76mike

Tried to start the corvette up last night to go somewhere and it wouldn't start. Had to take my dad's 96 tercel. THIS MUST BE FIXED! I just replaced the alternator like 2 weeks ago because the voltage was low, but after I replaced it the voltage was about 14v. I haven't checked since then, but what else could go wrong? It's like the battery isn't charging properly..... is there anything else in the charging system besides the internal voltage regulator in the alternator?

Techno

Diodes to change AC to DC.
Before digging though make sure thats whats wrong.

76mike

I jumped the car and checked the voltage again and it was reading 11.5v-ish. So the alternator is dead. Could anything have done this or did it just go bad?

79 vette head

i also have a battery drain but my alt. is good,new belt,if i let the car sit for a few weeks i must jumpstart the car. as soon as i put the cables on she starts rite up??? any help

TheKomoman

Where did you check the voltage, at the battery or at the back of the alternator? The output voltage of the alternator should definitely be north of 14v, more like 14.6-14.8. I would take that battery somewhere to get load tested, especially if you're seeing lower volts at the battery than at the back of the alternator. Since you replaced the alternator the next logical step in the chain is the battery. While it's possible the alternator was damaged in 2 weeks or perhaps wasn't rebuilt/built properly the battery seems more likely.

76mike

Ok so I took the alternator down to get another one (warentees are good things) and the guy tested it at over 15v. He said "Sorry" and that was the end of it. How could I be getting 11.5v at the alternator in my car and he gets 15v at the tester? I mean I suppose that my belt could have been loose or something... any ideas??