When I drive at night I can see this the best, but it happens all the time. I notice a drain on the battery, both on the gauge and by seeing the lights dim. This happens intermitantly. With the same frequency, I also see an over charge (lights get really bright, and the gauge is over in the plus range).

When I bought the car the previous owner had replaced the original alternator with a chrome one (looks nice). I've heard that these are not the best, and was wondering if you all think this could be my problem and I should switch back to the original one?
Thanks,
Glenn

First thing to check is the alternator belt. If it's loose it can give you some of this trouble. Second, check out your voltage regulator. I think it's internal on a '75 alternator; take the alternator to the parts store and have the output tested. (somebody want to check me on this one?)

good luck

John

I agree with John, have the alternator checked. If the alternator checks good, you may also want to check the belt. the wrong width belt could slip when under load, causing fluctuations in the voltage.

Good Luck!

Dave

Make sure your battery connections are clean ! If they are dirty the sensors on the alternator may not detect that the battery needs charging. ALso check the connectors to the alternator - I found one on mine that was broken - replacing it solved the problems I was having with my alternator.

Good Luck !

Thanks everyone, I'll check it out tonight.