Help!! My alternator is killing my battery.
 

i have installed a 120 amp high output alternator on my 74 chevy truck. now my battery is being drained by the alternator when the truck is not running. otherwise it charges fine. I ran the red wires on the alt plug back to the battery wire like someone told me. i suspect that is the problem. if i unplug the alt it does not kill the battery.

Here is wiring diagram for a internal regulated alternator.

http://www.rowand.net/Shop/images/al...o1985Buick.jpg

I GURANTEE you have your wires crossed on the voltage regulator. I had the SAME problem a few weeks back. Swap the wires on the voltage regulator and you'll be good to go. I think it's 12v+ constant at A and 12v+ switched at B.

This might solve my problem too....been running the wrong direction I think...

Thanks guys....check it out tomorrow

Yea myne to, but what is the voltage reugulator and were is it located?

T T T

The voltage regulator is inside the alternator. It is directly under the #1 and #2 location. Look through the slots and you'll see it. The part regulates the voltage out of the alternator. If it did not the volts would go through the roof at high RPMs. Drop like a rock at idle.

What is the #1 and #2 location?

Says on the Alternator. #1 is drivers side pin, #2 is passenger side pin.