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5•4 Engine electrical systems
4 Battery - removal and refitting
1 Disconnect the battery negative (earth) lead.
2 Disconnect the battery positive leads. These
may be protected by a plastic cover. Do not
allow the spanner to bridge the positive and
negative terminals.
3 Release the battery hold-down clamp. Lift
out the battery. Keep it upright and be careful
not to drop it - it is heavy.
4 Commence by placing the battery in its tray,
making sure it is the right way round. Secure it
with the hold-down clamp.
5 Clean the battery terminals if necessary
then reconnect them. Connect the positive
lead first, then the negative lead.
5 Alternator - testing on the
vehicle
1 Should it appear that the alternator is not
charging the battery, check first that the
drivebelt is intact and in good condition and
that its tension is correct. Also check the
condition and security of the alternator
electrical connections and the battery leads.
2 Accurate assessment of alternator output
requires special equipment and a degree of
skill. A rough idea of whether output is
adequate can be gained by using a voltmeter
(range 0 to 15 or 0 to 20 volts) as follows.
3 Connect the voltmeter across the battery
terminals. Switch on the headlights and note
the voltage reading: it should be between 12
and 13 volts.
4 Start the engine and run it at a fast idle
(approx 1500 rpm). Read the voltmeter: it
should indicate 13 to 14 volts.
5 With the engine still running at a fast idle,
switch on as many electrical consumers as
possible (heated rear window, heater blower
etc). The voltage at the battery should be
maintained at 13 to 14 volts. Increase the
engine speed slightly if necessary to keep the
voltage up.
6 If alternator output is low or zero, check the
brushes. If the brushes are OK, seek expert
advice.
7.2 Removing the voltage regulator/brush
carrier
7 Occasionally the condition may arise where
the alternator output is excessive. Clues to this
condition are constantly blowing bulbs;
brightness of lights vary considerably with
engine speed; overheating of alternator and
battery, possible with steam or fumes coming
from the battery. This condition is almost
certainly due to a defective voltage regulator,
but expert advice should be sought.
8 Note that the alternator voltage regulator
can be renewed without removing the
alternator from the vehicle. The procedure is
part of brush renewal.
6 Alternator - removal and
refitting
1 Disconnect the battery negative lead.
2 Disconnect the multi-plug from the rear of
the alternator. It may be secured by a wire clip.
3 Slacken the alternator adjusting and pivot
nut(s), bolt(s) and washer(s) (see illustration).
Swing the alternator towards the engine and
slip the drivebelt(s) off the pulley.
4 Support
the
alternator.
adjusting and pivot nuts, bolts and washers,
noting the fitted positions of the washers. Lift
out the alternator. Do not drop it, it is fragile.
5 Refit by reversing the removal operations.
Tension the drivebelt(s) then tighten the
adjustment strap bolt followed by the pivot nut
and bolt. If there are two pivot bolts, tighten
the front one first.
6 Refit the multi-plug and reconnect the
battery.
7 Alternator - brush renewal
1 The alternator brushes can be inspected or
renewed without removing the alternator from
the vehicle, but disconnect the battery
negative lead first.
2 From the rear of the alternator remove the
two screws which secure the voltage
regulator/brush carrier assembly. Withdraw
the assembly (see illustration).
3 Measure
the
length
protruding from the carrier (see illustration). If
they are worn down to, or below, the minimum
7.3 Measuring brush protrusion
6.3 Alternator mounting details
A Large washer
B Small washer (not always fitted)
C Mounting bracket
D Alternator
Some models have a single pivot bolt
specified, the old brushes will have to be
unsoldered and new ones soldered into place.
Some skill with a soldering iron will be
required; excess heat from the soldering iron
Remove
the
could damage the voltage regulator. When
fitted, the new brushes must move freely in
their holders.
4 Clean the slip rings with a cloth moistened
with methylated spirit (see illustration). If they
are badly burnt or damaged, seek expert
advice.
5 Refit the assembled brush carrier/voltage
regulator and secure it with the two screws. If
the alternator is on the vehicle, reconnect the
battery negative lead.
8 Starter motor - testing on the
vehicle
1 If the starter motor fails to operate, first
check that the battery is charged by switching
on the headlights. If the headlights do not
come on, or rapidly become dim, the battery
or its connections are at fault.
2 Check the security and condition of the
battery and starter solenoid connections.
Remember that the heavy lead to the solenoid
of
each
brush
is always "live" - disconnect the battery
negative lead before using tools on the
solenoid connections.
7.4 Clean the slip rings (arrowed)
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