When you did the Pertronix conversion, did you run a new +12V line to it? They need a full 12 volts, and the original wiring harness has a resistive wire in it going to the coil. The resistive wire serves the same purpose as the old ballast resistors on the firewall.
- Slop in the timing set should be obvious when you put a timing light on it. (The mark will "walk" noticeably.)
- I am not a fan of ignition conversions... though many persons like and recommend them, many others have problems and complaints about Petronix products. (Only GM's HEI is a true H.E.I. in this context.) Having said that, a conversion is only as good as the components it's mated with. Check the condition of everything and follow Petronix instructions to the letter, including coil resistance, which is critical...
- Assuming you have an otherwise healthy engine, most carburetor problems are ignition related.
When you did the Pertronix conversion, did you run a new +12V line to it? They need a full 12 volts, and the original wiring harness has a resistive wire in it going to the coil. The resistive wire serves the same purpose as the old ballast resistors on the firewall.
Wow,
That was not in the instructions.
It did run fine after the conversion.
I am tempted now to put the points back in to see if that solves the problem.
I am using the pertronix coil but I kept all the old parts.
Trying to figure this out myself first because of what Covid-19 has done to my job,
As mentioned full 12V is important for the Pertronix to work properly. Any slop in the distributor shaft? Is your float level set correctly in the carb?
When you did the Pertronix conversion, did you run a new +12V line to it? They need a full 12 volts, and the original wiring harness has a resistive wire in it going to the coil. The resistive wire serves the same purpose as the old ballast resistors on the firewall.
Wow,
That was not in the instructions.
It did run fine after the conversion.
I am tempted now to put the points back in to see if that solves the problem.
I am using the pertronix coil but I kept all the old parts.
Trying to figure this out myself first because of what Covid-19 has done to my job,
I have lots of time to play.
Was just looking at the Pertonix instructions online. The requirement for +12v is in the Wiring Instructions on page 2, including Recommended Installation which addresses bypassing the resistive wire.
Was just looking at the Pertonix instructions online. The requirement for +12v is in the Wiring Instructions on page 2, including Recommended Installation which addresses bypassing the resistive wire.
Before I'd be worried about tearing in to the engine for an almost indiscernible shutter, I`d be looking at the ignition wires and making sure there is good contact at coil and plugs, look for cracks and arcing, are the boots good and not soft and cracked or melted. After that I'd be going at that carb, make sure its clean and then set the idle mixture properly followed by curb idle. How about your fuel filter, I mean these are all easy things that cost little or nothing make your baseline right but they eliminate a lot of things too. If you don't trust your timing light its gotta be timed after Petronix switch.
I keep a spray bottle in my garage for ignition misses, have a look:
I know this may be a dumb (obvious) solution but did you check the gap on all the plugs when you installed them?
0.035 Gap
The plugs I took out were gapped the same.
Tiny said he would have to have it for a day.
He would start with a compression test.
and go from there.
I am not saying that this will fix your problem but with Pertronix you can run 040 to 045 on your plugs. A wider gap is better with that amazing conversion. I have had Pertronix on all my oldies for over 20 years and swear by it. Never and i mean never had any issues at all with that wonderful system. Good luck fixing your situation there.
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1957 Pontiac Pathfinder Deluxe sedan restored 261 six
1974 Chevrolet Caprice Estate wagon low mileage original 400 V-8
Did your engine have this issue before the conversion? If not you should be able to rule out everything other than what you swapped. Give the tech working on it as much information as you can to help him with the diagnostics and save him some time.
Did your engine have this issue before the conversion? If not you should be able to rule out everything other than what you swapped. Give the tech working on it as much information as you can to help him with the diagnostics and save him some time.
Good luck.
I did the conversion last fall and everything was great.
Sat for 5 months in a body shop with me having the motor out for a few weeks.
It has never really ran right since I got it back.
First dirt in the fuel filter and then a piece of something stuck in the needle.