'85-127 Alternator Wiring Question

[tbrodzeller]

OK guys...here is the first of many post regarding the electrical "gremlins" '85-127 has.

Alternator Issue
(I've tried 2 rebuilt alternators and 2 new voltage regulators...and they both do the same thing.)

The "field" wire sparks bad when I hook it up to the alternator (ignigition off).

It is also draining the battery...

When it's hooked up and the engine is running, the battery is charging...



I've tested the wiring - and it seems OK. The wiring going to the voltage regulator is correct...(depending on the position of the ignigition switch).


Is it possible I have 2 bad brand new voltage regulators?

What else would cause this?

[JACook]

If you've got Voltage on the regulator "F" terminal, with the ignition key off, you need to
check the "S" terminal. If there's Voltage there, the regulator is just doing what it's told.
You would need to investigate why that is. Have you looked at your ignition switch yet?

If there isn't, the regulator is defective. Usually the regulators only fail when there is a
problem in the alternator field circuit, or it's wiring.