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Repairing a Bad Generator Armature

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  • Repairing a Bad Generator Armature

    I was sent an armature to repair some wires that got scraped away. I've never seen this happen before and wonder just what rubbed so long that it wore away some of the wires leading to the commutator. It must have been the field wire or power brush to stud wire. I had to splice in some short lengths of solid copper wire after I scraped away the lacquer coating. I also had to turn the damaged taper where someone had pressed or hammered against the front end. With the damage the pulley wouldn't mount correctly. A longer bolt should always be run to the bottom of the threads to press against, or tap with a hammer.

    After the wire repairs I tested it on my growler, and once it passed that test I polished the commutator, repaired the taper, then sprayed the front end with clear shellac, and used Loctite slow set clear epoxy to hold the commutator wires in place. It should be set up enough by tomorrow to mail it back to the owner.

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  • #2
    Hey Tom, nice work, you plan on any balancing?
    You wana look waaay far up da road and plan yer route because the brakes are far more of a suggestion than a command!


    • #3
      I've never seen any evidence of factory balancing on armatures, so I think it will be ok, although I wondered about the same thing.
      At 2000 engine rpm the armature will be turning 3000 rpm.


      • DaWizard
        DaWizard commented
        Editing a comment
        Yes, that is not quite enough to throw off the solder, but it is enough to set up some strange vibrations. If you are able to check the balance, it could be worth the shot.

      • Mitch
        Mitch commented
        Editing a comment
        Nice post Tom, I added it to your other Genny thread in the chassis tech forum.

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