I have alternator trouble with my 93 legacy. I put in a new battery thinking that was the problem, then had the alternator rebuilt, after which it went bad (or something caused it to go bad). After the guy rebuilt it the second time it went bad again. Any suggestions? If there is a short, any suggestions of where to find it?

Are you sure it is the alt? And did you have the alternator Load tested with the new battery? If you put a new or rebuilt alternator on a dead battery, it can cook it fast. You need to do the replacement at the same time, or at least close to the same time.

 

I would have the units load tested, as well as check all the cables for the charging system. Maybe you are electrifying a dead mouse under the hood for no reason.

The diodes in the rectifier in the alternator might be fried. Did the alternator-rebuilder check the diodes?

When the car first stalled, I suspected it might be the battery since its life was about over anyway. New battery installed, the light was still on, so I had it checked out and the alt was not charging, hence the first rebuild. Upon putting the rebuilt alt back on, the light was off (I ASSUMED all okay and recharging as normal), but the same day the light came back on, another test soon indicated it NOT charging, and hence the second rebuild job. After that, it lasted a very short time with the light off, then it came on and the alt has since gotten very hot. When I unhook the main plug, it starts okay and the alt does not get hot. I'm not sure about the diodes being replaced. I'll look into it, though. Thanks. Any more ideas or tips are greatly appreciated!