Another Pertronix Question...

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7173Vert

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For those in the know) Having trouble get my Pertronix II to fire. I’ve tried two new ones, so I know the units  themselves should be ok. I’m using the Pertronix .6 ohm coil. At least I’m trying to use it). I have also tried a factory stock one and an aftermarket unit, still no go. I’ve got voltage signal to the yellow connection at the coil when I put the key in run position. Would the ballast resistor cause my issue? I ran a Pertronix 1 a few years back with no changes to the wiring at all. I’ve heard the P2&3 can be temperamental... Is there any wiring tricks I can try to see if the Pertronix will work? I know I’m missing something, sometimes it just easier to throw it out into internet void... and see what comes back)) 

 
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Two potential problems, the P2 works best with full 12 volts, which means you'll need to either bypass the resistor wire or use Pertonix's relay to pull 12 volts directly from the battery. A 0.6 ohm coil should be used with 12 volts, not with the resistor wire.

 
Two potential problems, the P2 works best with full 12 volts, which means you'll need to either bypass the resistor wire or use Pertonix's relay to pull 12 volts directly from the battery. A 0.6 ohm coil should be used with 12 volts, not with the resistor wire.
I was afraid of that... So the P2 is not recognizing the lower resistive voltage and is the reason it won’t fire, correct? I’m guessing 8v give it take. Is there a test I can do on the car to ignite the P2 and bypass the resistor wire just to make sure it will actually fire, before 👀 ng to eliminate it? I’ll have to looking at my wiring diagrams, I think the resistor wire is under the dash? Curious how some here have ran the full 12v to the coil on these car’s. Thx

 
While I'm no where near an electrical person, on mine, I actually cut the pink wire, removed the pin and soldered in a 10 gauge red wire to the coil. Yes, it is under the dash and not too easy to get at. I'm a smaller guy and still had to take the seat out to work on it.

When my motor was first rebuild in 2012, the guy who put it together installed a Pertronix III and that required a full 12 V through a 10 gauge wire ( I say 10 gauge, without double checking). What I should have done was to just disconnect the pink wire from the plug, leaving it in tact, then add the new wire in its place. The P III is a total pos for a Ford distributor. I now run a PII on full 12 V with the matching coil. Pertronix exchanged the PIII for a PII and coil. Now, just to throw a wrench in, I have a brand new, never used PII that is faulty right out of the box. Unfortunately Pertronix would not exchange it because it had sat on my shelf for over 3 years, so out of warranty. My point, they do have some bad ones right out of the box. There is a test you can do, but it involves using a spare distributor to do a bench test if I recall. You can Google it.

If I were to do it again, I'd just buy the relay to bypass the pink resistor, job done!

EDIT: just found the instructions sheet for the PIII or PII and it requires a 12 gauge wire to bypass the resistor.

 
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The reason some have 12 volts with the resistor wire in place is that the coil isn't 'loaded'. That is, the negative side of the coil isn't grounded through the points or electronic ignition. You can temporarily ground the negative side of the coil with a jumper wire (for a few seconds) and then check the voltage on the positive terminal, as you said, it should be around 8 volts.

To check if voltage is the problem temporarily run a jumper from the battery (positive terminal) to the positive terminal on the coil and try to start it. Do no leave the jumper on for more than a few seconds if the engine is not running.

 
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Guys,

I converted to Duraspark last winter on my 460 and will never look back to points, unilite module failures or others Pertronix issues. The installation was straight forward and I grabbed the 12v feed at the point where the resisitor wire ties into the ignition switch. This way I left the original "resistor wire" in place. I used a small cap recurved distributor from one of the vendors and my motor never ran better.....

Thanks, Jay 

 
While I'm no where near an electrical person, on mine, I actually cut the pink wire, removed the pin and soldered in a 10 gauge red wire to the coil. Yes, it is under the dash and not too easy to get at. I'm a smaller guy and still had to take the seat out to work on it.

When my motor was first rebuild in 2012, the guy who put it together installed a Pertronix III and that required a full 12 V through a 10 gauge wire ( I say 10 gauge, without double checking). What I should have done was to just disconnect the pink wire from the plug, leaving it in tact, then add the new wire in its place. The P III is a total pos for a Ford distributor. I now run a PII on full 12 V with the matching coil. Pertronix exchanged the PIII for a PII and coil. Now, just to throw a wrench in, I have a brand new, never used PII that is faulty right out of the box. Unfortunately Pertronix would not exchange it because it had sat on my shelf for over 3 years, so out of warranty. My point, they do have some bad ones right out of the box. There is a test you can do, but it involves using a spare distributor to do a bench test if I recall. You can Google it.

If I were to do it again, I'd just buy the relay to bypass the pink resistor, job done!

EDIT: just found the instructions sheet for the PIII or PII and it requires a 12 gauge wire to bypass the resistor.
Yes, I have looked at all of this also, trying to come up with the best solution for my car. Adding a relay is not one I will consider at this time, just because I want to hide any changes and keep them to the barest of minimum's... I'm back to points for now... I will look to make up the pigtail that allows me to connect the pink wire and run the power out to the coil, keep it neat and clean, easy to put back to original if need be. I had a Pertronix I on it running the stock coil but it died after a year and very little run time.... I may order another one and see how it goes, for the time being. I like the thought of the PII because of the dwell feature, so we will see. Ive seen a test with the use of a 12V test light and a drill... look's pretty easy to do.

 
Guys,

I converted to Duraspark last winter on my 460 and will never look back to points, unilite module failures or others [SIZE=15.4px]Pertronix issues. The installation was straight forward and I grabbed the 12v feed at the point where the [/SIZE]resistor[SIZE=15.4px] wire ties into the ignition switch. This way I left the original "resistor wire" in place. I used a small cap recurved distributor from one of the vendors and my motor never ran better.....[/SIZE]

Thanks, Jay 
Jay, I have a complete Duraspark set up, brand new in the box on the shelf... As you know, I'm trying to keep the car stock looking. But, I walk by that box every day and say to myself,, "maybe it is time"... I will keep looking at the Pertronix for now. Cheers.

 
Given what you have said, why not just keep the points since they work and you can't make the Pertronix work? Chuck

 
Given what you have said, why not just keep the points since they work and you can't make the Pertronix work? Chuck
Well, what I have said is that I want to convert to Pertronix. As you know... they will provide a better spark overall then the points. I will make them work) But thanks for your thoughts.

 
I THINK the differences are:

P1 - Works with stock wiring, but can burn out if key is left on with engine off.

P2 - Requires 12V feed but has protection against the 'key on' failure.

P3 - Same as P2, added multiple spark and rev limiter.

Having had to deal with the Pertronix devices with my tach movements I am not a fan of Pertronix Ignitors.  Put one on a scope sometime and you will be amazed - voltage swings of 35+ volts at the coil!  I switched over to Duraspark II years ago and love it. My second choice would be points.

 
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I THINK the differences are:

P1 - Works with stock wiring, but can burn out if key is left on with engine off.

P2 - Requires 12V feed but has protection against the 'key on' failure.

P3 - Same as P2, added multiple spark and rev limiter.

Having had to deal with the Pertronix devices with my tach movements I am not a fan of Pertronix Ignitors.  Put one on a scope sometime and you will be amazed - voltage swings of 35+ volts at the coil!  I switched over to Duraspark II years ago and love it. My second choice would be points.
Bob, I've been using an Ignitor II (P2) from before I bought your tach conversion and had zero problems that I know of. I did have an issue with a tach, but that was not related. Since it was replaced, it's been working perfectly and I love it. 

A P3 was installed on my engine when it was rebuilt in 2012 and was nothing but trouble. Not electronically, but mechanically. This of course was the Ford version that has the P3 module mounted on double plates, similar to a stock points setup, but with a cheap plastic bushing thing which wore out in no time. Pertronix replaced it with a P 2 and coil under warranty. I hope by now, they have redesigned that because, other than that issue, it was potentially a really good ignition system.  Regardless, I would not go back to points, but I do want to keep the stock look. 

 
I THINK the differences are:

P1 - Works with stock wiring, but can burn out if key is left on with engine off.

P2 - Requires 12V feed but has protection against the 'key on' failure.

P3 - Same as P2, added multiple spark and rev limiter.

Having had to deal with the Pertronix devices with my tach movements I am not a fan of Pertronix Ignitors.  Put one on a scope sometime and you will be amazed - voltage swings of 35+ volts at the coil!  I switched over to Duraspark II years ago and love it. My second choice would be points.
+1 on What he said. I tried running one many years ago on a fresh build on the dyno. The first full pull was very ragged at the top end. I put a timing light on it and brought the RPM up. At about 5500 RPM the timing was moving +and - 10 degrees from where it should have been. The mechanicals of the Ford distributor were fine. Installed a properly curved MSD distributor and problem solved. 10 degrees too much advance at 6000 RPM at WOT could cause fatal detonation. Chuck

 
+1 on What he said. I tried running one many years ago on a fresh build on the dyno. The first full pull was very ragged at the top end. I put a timing light on it and brought the RPM up. At about 5500 RPM the timing was moving +and - 10 degrees from where it should have been. The mechanicals of the Ford distributor were fine. Installed a properly curved MSD distributor and problem solved. 10 degrees too much advance at 6000 RPM at WOT could cause fatal detonation. Chuck
Chuck, just curious as to your meaning. What module are you referring to? What you are describing is exactly what was seen on my engine with the P3 and the car on a dyno. The timing was floating all over the place. On a distributor machine, the two plates could easily be seen to be moving both inwards and upwards and the timing was moving erratically due to the .030"air gap closing up as vacuum was applied. Cause, the plastic bushing had too much slop in it so a constant air gap could not be maintained. Because of this failure, Pertronix replaced it with a P2 and matching coil, problem solved and never had a timing issue since on a recurved Motorcraft dist. Now, if Pertronix had made the plates bushing similar to that of the Duraspark, I think it would have been a great module for the Ford distributor. Too costly I suspect.

 
What I saw was a Pertronix 1 module. I never bought any other pertronix module after that so I can't speak to P2 or P3 modules. Chuck

 
What I saw was a Pertronix 1 module. I never bought any other pertronix module after that so I can't speak to P2 or P3 modules. Chuck
Thanks for that. I have not used a P 1 either, but as I have mentioned before, I have a P 2 that was faulty right out of the box. Unfortunately I did not find that out until it was out of warranty. Apparently these are all date coded, so they know when they were made. So it would seem that Pertronix do have the occasional bad one. 

 
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