LRA 383 Alternator Wiring Query

[bigdawgv8]

Hi All,

After a few years laid up in my garage I've finally got my V8 Morris truck up and running.
Unfortunately after the long lay up the alternator was checked and found to be faulty, so that has been rebuilt.

There are 2 large threaded studs on the back (not connected together) and 2 normal size spade terminals

Does anyone have a wiring diagram for it or can anyone tell me what goes to what?

Thanks for any help you can give me.

Cheers

Martin

[ChrisJC]

Do you know what the alternator was originally fitted to?

Chris.

[bigdawgv8]

Hi,

Yep, sorry forgot to say.

It's a Lucas LRA 383 from a V8 Range Rover.

[bigdawgv8]

Hi,

Can anyone advise?

Thanks

[DaveEFI]

I dunno this particular alternator. Are the two screw terminals the same size?
If so they are probably parallel outputs to allow the use of two smaller cables rather than one thick one. The spade terminals - one will be the warning light, one a tachometer output for a diesel. If you look closely at the cover, they are usually marked.

But just an informed guess.

[Eliot]

If one is an 8mm stud, thats the thick one to the battery and if the other stud is smaller(approx 4mm) that is the ignition light wire.

[bigdawgv8]

Thanks All,

I do know that the 2 threaded terminals are not connected together so have 2 different uses.

There is nothing shown on the case to give any clues.......

Thanks

[Denis247]

It's probably a "Battery Sense" connection.

Alternators can be "Machine Sense" and have just an output or "Battery Sense" and have a regulator input. Normally taken to the solenoid or somesuch but I believe it can also just be connected to the output terminal (thick post) effectively making the alternator "Machine Sensed".

Here's a site that explains in more detail.
http://www.mgb-stuff.org.uk/electricstext1.htm