[Spridgets] Pertronix failure now understood.

[Dean Hedin]

I guess it was inevitable.  My Pertronix failed.

But I figured out how it failed and I have a workaround.

Let me first explain the symptoms.  
I converted my Bugeye to an alternator several years ago.  In doing this I had to transfer the guts of an
electric tach into the origianl Bugeye mechanical tach.  This all worked fine, even with the Pertronix.

In the course of getting my car back on the road recently I've been experiencing some hesitation issues.
In addition, the electric tach stopped working.  It was intermitent at first then quit completely.

While troubleshooting the hesitation, I decided to disconnect the electric tach wire from the coil so 
as to eliminate it from the equation.

After doing so the car would not start.  Very strange.  Disconnecting the tach wire should not have killed things.

Here is what happened.  The condensor inside the Pertronix module failed.  The input capacitance of the line into the tach
is what was allowing my car to run.  Disconnecting that wire, no more capacitance and no spark.

The tach died because the lack of a real condensor caused a high flyback voltage to the tach input.
I'll have to pull the tach out and see if I can fix it.

To get the Pertronix working again, I just connected a 0.22uf 250v capacitor from the negative lead of the coil to chassis ground.

I'm not sure this is how other Pertronix units have failed but anyone else who has a failed Pertronix might want to try this fix.

What killed the capacitor inside the Pertronix?  Not sure.  I carefully photographed all my wires before I disassembled things 
last year and used these as a guide for reassembly.  I think it was just age that killed it.

My hesitation issue turned out to be carb related.   

I will drive the car with this fix until I finish building this unit:  http://www.molla.org/DIY-CDI/SC-DIY-CDI-article-hires.pdf