PerTronix question

[Lenz]

Anyone ever had one of these do a partial fail or is it usually a total fail?  The 300 in my F100 picked up a random misfire from idle up through cruise, most notably at slow speed.  Have 150 +/- 1 PSI on a dry compression test, but notice that #1 runs over 100F cooler at idle.  Intake/exhaust gasket replaced, vacuum is a little low but steady at 15.  Advancing timing improves vacuum but increases problem, set right now at 8 before.  Wires, cap and coil are all new points style parts as I believe they should be when running the Ignitor.   I have a 12 volt supply to the Ignitor and 10.5 resisted to the coil, again as I believe it should be.  Other than installing a proper FE, any thoughts

[chris401]

Anyone ever had one of these do a partial fail or is it usually a total fail?  The 300 in my F100 picked up a random misfire from idle up through cruise, most notably at slow speed.  Have 150 +/- 1 PSI on a dry compression test, but notice that #1 runs over 100F cooler at idle.  Intake/exhaust gasket replaced, vacuum is a little low but steady at 15.  Advancing timing improves vacuum but increases problem, set right now at 8 before.  Wires, cap and coil are all new points style parts as I believe they should be when running the Ignitor.   I have a 12 volt supply to the Ignitor and 10.5 resisted to the coil, again as I believe it should be.  Other than installing a proper FE, any thoughts

Pull your compression gague Schrader valve and do a running compression test. You could have a sticking valve causing it to close slower while running. Your 300's running compression should be in the 25 to 30 psi range.

[jayb]

A partial fail of electronic components is completely possible, I don't run Pertronix stuff but I have had that happen with MSD distributors and Ford distributors, and also with one crank trigger sensor.  Try ruling out the other stuff first (coil, plug wires, etc.), and make sure your wiring is solid, but if the problem persists, it certainly could be the Pertronix.

[cjshaker]

I'm to the point (pun intended ) that if you run an electronic ignition, I highly suggest that you keep a spare in your car/truck, along with the basic tools to change it out. I've had random misfires with electronic ignitions, and it's almost always related to the pick-up. And it's always been a precursor to a total failure. I've got a few friends that run Pertronix, and one of them had the erratic misfire that you mentioned, due to the pick-up. I've had it happen to me 3 times now, but on MSD pick-ups. I'll never be without a spare again.

[Lenz]

Thanks gents.  I'm going to do the running compression test to verify valve operation and get a backup ignitor.  Even if the current one isn't the problem I like the idea of carrying a spare for that eventuality.  It would be pointless to wait for a fail anyway, I will admit to losing faith in the quality of electrical components currently available to the general public. 

[BattlestarGalactic]

After nearly 20 yrs I finally put a unilite in my black car.  Runs better now then ever since there is no point bounce at 4000 rpm.  I'd keep an extra one in the glove box........but you have to jack the blower up about 6" to get the cap off so replacing it "on the fly" isn't really that easy.   

I just hope the fact I run it with a 6AL box will help eliminate any over current situations.

[428 GALAXIE]

I'm sure this ain't the case with your current issue but want to share the problem I had.
I had pertronix 3 in original Ford distributor and it worked fine but is so worn out so ordered new one from ROCKAUTO.
Later but the new dist in with pertronix start the engine fiddle with timing but idle has even mis to it.
Went to test drive still occasionall missfire and sluggish from bottom(too fast curve?).
Well putted old dist back with pertronix and works fine.
Looked the new re pop distributor later only thing that I found was the points cam ground so much uneven and out of center that pertronix didn't "read the cam on every rotation.
This is only speculation at this point but made this reluctor? Wheel to displace the points cam.
[imhttps://drive.google.com/file/d/1QsTtmNnQ_YTL3ndB0VzALz-u77Ywdv6s/view?usp=drivesdk

[427Fastback]

I have never purchased Pertronix stuff as I have never had anything (customer supplied) last more than a few days..I refuse to use the stuff.Since the mid 80's I have used Ford Duraspark on everything that is for the street.This includes my 427 and the 300I6 in my 1936 Diamond T..I know failures happen but I have yet to have one.Having some spare parts is not a bad thing.I also only use genuine Ford distributer parts and boxes....JMO....Cory

[Nightmist66]

I've had the II and III, both saw 7k once or twice. Never an issue. Factory dist. without vac. advance. I am working on a whole new setup with the Ignitor III, HC 60k coil, and the new digital HP ignition box. Hope it works. I like the stuff, myself.

[RJP]

I'm also a fan of Pertronics. I have 6 basic "Igniter I" currently in service and over app. 30 years I've had only one fail. When it failed it seem to produce a weaker spark noticeable at heavy load/freeway speed and got progressively worse until all it could do is allow the engine to idle. Took it out and returned it to the store where I bought it and they exchanged it no questions asked. I do carry a set of points/condenser prewired to hook up to the coil and ground if another Igniter fails....Better to have and not need than to need and not have.

[Lenz]

Well, it was the ignitor.  Since it started to hiccup last fall I'd say it only lasted about 7,000 miles   I went through my "what the hell is all of this crap and why didn't dad throw it away while he was alive" box and retrieved the points and condenser that were in the  truck when I bought it.  They are now in the glove box.  If the new ignitor fails I'll throw in the points to keep me moving and go another route.