Charging issues

1975 - 1979 Mopars

  1. 78cordoba

    78cordoba Well-Known Member

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    Ok I got a good ground on the case for sure now but still no change when I try to jump it
     
  2. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    Did a little more digging on your alternator and from the back of the case it does look like the small stud is for a ground wire (I would verify that). The other thing I noticed is that the Field wires are marked F1 and F2. From your pictures it looks like the FLD wire is hooked in correctly. Any chance it is spun 180 degrees. The connector may be a one way style with a release so it can't get hooked up backward. The little ground stud, if that is what it is being used for, there should be a small wire that should go to it (guessing since I can't find a wiring diagram in PDF for the charging system). Not sure if that wire would just ground the case or if it is also a reference signal wire. I will do a little more digging in the AM
    [​IMG]
     
  3. 78cordoba

    78cordoba Well-Known Member

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    Yes I noticed it said grd by it. That's what I had to use to ground the alternator case. It had too much paint on the case it's self and couldn't get it to ground without using the small stud.
     
  4. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    I did find the wiring diagram for a 1976 cordoba but it is not that much help.
    [​IMG]
     
  5. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    The green wire coming out of the voltage regulator (blue connector) runs to the back of the alternator. On the off chance that this wire is broken/melted/messed up you may want to back stab your ground to the green wire at the alternator connection. Just be aware that the two field wires are very close together and you only want the green one grounded to test if increase in RPM will give increase in volts. This will eliminate the 4 or 5 foot of green wire from the circuit.
     
  6. 78cordoba

    78cordoba Well-Known Member

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    I'm not entirely sure which way it should go on? IMG_20200906_121540.jpg
     
  7. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    From the memory on the wires it looks correct. Is the back spade a little bigger than the front?
     
  8. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    For the two spades T1 and T2 that connector clips to; T1 should be from the ing switch and T2 should be the voltage drop sense (the green wire) Problem is I can't find a diagram that shows which is which.
     
  9. 78cordoba

    78cordoba Well-Known Member

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    Yeah the spades are the same size this is how my engine builder had it but he also did a lot of things I had to fix so I'm not sure he had it correct
     
  10. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    Okay, still looking for the correct dang wiring diagram. Sorry that I'm not being much help to you. :(
     
  11. 78cordoba

    78cordoba Well-Known Member

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    No you been very helpful so far really appreciate it
     
  12. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    The electronic one:
    21.gif

    It is an older diagram so not sure about the color codes. I see blue with white trace and I think yours is just blue
     
  13. 78cordoba

    78cordoba Well-Known Member

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    Is there a way to test which spade does what with a multimeter?
     
  14. Builderguy

    Builderguy Builderguy FBBO Gold Member

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    Sorry, I don't know the internals just that one spade will tell the alternator to increase output. Other than that I am flying blind. The parts store may have more info on it.
     
  15. Micah Pohlman

    Micah Pohlman Well-Known Member

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    Yes there should be a ground wire that goes all the way over to the battery. But it also gets bolted to the engine via A/C bracket on its way over there. This might be enough because the 100 amp alt has vibration isolating mounts.
    You can see part of the ground wire just under the heater hoses in this picture. It's the best I can find on my computer right now.

    DSC05072.JPG
     
  16. 78cordoba

    78cordoba Well-Known Member

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    yeah gave this a try still no luck i might have the alternator tested again just to be sure
     
  17. 78cordoba

    78cordoba Well-Known Member

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    would just going to a one wire like a powermaster alternator solve all my problems
     
  18. 78cordoba

    78cordoba Well-Known Member

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    Alternator is working as it should now. I feel like an idiot I think it was the alternator not grounding issue all along. Along with not having a full charge on the battery and the system wouldn't work properly but I'm at like 12.6 with the key off now and like 14 at idle thanks for all your help guys
     
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