Thread: Wierd charging issue...

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Guys,
I picked up a '69 Nova that was setup for drag racing with a master cutoff switch, two batteries in the trunk, Painless wiring harness (along with stock) and, among other things, a lot of wires lying in the passenger floor from an MSD 7600 system that was never "appropriately cleaned up." Anyway, I noticed that the volt gauge was only reading about 12 volts while running, and didn't increase with RPM. I began tracing wires (they're everywhere), and noticed that the 3-wire GM alternator had the exciter wire going to a switch on the Painless box. The other smaller "hot" wire follows the normal path to the horn relay switch. The larger wire on the alternator terminal went NOWHERE. I thought it would be an easy fix and wired it back to the stock location and the volt meter DROPPED. I then tried wiring it to the starter relay and the volt meter showed a similar drop. The alt is putting out about 14 volts at the terminal while running, but the charge isn't getting back to the batteries in the trunk.

I'm starting to look for voltage drops in the wiring, and I may even hook the alt to the main power block on the radiator support. Any other ideas? When my brother revved the motor, the 30-amp fuse in the Painless switch (the exciter wire) actually blew - twice!

I'm a little leary of sending any major charge through the very expensive MSD 7600 system, so I'll welcome any comments.

As always, Thanks!

Hobo

The smallest wire is actually your trigger and hooked up to a switch, the other two can be tied together and sent back to batt pos. at the starter. Hank

Buy a new alternator, or get another kit for that one. It's cooked.

smallest wire... idiot light bulb, key-on power.
sense wire... connect to 12volts near fuse panel, but can be patched to charge post.
charge wire... lug on starter solenoid