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Distributor body cracks

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  • Distributor body cracks

    I hope this isn't going to be a common occurrence on the latest new distributor bodies, caps, and rotors. Only 1500 miles on this one. Clearance between rotor to distributor body pins .025" on all 4 locations. Now I got to measuring and looking at other things and noticed how the cap looks, notice the carbon (?) in the middle of the cap. It looks shallow like it's burned off a little. And the rotor looks like it's not rubbing on the cap, notice no rub spot and blackened where it should be making contact. So I measured the distance from the top of the distributor body and compared the protrusion of the cap... THEY WEREN'T EVEN TOUCHING!!! Quality parts! There's a photo of the old cap that was on it months ago for comparison. Old cap does not fit new distributor body. New rotor does not fit old distributor body. The old rotor had over .125" gap to the old distributor body, don't know how it ever ran and that was why I changed them. I kept my old parts and now I'm thinking about making them fit and using them. The old rotor has a steel bar instead of a brass bar on the top. Months ago I tried building it up and gave up because I only had a flux core wire feeder. I have a TIG now so it's easily doable.
    Attached Files

  • #2
    Can you bend the rotor spring up enough to touch the cap? If it doesn't touch as it should, then the arcing will eat away the carbon, as you described.

    The rotors I've seen are brass at the tip, so if they are too short you could easily solder a small piece of brass on it to extend it. Just be sure it's also the correct width to match the old end.


    • Mitch
      Mitch commented
      Editing a comment
      I always bend the rotor tang up then put a little white out on it to see if it touches

    • Mitch
      Mitch commented
      Editing a comment
      watch the tig heat does not melt the rotor and loosen the rivet

  • #3
    I have a spare rotor and yes I bent it up. I'm giving that a try for now. The rotor that was in the car when I bought it is steel. But it had a gap of over .125" That was why I bought a new distributor body and rotor. Had to get a new cap to fit the distributor body also as none of the old parts fit any of the new parts. I'm going to TIG the steel rotor to get the gap where it should be so I'll have my spare if needed. Thanks guys!


    • Mitch
      Mitch commented
      Editing a comment
      i never had that issue where the old parts wont interchange with the new.

    • Dennis
      Dennis commented
      Editing a comment
      Yeah I even had a new cap and new rotor that wouldn't fit each other last year. I don't think the material they use for the new distributor bodies is worth a s**t.

  • #4
    That sucks!!


    • #5
      I had a rotor that had no lug on the inside to locate in the slot in the cam. It went around and around when I worked out why the car wouldn't run. It had moved to where it was half way between contacts in the body meaning the spark would jump either way. It sounded like WW3 with all the backfiring. I know I have a good muffler - it didn't split.
      I put that rotor on when I was changing the body because it was suffering the old Model A malady of a cross fire between #s 3 and 4. Shoulda changed one thing at a time, I suppose. Both the body I took off and the rotor I put on were rubbish.


      • #6
        I've seen some of the new distributor bodies that fit loose on the distributor housing, but the ones I bought from Little Dearborn and from Bratton's were a perfect fit. I've never seen a problem with a new rotor, but I haven't bought a new one in many years.


        • Dennis
          Dennis commented
          Editing a comment
          The new ones work as long as the spring tab is bent up like Mitch mentioned in #2.1 But it probably wouldn't cost more than a couple pennies to make that spring in the center 1/4" longer.

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