The Stovebolt Site Forums The Shop Area The Electrical Bay Volt gauge

On my '63 Chevrolet truck when I turn on the turn signal, my volt gauge needle jumps from 12-10 on the gauge. If I turn on the electric fan the volts drop to 8-10 on the gauge and stays there. NOW it gets interesting, I put a charging system tester on at the battery, with the truck running the charging system shows a charge of 14-15 volts. What do I need to do to trouble shoot these problems?

have your tester on the battery,vehicle running,watch the reading when a friend turns on a signal and/or the fan.does the fluctuation happen at the tester?Could be the volt gauge in the dash is wrong.As long as the alternator compensates for the voltage draw you will be fine

Dendo,

A charge voltage of 14.8 is still within normal high limits so I wouldn't worry about that. I would do as BC52 recommends and see what that meter attached to the battery reads when you do your little draw down test.

I don't know what kind of charging system a '63 has, but it might not be able to see system voltage well enough to react and kick in in short order. Your dash volt meter, however unlikely, could have a very poor connection to the charging system. If you compare a test meter reading at the battery with the dash gauge reading it should give you a direction to go.

If your rig uses a voltage regulator with either a 10dn alternator or a generator, I would be real suspicious of it.

I would also look at the brushes on either alternator or generator.

Stuart

Does your truck still have the factory wiring or has it been re-wired? Sounds like your charging system and battery are fine but I wonder if the wire feeding the fuse panel is big enough, especially if your running extra electrical circuits that weren't in the truck originally.