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Discussion Starter #1
I have a question about my old pertronix. I have the first model pertronix on my 302. I left the ignition on for 24 plus hours and was wondering if this could be my small backfire. I was wondering if it was a "work or not work" type of electronics or can there be a intermittent problem with these? Also it has had the miss on two different engines and the only thing I havent replaced is the intake and the pertronix. Thank you.
 

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I have a question about my old pertronix. I have the first model pertronix on my 302. I left the ignition on for 24 plus hours and was wondering if this could be my small backfire. I was wondering if it was a "work or not work" type of electronics or can there be a intermittent problem with these? Also it has had the miss on two different engines and the only thing I havent replaced is the intake and the pertronix. Thank you.

When you did the install you tightened down the plate holding the pertronix unit utilizing a shim piece to space the pertronix pick up from the magnetic pick up on the distributor. If you did not locktite the plate down it may have loosend and is now the source of your problem. Watch this vid and locktite the screws. If you dont have the shim piece contact pertronix. I think it might be 60 thou - but i am not sure.

 

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I have a question about my old pertronix. I have the first model pertronix on my 302. I left the ignition on for 24 plus hours and was wondering if this could be my small backfire. I was wondering if it was a "work or not work" type of electronics or can there be a intermittent problem with these? Also it has had the miss on two different engines and the only thing I havent replaced is the intake and the pertronix. Thank you.
Hi,
I have run the original Pertronix igniter for several years without any melt downs. This being stated, there have been reports here and other forums about them "dieing" at different times.
Provide a little more history. Did the backfire start, coinicidentaly after the 24 hr ignition-on marathon? What other changes have you made besides leaving the ignition on? Does the engine start and run, or, just crank and back fire?
The more details, the better the diagnosis.
 

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I have had a few problems with the Pertronix but they all had a common denominator,voltage. When the voltage drops below 9 volts, they just stop working,period. In our early cars there is a pink wire that comes from the ignition switch and goes to the coil. This is a resistance wire that cuts down the voltage. Splice in a regular wire in place of the ignition resistance wire to get full voltage to the Pertronix. As far as the intermittant failures, you are on your own. I have had this problem a couple of times on very long drives but after pulling over with a dead car, it restarted and I had no problems after that. So I was not able to diagnose the problem.
 

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Discussion Starter #5
Thank you for the reply. The backfire did start after I left it on for 24 hours. It starts and runs fine. I actually drove it from here in DFW area to turner falls in Oklahoma. Before I left on the trip I replaced the heads, push rods, rocker arms, distributor, the cap and rotor wires, timing set, and Holley carburetor.....It still does the same miss. I also by passed the wire from ignition to the coil also. It does it when it is under a small load. If you floor it there is no miss sputter or backfire. Weird stuff. Thanks again.
 

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I know it's never good to assume, but I'm assuming you've pulled the plug wires one at a time to see if it's a wire/plug? Also sounds a little like a small vacuum leak. Replaced the hoses when you did all the other work? Might try spraying some brake cleaner around the vacuum hoses to see if it stops. Just my 2 cents, no experience with the Pertronix. It's on the list.
 

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Funny, I just removed the Petronix from my 66. I've run it both, with 12V direct and through the resistor wire. There just seemed to be something funny with it from day 1. It would idle OK then kinda die, like you quickly turned the ignition off & on. It would do this with a regular cycle. Put the points back in and it stopped. Seems a little crisper too with the points and stock coil.

I recently scored a very slightly used Speedway GM style HEI distributer off ebay for $40 that I'm going to put in. Since this style is a high output type of ignition, it needs more power, right? You can't put out more power if you're not putting in more power! So I plan on using the old ignition wire by passing the resistor wire to operate a 12V relay to supply the distributer with a good, low resistance source of power with a larger gauge wire.
 

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Discussion Starter #8
I replaced the wires 4 times now. I was thinking that it could be the intake. That is one thing I havent replaced yet. I checked for vacuum leaks and I couldn't find any. Thank you guys for all the reply's. I guess the next thing to do is try to run points again.
 
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