no juice to coil

Good morning all:
all of the rotors I have are all the same and I have never had this issue before, ever. As I mentioned, this disto is a Prestolite that I converted to Pertronix over 20 years ago. The inside of the disto cap shows no damage at all (or none that I can see). is it possible that there is too much gap? or maybe too much voltage? Another question: with the Scout running (and stock coil), I am wondering how to measure the amount of voltage coming from the positive post of the coil. I had swapped out the old coil because of what I thought was a bad coil (earlier in the post). I will run this Pertronix II for this week and post the results.
Excuse my shortness of explanation/knowledge on this as I am not an electrician and these kinds of issues really get me freaked out as I do not want to damage the disto, rotor, coil, cap, but more importantly the new Prestolite II I just installed.

Thanks,

Richard
 
The voltage primary voltage in 12v nominal. Secondary voltage will only rise to the amount needed to jump the gap.
 
What is wrong with the rotor that you say has 500 miles on it? It looks normal.
The old one looks like it was ahead of the cap post when it fired. The burning may very well have been from the plastic on that side becoming conductive due to the arcing at the leading edge of the metal piece.
On the resistor, it is intended to help reduce RF interference like resistive plug wires and plugs. If the resistor end has space between it and the metal tabs, it will arc every time a plug fires and slowly burn it self away leaving conductive soot in the plastic .

The firing position on metal tab and the cap post will sweep across the face of the tab and post as the centrifugal advance does it's thing. The variable that could put the two out of phase is the pertronix module sensing location. If it is late or early you'll see the arc witness mark off the middle of the post and metal tab. Drive it for a while and take a look at it again for the arcing location. All caps and rotors will show that and it will show the relative alignment of the two when the ignition fires.
 
good day all and thank you for the replies. I will do the driving and report back.

On to another (similar) issue. My 79 Traveler (with a Pertronix I) is in the garage with a new motor (345, TQ) Prestolite, and Pertronix I. The Traveler is being restored and has not been out of the garage or on the road. It has about 50 hours of running at various speeds just to keep it oiled and stuff while redoing the wiring, interior, bodywork, etc. . New plugs, rotor, disto cap, Accel 8140C coil, MSD 8.5 superconductor plug wires, timed at 12 degrees, vacuum is at 19 steady as well. Out of curiosity from my 77 SII ignition issues, I pulled the disto cap off the 79. If you will look at the attached photo, there is a bunch of what looks like arching residue./dust? I cleaned off the residue/powder (other picture), Traveler starts up just fine.

I've never seen this issue before (the residue) and am wondering what it could possibly be.
 

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To me it looks like plastic ash. What does the rotor look like? All of that white residue is from running in the garage? Looks like a lot to me. But there is a spark at each tower and increasing the energy in the spark that the coil generates will erode things more quickly than on a stock ignition. You will always collect some residue in the cap from under normal driving conditions.
 
yup. all the residue is from running in the garage since January. weird!, I've never had this before in the 40+ years of playing with these IH's. the attached pix of the rotor are from the 79. As I mentioned, when I started the 79 345 in January, everything was new. Does the rotor look like it is making contact on one side only? or is it just me?
one of the concerns that I had was the coil. I am using an Accel 8140C. It's either that or a regular 12-volt coil to use. I do know that they need to have 1.5 ohms resistance and that is what the Accel has. I was worried that "residue" was a result of too much voltage/spark, which was causing the residue. I didn't want to burn out the Pertronix. The other concern that I had was the MSD 8.5 plug wire. According to the Accel website, these are RFI good.

I don't know. Just spitballing. Thanks for the replies all.

Richard
 

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That indicates that your ignition is firing early compared to the rotor and cap alignment. That is not fixable by turning the distributor in the engine like when you set the timing. That can only be fixed by altering the location of the Pertronix module, cap or rotor to correct the phasing..

Look at the white mark on the rotor tip, near the eroded brass electrode, it is being burned by the arc. Guessing that it is sparking a long ways and hitting the plastic. Once it begins the process of burning the plastic, the plastic will become conductive and carbon track.

This is not a ignition power issue. Suggest verifying the parts you have and the Pertronix phasing in the distributor.
 
This is odd, I looked at the Pertronix home page catalog and they do not list a kit for an IH Prestolite distributor. Not sure if that is my error or theirs.
 
As I mentioned, the Pertronix I has been in my 77 Scout since forever with no problems. I am really stumped.
 
My missing the Pertronix was about why I didn't see it on the Pertronix sight, not that I doubted you.
On your issue, you have a rotor phasing problem. IMO :yesnod:
 
ya know, if it's a rotor phasing issue, how on god's green earth do I correct that? Find a shop that does disto work? this is something new to me. There is no "adjustment" that I can see in/on the disto since the two screws holding the Pertronix base is set. The Pertronix module itself is bolted down to the base. Good god!
 
You are seeing the running alignment on your new build. It is burning the very corner of the wiper. That is firing early and with the centrifugal/vacuum advance it gets worse. You should see slight arc witness marks across the entire face of the rotor wiper.

On the magnetic reluctor you add to the distributor while installing the Pertronix, what aligns it to the shaft?
 
on your question re: " alignment", the rotor lines up the reluctor and fits snugly onto the disto shaft. I've looked at the disto shaft and the reluctor to see if there was any looseness or wear, it's all tight. The only movement is when I manually try to turn the rotor, it only goes to the play of the advance springs. Hell, we'll get there.
 
There is a non resistor rotor out there. I don't know the part number.
I say it looks like a rotor phasing issue but I can only use the information I see in your photos.
 
Sometimes, shifting the wires a position on the cap can resolve the issue. I'd time it to 10 deg advanced at idle with no vacuum hoses connected. Then put the damper on the 10 deg mark and mark the edge of the distributor where the rotor is pointing. Then put the cap on and mark the locations of the post on each side with the same sharpie. Remove the cap and compare the marks to see how things are lining up.

Another possibility is the incorrect Vac advance unit is installed. The vac advance rotates the breaker plate where the pertronix is mounted. If the Dizzy was rebuilt, who knows what was put in there.
 
Easy to verify. Grab an old cap, pick a location next to a tower and bore a hole. Probably 3/4 or so. Install and check run it. Should be easy to see if that’s the problem.
 
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