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Discussion Starter #1 (Edited)
The back story is- I had an ebay 150 amp one-wire alternator.
The new battery was draining very quickly while sitting and driving, and different tests for drains and shorts and whatnot yielded unclear results.
I was told the "goofy" one-wire alternator may be draining the battery; bad voltage regulator
The alternator-fixer-guy replaced the one-wire with a standard 3g regulator and said to wire it up with 3 wires.
I didn't want to. I like my clean wiring.
I replaced the 3g regulator with what I thought was another one-wire regulator.
Reinstalled alternator, but forgot to take out the pin from the brushes.
As soon as I hooked up the battery, I got a click from the alternator and smoke.
And yes, I took it off and did it again; just to make good and sure I broke something, and I got another click with even more smoke.
I ran the car, and (SURPRISE!) it wasn't charging.
I noticed that I neglected to remove the pin from the brushes.
Retested: no smoke, but no charge. Later to find that the brushes' wires were... no longer connected.

And then:
I agreed with the alternator-fixer-guy.
I went to the junkyard and got a Taurus 3g alternator.
I replaced the brushes and regulator with the new ones the fixer-guy put on the original alternator.
(This is a much longer story than I had anticipated...)
Rewired the alternator wiring with 3 wires: Big battery wire, green to keyed 12v (labeled "ALT EXCITOR" from the wiring kit... exciting!), yellow looped to alt post.
I reinstalled the alternator and got just a click; no smoke.
Ran car, no charge.
AH! I, again, neglected to remove the pin from the brushes (genius.).
Ran car again, still no charge.
I looked online to price a new alternator.
I wrote this.

Okay, the big question is:
Is my issue all because of the pins in the brushes? Can that kill an alternator, and will new brushes (and removing that pin before adding 12v) solve my problem?

5,633 Posts
The pins short the brushes out to the case of the alternator. The braided wires that connect the brushes usually burn up.

669 Posts
I just put a 3g on my '69. Did you put a 560 ohm resistor in line between your green wire and keyed 12v? In my case i went to a u-pull yard, paid $17 for the alternator with a one month warranty. Went straight to Advanced Auto and had them bench test it. Tested good. Didn't bother replacing brushes or regulator. Who cares, if they go bad, i'll just go pull another one for $17. Have to admit though with that 3G, I can idle with A/C, aux cooling fan, door open, radio on, hi-beam, brake lights and still get 14.7 volts!
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