Possible bad alternator???

-

kaytbugsdad

Well-Known Member
Joined
May 10, 2011
Messages
207
Reaction score
14
Location
Galt CA
I took my car out yesterday, drove fine to the store........ Came back out and went to start it, cranked slowly, and noticed to ammeter was reading -40 amps!!!! I shut it off, and started to see a small wisp of smoke coming from the alternator..... the wire coming from the alternator to the firewall was hot, as was the wire from the bulkhead to the starter relay..... I disconnected the negative on the battery (just happened to have a crescent wrench), and waited a little bit....... I connected the cable back up, car started right up and ammeter worked normally....... got halfway home (I only live about a mile away), and the ammeter went back to -40 amps....... I did the MAD ammeter bypass this morning, but it didn't change anything (kept getting some arcing while connecting the battery)..... Kept disconnecting things off the alternator, until I disconnected power from the alternator, that's when the arcing stopped..... Alternator shorted internally???? Possible bad connection at the bulkhead connector???
 
Yep I wouldn't fire it up anymore. More burnt wires in your future.

Similar issue a few years back. Hooked up battery and instantly fried fusible link. Disconnected battery asap. Alternator was pooched.
 
Removed alternator just a few minutes ago....... One of the diodes is fried beyond recognition, I checked the rest of the wiring for the charging system..... Everything looks OK!!!! All electrical tests show low resistance in the wiring and no bare wiring at all..........Gonna order an alternator in the morning..... Thanks guys!!!!
 
-
Back
Top