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Alternator Diode Failure- Fixed? 900 1993

I had a severe drain on my battery with the ignition off. It was to the point where, using a VOM, I could see the voltage decrease by .02 per second. I could detect no current drain using the ammeter between the neg. post and the neg. cable. However, when I disconnected the alternator, the voltage drain stopped. I read elsewhere that diodes in the alternator can fail and cause battery drainage. This is what I think happened here. Despite the battery drain, the alternator was putting out about 14.40 voltage.

So, since I live in Annapolis, I called up Brian at http://www.volvousedparts.com/, which is located in Deale, nearby. He had a replacement Denso alternator for $50. I put it in, hooked it up and now have steady 12.6 voltage at the battery with the ignition off. The used alternator puts out about 14.35 volts while running.

My questions are these:
(1) While my problem seems to be fixed for the moment, is it fixed for good or should I be concerned about this alternator, which is out of a 1994 car?
(2) And if the brushes or regulator fails (given the age of the alternator), can it be rebuilt given that it's Denso and not Bosch?
(3) What should I do with the old alternator?

Thanks.
--
1993 945 NA






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New Alternator Diode Failure- Fixed? [900][1993]
posted by  Jas945  on Sat Jan 27 12:27 CST 2007 >


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