Now hold on to your britches.... I tried another alternator that was proven good - when I had my old wiring harness on there. Since changing harnesses, it's charged fine. Never was discharging a problem. As far as regulators, I've tried 3. Oh, I've tried 3 batteries also. Again, all while it was overcharging. It's never discharged before (this was sucking the life out of the battery in 12 minutes)