63 Fuelie stumbles off idle

[Troy P.]

Re: 63 Fuelie stumbles off idle

Oh I forgot to say the fuel was from last summer with Stabil added. But I put a half a tank of fresh 91 in today with no change in drivability. I'll add some
Chevron fuel injector cleaner at your suggestion.

Coil is a Delco which was new 22 years ago when I restored the car. Now maybe 4000-5000 miles of driving since then.

Since the car ran fine during half my outing yesterday what is most likely to have gone wrong while driving? Anything in particular or everything you listed, John.

[Jim L.]

Re: 63 Fuelie stumbles off idle

Troy, does the engine run OK and make good power after you get beyond the stumble?

Jim

[Troy P.]

Re: 63 Fuelie stumbles off idle

I believe it is smoother but not quite normal.

The stumble occurs even if accelerating slowly so the enrichment valve does not kick in.

Seems odd that it should idle so well.

[Carmen R.]

Re: 63 Fuelie stumbles off idle

What model of Pertronix do you have? I've had trouble with their first version and had the same symptons your having with the same engine. If you have a timing light check each wire for spark. You might not be firing on all 8.

[Troy P.]

Re: 63 Fuelie stumbles off idle

Not sure what model it is but I put it in in 1996. I suspect an early model. I'll do the test you recommended.

Stumble smooths out at high RPM. Its the mid range where the problem is.

Meanwhile I've found: main diaphram, cranking signal valve, air filter, fuel pump cable, vent tube, enrichment diaphram all OK. In addition it seems to me that the enrichment operation is normal, but I may not understand that fully. The rubber tubes that connect the piping under the unit look OK as best I can see.


I took the choke apart to see if the piston was sticking and found there is no piston. Is that normal for a fuelie? In any case the car used to run fine without it.

Could it be the spill valve?? I hope not because it looks like you have to take the whole unit off, or at least the fuel meter if one can reach all the fastners, to get to it.

[Troy P.]

Re: 63 Fuelie stumbles off idle

As you may know 85% of fuel problems are really electrical.

Well no juice to plug 3 and 6. Gotta be the problem. Now I need to investigate why. Pertronix most likely.

Pull distributor and redo.

Did you switch back to points and condensor or did you go with an updated Pertronix? If the latter, are you happy with it?

[Dan D.]

Re: 63 Fuelie stumbles off idle

Cylinders 3 and 6 are next to each other in the firing order. Could be arcing in the cap between these two. -DAn-

[Carmen R.]

Re: 63 Fuelie stumbles off idle

Troy:

It's definitely the Pertronix. I had the same exact problem. There's an article in the Ontario Chapter news letter "The Spinner" covering this problem. I'll try to forward with pictures. Please have patience. Not too good with compiuters.

Carmen

[Loren L.]

Re: 63 Fuelie stumbles off idle

And the plugs weren't fouled?

[Carmen R.]

Re: 63 Fuelie stumbles off idle

Ontario Chapter Newsletter_2013

Not sure if this will work.

[Carmen R.]

Re: 63 Fuelie stumbles off idle

Ok, it didn't work. Can't get used to these things.017.jpg

How about this. Boy I sure need a course on computers. Be careful when you remove this ring. You don't want to loose those little magnets. Ask me how I know.

Carmen

[Troy P.]

Re: 63 Fuelie stumbles off idle

All the plugs were pretty heavy with soot because the plugs were so cold - AC43s. 3 and 6 didn't look different than the rest.

[Troy P.]

Re: 63 Fuelie stumbles off idle

Didn't get the article. Can you email it to me instead? troy.pyles@comcast.net

[Troy P.]

Re: 63 Fuelie stumbles off idle

I noticed that they were next to one another and wondered if there was a connection.

[Carmen R.]

Re: 63 Fuelie stumbles off idle

#3 & 6 on mine were real clean, because they weren't firing and the fuel gave them a good bath.