short in distributor keeps reappearing - any ideas?

[Fred K-OR]

Another thing to check may be your points-are they in good shape?

Just a thought again.

[mleder]

Would you happen to have a different lower plate that you can swap out for a test run?. When the plate goes bad the tab on the bottom will show continuity to the main part of the plate. The insulating washers that the rivits pass thru may be old or on the intermitant part of being good/bad.When pressure from the ingnition cable or even reassembly into the distributor body or vibration from engine running might possibily cause the the plate to go to ground. This condition may only happen possibly when you've gotten everything togather. This could disapear when you remove part of the assembly or move it to the bench for inspection and testing. You would not be able to determine by a visual check of the rivits or washers if this odd thing were happening. A long shot but one more thing to consider.

[jmeckel]

All kinds of ideas listed so far, and all good ones to!. So to add some "out of the normal" problems I have seen on coil type ing. issues. One thing to try, is watch the coil, and dist in the dark, you maybe surprised to see sparks at places you never thought. I have found both coil and dist cover problems this way. The smallest carbon path in the wrong place can cause all kinds of problems. I posted it before but now I found a picture to add, take a good look at the copper strap on the points, I am here to tell you I spent hours working on a dist "shorting out" problem, no matter what I did it would start to work and then fail, it was all caused by the point strap that would touch the case whenever it felt like for just as long as it felt like. It about drove me crazy (maybe a short trip to crazy anyway!).

Model a points.jpg