[BAD415]

I bought a rebuilt date coded 32amp alt for my Chevelle.It shows a - drain on my gauge until I rev it to about 2000 rpm then it shows a charge, and is fine at idle and driving. I have to go through this ritual every time I drive the car. I thought it might be the voltage regulator so I bought a new one. I put my Delco Remi cover on it to look original...heh nothin but a pc board inside now a days. Anyway I still had to rev to get it to charge. Its not a real problem for me but I'd hate for my wife to be driving it and kill the battery. Any ideas what might be going on, and possibly a tweak I could make? Wrong pulley size maybe?

 

[SNFU Mobile]

You could have too large a pulley on there, but it just sounds like that is the excitation point for your alternator.

I'm not totally up on the old style alternators - but I do believe that there is an excitation wire that flashes the field - this might not be hooked up right, if you have it.

 

[Peter F.]

Check the brown wire which is the #4 connector on the regulator. That comes from the a resistor under the dash and provides some current to the field to make the alternator turn-on when it begins to spin. You should be able to connect a test light between it and ground and the light should come on when you turn on the key.

I assumed you have guages in the above. If you have a alternator light the brown wire comes from it. Then, grounding the wire should make the alternator light come on.

Peter