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Lil bastard · 07-24-2008, 10:20 AM

Could be any number of things... but when was the last time your battery was changed?

A poor battery can kill an alternator. If 3 or more yrs. old, and/or you've had multiple total discharges (being a used car, presumably you have no knowledge of the previous history of the battery), I would always replace the battery if having any electrical issues such as an alternator going bad. In addition to making the alternator work harder, the battery may not be functioning properly in it's secondary role as a current/voltage stabilizer. Without this, the alternator can spike upwards of 40 volts which is sure to kill the diodes.

Of course, it could simply be that the 2nd alternator failed. These types of rebuilds that you find at the mega-autoparts chains are usually done 'assembly line' style and IMHO aren't near as good as the individual ones you get from a small private rebuilder.

07-24-2008, 10:20 AM	#2
Lil bastard Registered User Join Date: Feb 2008 Location: Du Monde Posts: 2,199	Could be any number of things... but when was the last time your battery was changed? A poor battery can kill an alternator. If 3 or more yrs. old, and/or you've had multiple total discharges (being a used car, presumably you have no knowledge of the previous history of the battery), I would always replace the battery if having any electrical issues such as an alternator going bad. In addition to making the alternator work harder, the battery may not be functioning properly in it's secondary role as a current/voltage stabilizer. Without this, the alternator can spike upwards of 40 volts which is sure to kill the diodes. Of course, it could simply be that the 2nd alternator failed. These types of rebuilds that you find at the mega-autoparts chains are usually done 'assembly line' style and IMHO aren't near as good as the individual ones you get from a small private rebuilder. __________________ 1990 Porsche 964 Carrera 4 Cabriolet 1976 BMW 2002 1990 BMW 325is 1999 Porsche Boxster (gone, but not forgotten) http://i933.photobucket.com/albums/a...smiley-003.gif Never drive faster than your Guardian Angel can fly! Last edited by Lil bastard; 07-24-2008 at 10:29 AM.