1972 Chevy Van Alternator problems

1972 CHEVROLET VAN
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BEN TOBIN
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Electrical problem
1972 Chevy Van V8 Two Wheel Drive Automatic

My alternator is not charging my battery and my battery is dead. I jump start with another battery to get the van running, and when I disconnect my battery, the van stops running, telling me that it is also not supplying voltage to the engine. I have checked the alternator while still in the engine at auto zone and they said the alternator is bad.

I then removed the alternator from the engine and again had it checked on Auto Zones machine. This time they told me that the alternator is good! I took the alternator to another place they put it in their machine and they also told me that the alternator is good.

The Alternator that originally came with the van was replaced with the newer model (HAN 7133) that has the voltage regulator built in it when the engine was rebuilt. They left in the old voltage regulator which caused a small drain on the battery. I took out this regulator and that problem went away.

There is +12 volts going into the back of the alternator. Also the two wires that go into the connector that goes into the side of alternator were taken out, and we are not sure which wire goes into each slot. Does anyone know how I can troubleshoot this further for I am at a loss.
Oct 10, 2009 at 8:26 PM
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RASMATAZ
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There is +12 volts going into the back of the alternator. Also the two wires that go into the connector that goes into the side of alternator were taken out

The 2 wire connector is a red and brown wire?
Oct 10, 2009 at 8:42 PM
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BEN TOBIN
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They are blue and yellow wires.
Oct 11, 2009 at 3:09 PM
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RASMATAZ
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One of the 2 that you got goes thru the charge indicator and ignition switch -do a continuity check from this wire to the ignition switch if you locate the right wire hook the other wire to battery voltage
Oct 11, 2009 at 4:11 PM
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BEN TOBIN
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Which connector on the alternator is the one for the ignition switch?
Oct 11, 2009 at 5:08 PM
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RASMATAZ
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Not sure you have a different wires you need to do my last suggestion to find it
Oct 11, 2009 at 5:11 PM