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How to tell if alt. has internal volt reg?

4-pin ECUs use a single element ballast resistor, disregard that part of the diagram in this case.
OK, I got all my parts and will be adding voltage regulator to the system. Since 4-pin I will use existing br.
Thank you all,
I will update...cross fingers.
 
OK, I started to wire up the new electronic vr and have found the green wire at the firewall I thought was the field wire from the alternator is NOT. No continuity with the green tab on the alternator. I cannot yet find where the green field wire from alternator actually goes. It is part of a large wiring bundle. I hate to have to unbundle all those wires. Where would it go since there is no vr to go to?
I have an eye appointment later today so more work will have to wait. Once eyes are back to normal I will see if field wire is grounding out in the bundle. Any other ideas on what to check?
Your suggestions are welcome.
 
Latest update:
Green wire from alt. goes to ground.
Blue wire from alt. goes to ground also.
Anyone explain why? Are these just to ground the alternator to the chassis? Would that mean this is a one wire alternator with no need for a voltage regulator?
I am leery of connecting new electronic alt. to these leads until I understand.
 
Do you have a alternator shop near you? I guess I would take it in and find out exactly what you have. They could put it on their machine to check it out as well.
 
Your posted pictures clearly show fully insulated field brush assemblies, insulators are clearly visible. No indication of any other connections to them other than the pictured green and blue wires. If both leads are in fact grounded there will be no alternator output at all. As fare as I know PowerMaster’s Chrysler “one-wire” reproduction is the only “square-back” reproduction with a true internally mounted regulator, still has a lead exiting the case to connect to a field brush, the other brush would be grounded through it mounting screw and clipped off to prevent external connections. The info/diagram on how to make that/your externally regulated Tuff Stuff alternator work correctly has already been posted.
Powermaster alt.jpg
 
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I'm a little out of my league here. Having only ever put external regulated alternators on Chrysler products.
If it is truly a isolated field alternator, a way to check if it works is, put battery voltage to one tab and ground the other and it should full field/ max output. Do not run it like this for very long it will cause a open in rotor winding.
If a isolated field is grounded and the other is to battery voltage it will drain the battery. Current is flowing though the rotor winding to ground.
A isolated field alternator with the flat pack 1970 up voltage regulator shuts off all electric (battery and ground, hence isolated) to field when ignition is off, no drain.
A 1969 and earlier non isolated field (one side is always grounded) the voltage regulator opens when the ignition is turned off, no drain.
I do not see the little added voltage regulator shown in ad picture.
From what I know of Chrysler alternators those blue and green wires are the brushes. They provide small amounts of current to make the rotor have a magnetic field. This magnetic field spins with the rotor crossing all the winding wire you see looking through the fins in the case. This causes the electrons to move or have energy in a direction all this causes a current/electron flow or amperage (ohms law for the technical jargon), providing electricity to the battery and everything else.
I do not see how they would power those brushes with them connected to nothing so the little add on vr makes sense. I think yours is missing and could be replaced with a normal Chrysler VR, either will work.
Hope this makes sense I'm kinda rambling as it pops in my head. Don't be afraid to question it, Grammer is not my strong suit.
You really need to know what alternator you have, which of course was your original question so I'm not much help with that.
 
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Clearly I need to know what kind of alternator I have so I will seek out a local shop that knows these things before I go and ruin an alternator or fry wires.
 
Are you sure its the alternator that's draining you battery? Look up how to find a parasitic draw on your car?
 
If you unhook all the wires from the alternator and then with the positive cable unhooked from bat put a test light (not a voltmeter) from pos cable to bat and if it lights there is a draw on the bat. If no draw hook the wires back to alt and try again. If light comes on something inside alt is drawing power
 
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