View Full Version : Polarizing a Generator

03-14-2004, 01:46 AM
I'm looking for some information regarding polarizing a generator for a Tiger MK1A. I recently had it rebuilt. I have the shop manual, but the directions there seem somewhat vague. A detailed instruction with specific terminal connections would be appreciated. Thanks.

03-14-2004, 04:35 AM
Hello Mutha 289,
are you doing a polarity change, if not it shouldn't need polarising.
The procedure is to connect the generator as per the manual, but leave off the field connection, (If it is a Lucas Dynamo) the smaller of the two spade connections. Connect a wire to the battery live side and with the engine running, touch this wire to the field terminal a couple of times. The generator should now be polarised.

Alec graemlins/cheers.gif

03-14-2004, 11:54 AM
I'm not changing the polarity of the generator, but I've been told (and have read several articles including the service manual) that all say a rebuilt generator requires polarizing.

So is the method you reccommended for changing the polarity or simply polarizing a rebuilt generator?

By the way, after installing the rebuilt generator I still have an illuminated ignition warning light. images/icons/confused.gif

03-14-2004, 01:25 PM
Hello Mutha289'

I would have assumed that a rebuilt unit would be tested and so the polarisation would already be carried out. Anyway, the method I outlined polarises the generator to the car whether the polarity has been altered or not. It simply aligns the generator polarity to the car.
If you have a red light then it is possible that the regulator also needs attention.

By the way, a simple test of a generator is to connect the field and armature connection together then apply voltage to those terminals and the case. If it is functional the generator will drive, i.e. become a motor. Obviously the fan belt should be removed.

Alec graemlins/thirsty.gif