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Discussion Starter #1
I did a 3G conversion on my 67 Coupe with 302 yesterday. This morning the car was completely dead. I had to use a jumpbox to statt it and that barely worked. What could be causing this draw?
 

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Is this new?, Rebuilt? Higher amp aftermarket?
I'd start by verifying your wiring is right if that is correct I might suspect a bad regulator which I believe is integrated on that Alternator?
 

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Discussion Starter #5
Is this new?, Rebuilt? Higher amp aftermarket?
I'd start by verifying your wiring is right if that is correct I might suspect a bad regulator which I believe is integrated on that Alternator?
The alternator is a brand new 3G 130 amp alternator. It is possible that I wired it wrong but I just followed a diagram like the one above.
 

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Discussion Starter #7
It goes to a switched 12V source to excite the alternator and begin charging. Other diagrams show either a charge indicator light or a 560 ohm resistor in that wire. I used the resistor.
Yea i wired that as well. What could actually be causing this draw? Same thing happened this morning, I had 14 volts to begin with, 6 hours later I was below 2 volts at the battery.
 

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2 volts is crazy low. You should charge the battery and take it to an autoparts store to be load tested. It sounds like a bad battery.

If the battery test okay, try disconnecting only the alternator from the battery to see if it still drains.

The battery should be holding a lot of juice. I would think a draw that large would produce some heat.
 

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Could this be connected to your headlight issue? Were you troubleshooting that and forgot to turn them off? Hopefully just a bad battery, but it would be weird for a battery to be THAT bad.
 

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2 volts is crazy low. You should charge the battery and take it to an autoparts store to be load tested. It sounds like a bad battery.

If the battery test okay, try disconnecting only the alternator from the battery to see if it still drains.

The battery should be holding a lot of juice. I would think a draw that large would produce some heat.

And it does, With a cold car I will use a hand held thermal imager and just scan the alternator and fuse boxes if the current draw is substantial it shows in seconds. It saves a little time.
 

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Will your battery drain if you take the cables off and let it sit or only while connected?
If not, I'm still thinking if all is wired properly then a bad regulator.
 
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