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MG MGB Technical - O/T: anyone help with Alfa electrical problem?

One of my colleagues runs an Alfa Duetto. The battery is discharging when the car is used however. He has rebuilt the dynamo and has ruled that out, but now the indicators have stopped working. Anyone with some electrical knowledge have any suggestions? Sorry for being non-MG, but I was telling him how useful this site was, and I guess such a problem could be generic across all classics!
Thanks in advance
Martin Port

Hi.

The problem is that his battery is surrounded by the wrong type of car.....

But seriously.. a faulty voltage regulator box could be the cause of the discharge problem.

Don
Don

Apparently it's a new regulator box - but I guess that could be faulty. Would that cause the indicators to fail?
Martin Port

Martin,

If the workshop manual for the Alfa is as complete as the one for an MGB (my alfa 164 manual was 2 leaver arch file) then it will have information about the testing of the regulator and the dynamo. Your colleague will need a multimeter. If he hasn't got a workshop manual try using the instructions and spec's from the mgb manual.

Alternativly he could write to the questions page in Classic Cars!!!

David
David Witham

As some older Alfa's have Lucas electric components, you may not be very far OT!

On the following link there are some subject (Lucas, shorts, etc.) that might be of interest to your "collegue" (why don't you admit owning this Italian crap, LOL!)

http://www.alfaclub.org/tech_library.htm

I presume you checked that the generator is working? Did you "flash" it to polarise it correctly?

From the above link comes this description when changing polarity but "flashing" should also be done after rebuild or long time storage. The new regulator could have been toasted if it was polarised incorrectly?

<<With the engine off and the battery connected, "Flash" terminals A and D together with a short jumper wire. This will repolarize the generator for the negative-ground operation. One "Flash" should be enough, but to it twice to make sure.

If you do not re-polarize the generator, residual magnetism in the armature and pole pieces will cause it to come up to its previous pull-in voltage in the wrong (negative) direction.

Regulator cut-out points can take a beating if this happens.>>

Good luck,

Willem "armchair expert" van der Veer
Willem van der Veer

How dare you suggest I own this car! Seriously though - it's not mine - I'm BMC through and through (67 MGB and 68 Mini Super DeLuxe)!
Thanks for the suggestions. I'll pass them on.
Martin Port

Martin, couldn't resist, maybe you should read this one to on the MGA board:
http://www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgbbs&access=&mode=threadm&subject=6&thread=200506061021544788&source=L&anc=2005-06-1009:44:37#2005-06-1009:44:37
Willem van der Veer

I would imagine that many of the suggestions on paul hunts website may well help here too!

~PHIL
Phil

This thread was discussed between 09/06/2005 and 12/06/2005

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