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Pertronix Question - Shave the "Hula" Rotor ?

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Andrew1

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Hi Gang:

This past weekend I installed a Pertronix Ignitor Electronic ignition in my positive ground BJ8. Upon start-up, I noticed that the Distribution cap was doing a little dance resembling a hula hoop wiggle as the rotor goes round inside! Not a stock effect but interesting to watch although.... and it ran!

I took a quick look at the set up, and I gather that the magnetic ring of the Pertronix, when seated, takes about a 1/8th of an inch of clearance off the top of point cam. So, I gather that the rotor must therefore seat 1/8 inch higher than normal.

The solution, sand 1/8th of an inch off the bottom of a stock rotor.... which I did.

The Distributor cap no longer does the Hula dance, and the engine seems to run fine. Can someone comment if they have had a similar experience, or should I have not done that?

- Andrew - /ubbthreads/images/graemlins/canpatriot.GIF
 
My comments come too late as you've already found your own fix for this, but....

It is a routine thing for the magnet ring to be "tight" when obtained from Pertronix. Sometimes they won't even slip over the dizzy cam. It's not unusual to have to place the open end of a suitably sized socket over the top of the magnet ring and "tap" it down using a light hammer. Some people go to the trouble of sanding the bore of the ring a little.

Like I said, it's too late to address your case as you've sanded off the rotor, but are/were you sure the magnet ring was all the way down on the dizzy shaft?
 
Andrew,
I had the same problem when I installed the Pertronix on my 64 BJ8. I used the same solution by lightly sanding the rotor, about 1/16 inch in my case. Like you mine works just fine.
 
All the reported solutions seem to have worked out ok,however, I would like to point out a possible alternate solution.Sometimes rotating the magnet around the cam will locate a spot where it will go all the way down with just moderate hand pressure.I then usually put a dot of white paint on the top of the magnet in line with the rotor notch for future reference.--Fwiw---Keoke
 
Thanks for all the feed back. Yes, I did make sure the magnetic collar was all the way seated using the socket tap method. I suspect that the replacement rotor I am using might have started life a bit thicker than OEM, so the shaving seemed to work.

Thanks again,

Andrew
 
I had exactly the same issue with my BJ8, and also had secured the magnet all the way down but still had lack of clearance. I sanded off just over 1/16 inch from the rotor base and all was well /ubbthreads/images/graemlins/cheers.gif
 
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