peterc

Hey Darryl, Thanks for suggestion! I never thought of scanning the diagrams and enlarging them. we'll see just how good my scanner is

I seem to have a short somewhere in the electrical system since the voltmeter continues to read 12 volts even with the key out of the ignition and I get massive overcharging with the engine running (already fried 1 battery). I think I've isolated the problem though. There are 4 fusible links on the passenger-side inner fender wall. When I remove the one thats closest to the front of the car/farthest from the engine, the voltmeter shows normal charging when the engine is running and drops to zero when the key is removed (just the way it should) and the battery stays charged overnight. The wiring diagrams in the Haynes manual require an electron microscope to read so I don't know what all runs off this circuit. I do know that the 4 way flashers and the running lights on on it but since they all operate properly (all same intensity, no flickering) I'm thinking the short might lie elsewhere. Anybody know where to get wiring diagrams that you can actually read or know what else is controlled by this circuit?

Thanks for the info axrph. I'll check and make sure that I wired the voltmeter up properly (wouldn't be the first time I installed something incorrectly. After the rebuild I actually installed the Airbox backwards. And surprisingly, the car started!! It would idle o.k but stall when I tried to give it any gas. Took about an hour before I realized what I had done According to the voltmeter I'm definitely overcharging, with readings from 12-18+ volts, depends on how high the engine is revving. Another question. When the key is NOT in the ignition, what should the vo;tmeter read? On all other cars I've owned the voltmeter goes to 0, but the 280's still reads 12 volts. So I'm assuming the circuit is still live.

After my beloved '72 finally succumbed to the heartless rust gods (my fault for living in Ottawa, Canada) I went looking for a replacement. Eventually I was able to get my hands on a '77 from So/Cal with a solid body, but not running (warped head/blown head gasket). After doing the rebuild and putting everything back together I'm experiencing a problem with the charging system. There is a little red light in the voltmeter which remains 'on' whether the car is running or not (it even stays on when the key is removed from the ignition). I'm assuming that this is not normal?! When the car is running the voltmeter continually overcharges, in proportion to the engine speed. Sounds like the voltage regulator, but I can't determine from my Haynes manual whether the '77s had an internal (in the alternator) or external regulator. If it is an internal regulator thats gone, can it be replaced without replacing the whole alternator?