Register now to get rid of these ads!

Technical Alternator from Hell

Discussion in 'Traditional Hot Rods' started by MikeG5211, Jun 29, 2024.

  1. MikeG5211
    Joined: Jul 7, 2019
    Posts: 65

    MikeG5211
    Member

    Alright so I have this GM one wire alt, I wanna say its about five years old.

    Every once in awhile I would have to re-excite the field winding because it periodically stopped putting out voltage. I did this say maybe 5-10 times since I've had it.

    Well I can't get it to re-excite now, but if I run a 12v wire to the field winding it will put out.

    Now this is where I'm running into more problems, I had hooked the field winding up to the ignition switch but kept blowing ignition switch fuses, sometimes right away, sometimes after going several miles, but she would blow. I tried up to a 30 amp and she blew too.

    Thought maybe between everything on the ignition switch, plus the field winding, it was just too much. So I bought a relay, wired it up so the field winding would be on its own circuit and fuse and activated by the ignition switch, but still even on its own circuit it blew the 20 amp fuse I started off with.

    I checked the field winding for a short to ground and didn't get anything, I'm pretty confused by this whole thing, thought maybe someone could shine some light on the subject.
     
  2. Sounds like my last girlfriend . . . . every once in a while I had to "re-excite" her . . . as she stopped putting out. LOL
     
  3. I think at this point I would just buy another one...
     
  4. Are you talking to Mike or Bored and stroked?

    Ben
     
  5. squirrel
    Joined: Sep 23, 2004
    Posts: 57,961

    squirrel
    ALLIANCE MEMBER

    You have a one wire alternator...but you are doing something with the field....

    I don't understand. Is it a 3 wire alternator? or how did you get to the field winding?
     
    Johnny Gee likes this.
  6. How about some pictures or a drawing of how it’s wired or something to help us help you.
     
    G-son and dirt t like this.
  7. MikeG5211
    Joined: Jul 7, 2019
    Posts: 65

    MikeG5211
    Member

    Alright I think I got it figured out, I opened the alternator up and found a broken wire that goes from the voltage regulator to the bridge rectifier. It didn't look factory, I bought it from Bennett, so either they or their supplier converted it to 1 wire I'm guessing.

    I put in a new wire, put it back together, spun it up with a drill and she puts out again!

    I'm also guessing that broken wire may have been bouncing around inside and periodically grounding out which is probably why I was blowing fuses.
    0630240750.jpg
     
    Last edited: Jun 30, 2024
    1971BB427 likes this.
  8. MikeG5211
    Joined: Jul 7, 2019
    Posts: 65

    MikeG5211
    Member

    My mistake, what I hooked up to was actually the voltage regulator tabs, marked R and F, reference and Field but they're actually bridged together I just learned while taking it apart. 0630240722a.jpg
     
  9. BJR
    Joined: Mar 11, 2005
    Posts: 10,643

    BJR
    Member

    That is one crusty looking alternator. I think I would just buy new one anyway.
     
  10. joel
    Joined: Oct 10, 2009
    Posts: 2,600

    joel
    ALLIANCE MEMBER

    Looks like the regulator terminals are pretty corroded; I'd suggest a new regulator.
     
  11. alchemy
    Joined: Sep 27, 2002
    Posts: 21,658

    alchemy
    Member

    And whatever you were doing to the poor thing to make it that crusty, stop. No electrical components will function in that condition.
     
    Okie Pete likes this.
  12. Please notice the subsequent responses. No, I'm just one of those "practical" types. Thank you for trying to assess my condition and intentions.
     
  13. leon bee
    Joined: Mar 15, 2017
    Posts: 959

    leon bee
    Member

    I think he lives real close to the coast.
     
  14. :D:D. Just yanking your chain! Seems it worked!

    Did not mean any offense.

    I agree on practical.

    Now, back to the original problem with the alternator.:p

    Ben
     
  15. Yes, that "jumper" wire is used in conjunction with certain regulators, to make them one wire alternators.
     
  16. RodStRace
    Joined: Dec 7, 2007
    Posts: 6,166

    RodStRace
    Member

  17. I only use internally regulated alternators.....not one wire. Internally regulated are much more reliable
     
  18. squirrel
    Joined: Sep 23, 2004
    Posts: 57,961

    squirrel
    ALLIANCE MEMBER

    One wire alternators are internally regulated. They just have no external reference.
     
  19. I'd have to try thoroughly cleaning those terminals with some emery cloth, giving them a light coating of dielectric grease and building a new jumper wire with some real weatherproof connectors. Seems like a quick and easy way to verify if that's where the problem is.
     
  20. Kevin Ardinger
    Joined: Aug 31, 2019
    Posts: 929

    Kevin Ardinger
    Member

    Maybe she had blown a fuse as well!
     
    '34 Ratrod likes this.
  21. MikeG5211
    Joined: Jul 7, 2019
    Posts: 65

    MikeG5211
    Member

    She's working pretty good now, I don't see any reason to replace it. its bottom mounted in a T bucket so you know she's gonna get a little wet from time to time. I suppose I could top mount it to negate some puddle splash but either way it still fully exposed to rain. Ill run it til its belly up.
     
    Cooon likes this.
  22. squirrel
    Joined: Sep 23, 2004
    Posts: 57,961

    squirrel
    ALLIANCE MEMBER

    you found the problem, you fixed it, great!
     
    Desoto291Hemi and RodStRace like this.

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.