is achieved (see
illustrations). The centre electrode should
never be bent as this may crack the insulation
and cause plug failure, if nothing worse.
11Spark plugs and HT leads -
removal, inspection and
refitting
5•12Engine electrical systems
10.47 Nippondenso starter motor brush assembly
1 Yoke
2 Solenoid connecting link
3 Pole shoe
4 Rubber grommet
5 Brush
6 Brush spring
7 Brush plate8 Commutator end housing
9 Bush
10 Spring
11 C-clip
12 Commutator end housing cap
13 Commutator end housing securing
bolt
11.9a Measuring a spark plug gap using a
feeler blade

Refitting
13Commence refitting by checking that No 1
cylinder is still at the firing point. The relevant
timing marks should be aligned. If the engine
has been turned whilst the distributor has
been removed, check that No 1 cylinder is on
its firing stroke by removing the No 1 cylinder
spark plug and placing a finger over the plug
hole. Turn the crankshaft until compression
can be felt, which indicates that No 1 piston is
rising on its firing stroke. Continue turning the
crankshaft until the relevant timing marks are
in alignment.
14Turn the rotor arm to the position noted in
paragraph 11. If a new distributor is being
fitted, and no alignment marks are present,
transfer the marks from the old distributor to
the new distributor.
15Hold the distributor directly over the
aperture in the cylinder block with the
previously made marks on the distributor
body and cylinder block aligned, then lower
the distributor into position. Again, if a new
distributor is being fitted, transfer the
alignment mark from the old distributor body
to the new distributor body. As the skew gear
drive meshes, the rotor arm will turn
anti-clockwise.
16With the distributor fitted and the marks
on the distributor body and cylinder block
aligned, check that the rotor arm is positioned
as described in paragraph 7 -if not, withdraw
the distributor, re-position the driveshaft and
try again.
17Refit the clamp, then insert and tighten
the bolt. Do not fully tighten the bolt at this
stage.
18Refit the distributor wiring plug, and
where applicable reconnect the vacuum pipe,
and refit the dust cover and/or rotor arm.
19Refit the distributor cap, and reconnect
the HT leads to the spark plugs and coil.
Ensure that the leads are refitted to their
correct cylinders.
20Where applicable, refit the screening can
to the top of the distributor and reconnect the
earth strap. On fuel injection models,
reconnect the air inlet hose, ensuring that the
clips are correctly aligned (refer to illustration,
Section 15, Chapter 4, PartB).21Reconnect the battery negative lead.
22Check and if necessary adjust the ignition
timing.
Early “Economy” models
Removal
23Removal of the distributor fitted to these
models is a similar process to that described
above.
Refitting
24Turn the crankshaft to bring No 1 cylinder
to the firing point, with the 16º BTDC mark on
the crankshaft pulley aligned with the pointer
on the crankshaft front oil seal housing, as
described above.
25Fit the new distributor to the engine as
described above, then proceed as follows.
26Cut the original distributor wiring plug
from the wiring loom. Make the cut close to
the connector.
27Strip back 10 mm of insulation from each
of the wires on the wiring loom, and on the
adapter loom supplied with the new
distributor.
28Solder the adapter loom wires to the
corresponding identically coloured wires in
the main loom.
29Carefully insulate each individual soldered
joint using insulating tape, then apply tape to
cover the join between the looms.
30Fit a new distributor cap (and screening
can, where applicable), and connect the HT
leads.31Connect the adapter loom to the
distributor.
32Start the engine, and adjust the ignition
timing to the value given in the Specifications
at the beginning of this Chapter. Work as
described above whilst noting that the
vacuum pipe must be left connected.
Note: During production the ignition timing is
accurately set using a microwave process,
and sealant is applied to the distributor clamp
bolt. Because the electronic components
require no maintenance, checking the ignition
timing does not constitute part of the routine
maintenance schedule, and the procedure is
therefore only necessary after removal and
refitting of the distributor. A timing light will be
required for this procedure. For details of
ignition timing adjustment in order to operate
vehicles on unleaded petrol refer to the
appropriate Section of this Chapter.
All models except 2.0 litre DOHC
1Before checking the ignition timing, the
following conditions must be met:
a)The engine must be at normal operating
temperature
b)Where applicable, the vacuum pipe to the
distributor vacuum unit or electronic
module (as applicable) must be
disconnected from the vacuum unit or
electronic module and plugged
c)The idle speed must be below 900 rpm
(isolate “idle speed adjustment” wire if
necessary)
d)Any earthed “octane adjustment” wires
must be temporarily isolated
2Wipe clean the crankshaft pulley timing
marks and the pointer on the crankshaft front
oil seal housing. Note that two alternative
types of pulley may be fitted (see
illustration).The desired timing values are
given in the Specifications. If necessary, use
white paint or chalk to highlight the relevant
timing mark(s) (see illustration).
3Connect a stroboscope timing light to the
No 1 cylinder HT lead, following the
manufacturer’s instructions.
4With the engine idling at normal operating
temperature, point the timing light at the
marks on the crankshaft pulley, and check
that the appropriate timing mark appears
stationary in line with the timing cover pointer.
Take care not to get the timing light leads,
clothing etc tangled in the cooling fan blades
or other moving parts of the engine.
5If adjustment is necessary, stop the engine,
slacken the distributor clamp bolt, and turn
the distributor body slightly. Turn the
distributor body clockwise to retard the
ignition timing (move the timing closer to TDC)
and anti-clockwise to advance the timing.
16Ignition timing (OHC models)
- adjustment
Engine electrical systems 5•17
5
15.12 Removing distributor driveshaft O-
ring - Motorcraft distributor15.10 Unscrewing distributor clamp bolt -
Bosch distributor
16.2a Highlighted timing marks - SOHC
engine with cast crankshaft pulley