Not sure what ;you are asking its a 1970 plymouth duster 340 which doesn't want to charge
NOT SURE WHAT YOU ARE ASKING
IT IS IMPORTANT to know what we are working with BECAUSE THE SYSTEM CHANGED MATERIALLY in 1970
69 and previous systems had a grounded field alternator with one field terminal, and a completely different VR
70 and later have an isolated (insulated) alternator field and that VR is different from the 69 / earlier types.
You have several possibilities
1...Maybe the charge path (wiring) from the alternator to the battery is open. This is the output wire, goes through the firewall connector, through the ammeter, back out through the firewall, and to the battery +
2..Maybe something in the field circuit is open/ broken, preventing the field from energizing
3...The alternator could be defective
4...The VR could be defective OR NOT GROUNDED
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A...To test the alternator, disconnect the green field wire at the alternator and connect a jumper to ground. Start engine, see if the ammeter indicates a charge as you slowly bring up RPM.
If not, determine if the output circuit is OK. Put your multimeter directly on the alternator output stud (large black wire) and repeat test. If voltage comes way up, way above 16, there is something wrong in that output circuit
If instead the voltage is still low, down near 12V, the alternator MAY be defective.
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B...Now check out the field wiring. If the alternator did not charge in the first test, either the alternator is bad, or the blue field wire/ field circuit is open With key in "run" and the jumper still in place, check voltage "back probe" the blue wire, still connected to the alternator field. If it reads battery voltage, or close, OK
If that voltage is present, and you had no charge, alternator is bad
If no voltage, examine the wiring. Has it been modified?
C....Check other field wiring. Rerun the first check in a different way. This time, remove the blue field wire at the alternator and ground that terminal. Remove VR connector and devise a way (small screws) to jumper across the two wires at the VR connector. REconnect the green field wire at the alternator. Again measure the green wire to ground with your multimeter. It should again show battery voltage. Repeat test, AKA run engine, see if it charges.
If after these checks, with the field wiring jumpered, the alternator does not charge, and if the output stud is still low voltage, the alternator is not charging and is defective.
If the alternator DOES charge, either the VR is bad, not grounded, or the VR connector is loose. Inspect the interior of the terminals with a flashlight for corrosion. "Work" the connector on/ off the VR several times to scrub the terminals and "feel" for tightness. RE-ground VR by scraping paint of rear and around bolt holes, and use star lock washers. VR MUST be grounded.
If alternator charged in tests, replace VR