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Discussion Starter #1
I recently purchased a 69 Camaro with a 396 that had some electrical gremlins that I'm slowly but surely working through, such as inaccurate fuel gauge and amp gauge on the console, but I have a couple of questions; first the dumb question - What's the best way to tell if this 396 has a generator or an alternator?

Next: After the car sat for about a month and a half, I found the battery to be dead; I hooked up the battery charger and in a matter of seconds it was up and running. Drive the car, shut it down, go in store, come back out and battery is dead. I noticed, while I was getting a jump that the red wire coming out of the back of the generator (or alternator - see dumb question above) goes directly to the battery positive post. I thought it had to go to the regulator, then to the battery; any ideas??
 

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If it's made out of Aluminum it is most likely an "Alternator" ;)
Alternators were standard equipment on most vehicles after the mid-60's ...

The 'Red' wire from the main terminal of the alternator is the "Charge" wire and should go directly to the battery - BUT, this should be via the junction/splice in the wiring below/near the Regulator, but not 'through' the regulator, if the original alternator and system is being used ...
If someone has wired it directly to the battery, you either have a different alternator system now or someone was 'trying' to fix something - hard to tell without seeing it and knowing more about it ...

Great information on original and upgraded system here - http://www.madelectrical.com/electricaltech/chevymain1.shtml
 

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Discussion Starter #3
Thanks John, it is definitely an alternator, I ran the part number it's a Powermaster Gm 12si Alternator 140 amp (Chrome Pm37294); the problem is that the white, and blue wire connections that are supposed to go from the alternator to the voltage regulator are not on the alternator. I can follow schematics, but this one is driving me nuts, I'm sure that is why the amp gauge is not showing a charge...
 

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If it's missing the additional wires to the unit then it's most likely been changed to a "One-Wire" unit :sad:

You can read up on them and the 'fix' on the same site I linked.
Just go to the 'Electrical Tech' section on the header above, and read the 'One wire vs. Three-wire' section ;)
 

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Complementing John's suggestions, most likely, you have a one-wire alternator.
A PO (previous owner) wired the alt BATT stud directly to the positive battery post, shorter route, than going back over to the horn relay buss bar, then through the red wire to the battery junction block to the pos cable pigtail/fusible link.

The OE ammeter has two leads, one black and the other black/white and a lead is connected to the horn relay buss bar and the other lead connected to the battery junction block. The ammeter indicates the current flow and shows it a s a discharge, alt off, or charge, alt on/running.

With the alt hooked as mentioned, the ammeter will not indicate a charge, but would show a discharge. You would need to wire the red wire from the alt BATT back to the horn relay buss bar for the ammeter to indicate a charge - only if an OE ammeter is being used.

Also, most one wire alts need to be revved to start to work. You might give it a try.
 

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Discussion Starter #7
Thank you guys. I am getting a new under dash harness installed and eventually will redo the engine harness; in the mean time, I think I will wire it as suggested, but what about the other 2 wires in the 3 wire system. That's where the confusion begins because the article referenced by John leaves that part out...
 
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