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So, I parked my GTO in the garage a week ago and came out this morning and it wont start. When the key is turned the starter turns the motor over fast and hard. Carb is getting fuel. Checked for spark, no spark at the Plugs.

The engine is a 67 400, with no points, but a Printronix's HEI set up. Rotor is turning fine, the wires are hooked up correctly from the distributor to the coil. I have12 v from a new battery to the ignition switch.

However, only 4.9 volts at the + post on the coil with the ignition in the run position. When the motor is cranked, The volt meter only reads 9.7 volts at the + post. Then with the coil wire disconnected and my voltmeter stuck in the coil wire it reads as high as 15 volts and jumps as low as 8 volts as the starter turns the engine. Lastly, with a spark plug put in the end of the coil wire there is no spark when the engine is cranked. The coil is new. I am stumped on this one guys.

Now, I am wondering if the ignition switch might be bad? any ideas?

Joe
 

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It was the Printronix unit that puked. I eventually put a full electronic distributor in and drove it for the past year with no issues. I would be careful using these Printronix kits. In the long run it cost me 75.00 for the HEI distributor vs 100.00 for the Printronix change over kit that lasted less than a year, for the reliability and cost factors, go with the HEI distributor.
 

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It was the Printronix unit that puked. I eventually put a full electronic distributor in and drove it for the past year with no issues. I would be careful using these Printronix kits. In the long run it cost me 75.00 for the HEI distributor vs 100.00 for the Printronix change over kit that lasted less than a year, for the reliability and cost factors, go with the HEI distributor.

I did the conversion and had no problems after about 7 years, 25,000 miles of hard running. However, in reading your post, was it really the Pertronix conversion or bad voltage going to the conversion? Improper voltage will burn these things out.

Have you re-tested all your electrical leads as you first did? I get that you installed a new distributor which is of new electronics, BUT if you still do not have the required voltage going to the new distributor or a corroded wire that is not supplying full voltage, you may wind up with the same results - burned out electronic module in the HEI distributor at some point.

The factory used points and the resistor wire going to the coil is used when the key is in the "Run" position so the points don't get burned out. The coil gets 12volts ONLY when cranking the engine to start with a points distributor. This has been covered before in other postings. That said, just trying to save you from a failed distributor if your voltage readings are not as they should be -HEI or electronic type conversions/distributors require 12volts when running. :thumbsup:
 

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Put your points setup back in, If it starts you may have found your problem and your remedy. $10.00 is a small price to pay every 5 years or so. Good luck. Let us know what you find.
 

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Brand new here. Ignition specialist.

There are a few things to know about any and all electronic point replacement systems, such as the PerTronix.

First and foremost, no matter whom says what, no website says differently, no drop-in point replacement system is an HEI, they are a simple points level replacement, and should all always be run with the stock coil and resistor in place.

There are no electronics inside them to "drive" any coil harder than a stock set of points. They make the same output, no matter the coil, no matter the input feed volts, as does a brand new set of points, on their first spark, they just make that all the time,m never degrade.

It was mentioned above that voltage can cause failures in Ignitors, very true, too much input volts, they fail. If the coil has a layer shorting issue inside it, overloads the Ignitor to failure.

Spark plug gaps with Ignitors, no more than .035, preferably .032, and stock GM point coil, run on the stock GM resistor, NO full battery volts. ALWAYS magnetic suppression, spiral or magna core wires, NEVER solid steel or copper plug wires.

First series Ignitor is the best, all from there were "modified" to make them into perf ignitions, doesn't work. The first series is a good system, when the right resisted input volts and other things are done correctly.

Good, clean connections, good, clean grounds are also essential with all ignition systems, battery always grounded to engine first, then chassis.

Just info to consider. YES, I do ignition systems for a living, 40 plus years.
 

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Brand new here. Ignition specialist.
... Just info to consider. YES, I do ignition systems for a living, 40 plus years.
Welcome, Dave. Sounds like you really know your stuff on ignitions so I'd love to hear your opinion: There's a 'certain brand' of spark plug that has been getting some serious hype on all the car shows in recent years, heavy NHRA sponsorship involvement, etc. It has always seemed to me that either a plug gets the fire lit or it doesn't -- that lighting the fire 'better' doesn't make much sense. What's your take on that?
(sorry for hijacking the thread)

Bear
 

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If you are speaking of the "E" plugs, they are utterly useless in a street driven engine.

Another spark plug that is "totally new and ground breaking" is now on all the ads for most parts venues, NO side electrode, only the jacket and porcelain, with a center electrode. These plugs are decades old, and were used in the original Kawasaki H1 500cc triples, with battery CDI systems. They originally came out of the outboard motor industry, and worked fairly well. They used to be offered by NGK as the BUHX, and Champion as UL17V and UL19V, called "Surface Gap". They were replaced with an NGK B9HS conventional negative electrode plug in the 4th year of H1 production, and not used again in a Kawasaki triple, nor any other 2 stroke Kawasaki built. Many have swapped the B9HS into their earlyH1's, they work better.

If you really want ignition system problems, those are the two plugs that will help you along in getting system failures, plenty quick.

This is a one time only note, AND IS ONLY INFO, NOT AN AD. Yes, I am in the ignition system business, have been for decades. I also worked at GM in Skunk Works directly for Duntov, worked on the "Unitized" small coil in cap distributors that just preceded the large diameter, coil in cap HEI's that I helped design and develop at GM. I now do it differently, I designed my own ignition conversions, own, and am the only person at DAVE's small-body HEI's.

I am well versed in ignition system tech, and I do not compromise in answers, you get the truth, period, no BS, and no sugar coating. It is too important to help those that ask for it, with the right info, not over hype ads, nor techs that really don't help. It costs people far too much to do it over and over again, let's get it done right, the first time.
 
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