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1972 Ford F100 Alternator/Voltage Regulator wiring

I have a 1972 Ford F100 w/302 engine. The original 6-cyl engine was replaced by the 302 before I bought it. It was re-wired prior to when I obtained the truck. It has never seemed to charge correctly. I don't think it was re-wired correctly. There are no markings on the voltage regulator & this is where I think the problem begins. Currently it is wired like this:
1. From alternator ''Bat'' to battery side of start solenoid
2. From alternator ''Fld'' to 1st position on voltage regulator
3. Nothing connected to ''Sta'' on alternator
4. No ground running from alternator to voltage regulator
5. From the 2nd position on the voltage regulator to start switch
6. From the 3rd position on the voltage regulator to battery side of start solenoid
7. There's a condensor at the voltage regulator that may have been connected to the 3rd position at one time
8. The truck has an ammeter but has been disconnected but seems to me it should have been in the circuit.

Searching the Internet only proved to be confusing - sites contradict each other and wire color code don't match.

I'll greatly appreciate any help you folks can provide.


Renard Sanders

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  • Renard17 Feb 09, 2009

    The truck has never charged correctly, wires are burnt, wires are disconnected. So I'm sure there are some problems.

    It has a new Duralast 61 amp alternator w/o AC. I honestly don't know the rating on the ammeter but it is the stock gauge that came with the truck.


  • Joseph Lukas May 11, 2010

    Renard, before we get into the wiring, why do you think you have a problem?

    BTW the condensor is normally connected to the output wire of the alternator. How many amps is the ammeater? Is it equal or exceed the output of the alternator? what is the make and model of the alternator?

  • Anonymous Mar 22, 2014

    I have a 2006 ford five hundred, put a new alternator in it just last year. It was driving fine, until the other day it wouldn't even start. All of the lights in the dash flicker, until the keys are in the on position, but no turn over. Any help?



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