[Spridgets] It wasn't the Pertronix after all.

Dean Hedin dlh2001 at comcast.net
Wed Nov 3 19:14:45 MST 2010


So I get my new ignition module off of ebay last weekend.

Pull out the Pertronix and install the new unit.

Still no spark.

So I do the test I did previously, I put a spark plug on the coil directly
and ground the base of the plug with a test lead.  I then manually ground
the trigger wire to the MSD box.  

Plenty of spark.

Re-assemble everything and after some testing I realize that no spark is
making it out of the distributor.

I pull the cap off and take it down to the bench.  I have a spark making
thingy called an Audin coil (it was used back in the 50's to test TV tubes)
I use this to verify the cap and wires are OK.  No spark leakage.

That leaves only one thing. I go up to the car and pull the rotor and take
it down to the bench.

I zap the brass of the rotor with the Audin coil while I hold a screwdriver
(grounded with a test lead) and the spark jumps right through the plastic
to the hole where it fits on the distributor shaft.  I couldn't believe it.

Seems like the powerful MSD eventually ate it's way through the rotor.
The rotor I had in there was an aftermarket one with a rivet used to hold
the brass to the plastic.  Turns out that is a Bad Thing.

A little research on the web and I find this...
http://tinyurl.com/2f3apjb

And I end up ordering this...
http://tinyurl.com/2d3kfjd

I put an old Lucas rotor from the junk box in there for the short term until
I get the new type.

The broken wire in the distributor I had discovered previously was a wild
goose chase. There must have been another sneek path to ground, or the wire
was just barely touching metal.

I guess I ended up paying for my misdiagnosis.  But the way I look at is
that I now have a spare electronic ignition module should the one in there
fail later on. 

Hopefully all my ignition issues can be put to bed for a while.


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