Hey guys, my buddy has an 89 chevy 1500 with the TBI 350. He has the 2 wire alternator + the positive wire and we cant get it to charge up for the life of us.... It use to charge just fine before he blew the motor. He got a new motor and swapped it in and I got it running for him again but now for some reason it wont charge and it is the same harness AND a brand new bench tested alternator. With my multimeter it shows like 11.9 on the back of the alternator which is just because its hooked to the power block on the firewall and thats what the battery is at. I have tried it with the stock harness and with 12v going to plug 1 and nothing to plug 2 so its using its internal regulator and still nothing... Am I missing something? The block has a ground wire going directly to the battery too if that would matter? Though the alt. is an aluminum case.

 

No ideas huh? :/

 

you might have a internalally shorted battery grabbing up all the alternater will put out. Giving you a faults/ positive reading on your DVOM. Run the vehicle with battery + disconnected and take another reading.