Range Rover Classic has a 12v negative earth system, charged by
an alternator. The battery is mounted behind the right hand head
lamp. In carburetor engined versions (up to 1985) there was an
identical mounting behind the left hand headlamp for an auxiliary
battery. That space was occupied by the air filter in the later
fuel injection variants.
battery is unusual in respect of the position of it's terminals
in the battery case, which are the opposite way round from most
battery types - negative nearest the wing valance.
Before doing any work on the electrical
system, you should disconnect the battery.
This is best done by disconnecting the earth lead.
This means that in the event of
a metallic object being dropped across the exposed battery terminal
and the bodywork the system is just reconnected, rather than the
battery being short circuited which can result in an explosion.
started flickering and showing no revs. Periodically the warning
lamp on the dashboard would come on. These symptoms occurred both
together and separately. In between, everything appeared normal.
I therefore decided to overhaul the alternator,
with a view to replacing the brushes.
Special tools required: 5mm and 5.5mm
1/4" socket or box spanners
The first thing to do is to identify the type
of alternator from the plate on the top. Remember that vehicles
fitted with air-con have the alternator on the left, those without
on the right. Thus there are right and left handed versions!
I then discovered from my local autoelectrician
that they can be fitted with blade or bolt-on connectors. As the
brushes for the two types are different, it's a help to take a
photograph to show when ordering the brushes.
So mine is a Lucas A133-65, left-hand, with bolt-on
The big fat brown wire on the
right hand screw terminal is the connection to the battery.
The white/black lead on the small
screw terminal on the left (it's actually one of the brushes)
goes to the warning light.
The spade terminal on the top
left with the single wire goes to a suppressor.
The spade terminal on the top
right with two white wires goes to the tachometer and also to
a surge protector (which looks to me just like another suppressor!)
I thought that once these leads
had been removed, with the two cover screws, that I could remove
the cover in situ. I was wrong!
The suppressor and surge protector
are held on with a 10mm head bolt, which is very much easier to
get at once the alternator is off the car. I also think refitting
the bolt would be extremely difficult with the unit in situ.
Once inside, I found that debris
from brush wear had produced a large volume of black conductive
dust inside the brush/slip ring housing, which had collected in
the 7-9 o'clock position. At the time, I believed that this had
been responsible for my problem, but subsequent events proved
The brushes are held by three
When removed, they showed relatively
little wear after 50,000 miles and were well in excess of the
10mm minimum length.
The bolts retaining the brush/slip
ring housing require a 5.5mm socket or box spanner, after which
it's relatively easy to clean the area.
The book states that fine sand
paper should be used to clean the slip rings if necessary, not
emery cloth (presumably it can leave aggressively abrasive particles)
and a petrol soaked cloth for wiping dust away.
However, in spite of all this
effort the problem recurred and eventually proved to be a faulty
regulator, which was replaced for the sum of £27 (a new
alternator would have cost over £200 !)