The 67 Special was doing fine, the amp gauge worked fine. I changed the alternator, just for looks, nothing wrong with the old one. But after the change, when I start it, the amp gauge, a Sun in a 3 gauge panel under dash, looks fine for a few seconds, then starts whipping back and forth very fast. I checked the ground and feel sure it is fine, bit ran an extra ground wire just trying to figure it out, no change at all. It still has the regulator in the system. Any ideas? Thanks
Thanks. Lights flickering at the same rate as the needle flutter? Check voltage across battery terminals with headlights off and with them on, at idle, and then the same thing at 2500 RPM. Post output voltage, at all both idle and RPM with lights off and on, and if there is any flickering. And what the ammeter numbers indicate. Another thing is to feel if the regulator is "buzzing" or clicking.