Alternator wire connections

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vintageman

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I installed my engine last weekend and am starting on installing the wiring harness. The alternator I have now is a 40 amp autolite. The harness has 3 wires at the alternator side and 3 wires plus the plug to the voltage regulator. From diagrams and pics on this site, because I have an guages and a tach, I think only 2 wires should be connected to the alternator and the STA should be unplugged. Is this correct? Also, at the other end, pics show a noise reduction capacitor, does anyone have a good source for these? Thanks in advance?

Tom

 

vintageman

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Thanks Don, I appreciate the quick response. I will make sure that I tape the extra wire at the alternator up real good. Appreciate the link to the noise suppressor as well.

Tom

 

midlife

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Something is wrong if you have three positive connections at the alternator and three pins at the voltage regulator (the latter is correct).  The connections at the alternator should be BAT, G(round), and F(ield).  Your third wire may be the Ground wire.  If not, the Stator wire is typically white/black stripe.  If your harness that that wire, then it is the wrong harness for a car with an ammeter.  Someone may have re-wired the voltage regulator to fit the ammeter configuration.

 

Hemikiller

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Here's the actual 73 Ford wiring diagram the techs used. The diagrams in many of the available manuals are missing some very important info, the wire positions on the connectors. You have to parse out the wires that are for ammeter cars, and those that are for warning lamps, as they just put everything on one diagram. 

73_ALTERNATOR.JPG

73regulator.JPG

 
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