Thoughts on my stumbling

[63Futura]

I am hoping that someone can help me here. My '63 Falcon with the 170, Ford-o-Matic, AzCoupe headers, and a Pertronix box sometimes likes to act up on me. Not all the time though. Here is the situation:
Sometimes (Any weather condition), the car will begin to stumble and sputter like it is missing on some cylinders. I won't do it at other times. For example, on Wednesday I drove the car in to the office. Ran beautifully all the way over here. I stert it up to go home, and it starts to stumble on me. I had to pull the choke out to increase the RPMs to keep it running. The car also wants to stall on me when I go to pull away from a stop sign or light.
It had been doing this to me prior to the installation of the Pertronix module, and I thought that the installation of the box had cleared it up, but I was wrong. The car has got what I seem to recall is a Holly 1949 single barrel carb in it. I can't really think of any reason that it should be doing this. My mechanic said that he can't find anything, and it won't act up when he has the car.
Can anyone relate that they have had the same problem, and if so, what the cause was? Or, can anyone give me any ideas on what my mechanic should look at? Maybe there is some dirt or something floating around in my carb, and it occasionally plugs something up???
Any assistance is greatly appreciated. Thank you.

 

[LaGrasta]

Yeah, I agree with your original thought, the carb. I'd clean out the float bowl and clean or replace the fuel filter. See what happens. Those are both cheap and easy. More often than not, it's something simple.

 

[Anonymous]

Does it only happen after the car has been warmed up?
It could be fuel delivery, check the fuel pump, filter, float bowl and check for vacuum leaks (edit) around the carb spacer.
It could also be timing, check with a timing light and the vacuum advance disconnected and plugged. Check the vacuum advance diaphragm, check the tube for adequate vacuum and check it for leaks.
Edit: When was the last time you put in a new set of spark plugs?

 

[63Futura]

Ragtop,
Not just when the car has warmed up. The car stalled on me just after I had pulled out of my office's garage. At that moment, I had thought I hadn't warmed it up enough. Then, when I got off the freeway (about a 15 minute drive) it hardly wanted to stay running. I decided to take the easier way home so that I didn't have to go up any steep hills once I got off the freeway.
The thing that puzzles me, is that it doesn't seem to act up at all when I am driving the car (ie: cruising). I mainly notice it when I am stopped at idle, and just starting to take off. As I start to apply the gas, it acts like it wants to stall just at that instant. If I give it too much gas at that time, I think it will stall.
To answer your other question, I am not sure about the plugs. I can't really remember, but it has probably been a couple of years.
The vacuum advance diaphram was replaced less than 6 months ago.
I also know that my mechanic (who is very familiar with Fords/Falcons and i6 engines) timed the engine when he installed the Pertronix.
I am just at a loss over this one. I would like to be able to drive the car more, but just don't want to get stranded anywhere.

Thank you both for your suggestions. They are kind of along the same idea as to what I was thinking of myself. The confusing thing about it for me is how inconsistent it does it to me.

 

[Anonymous]

I had the same symptoms once, it was a vacuum leak. Do everything we discussed above including checking the nuts that hold the carb and spacer to the log. You can also spray some carburetor cleaner around the base of the carb to see if you have a leak. Also, it wouldn't hurt to put a new set of plugs in. I like the Bosh Platinums, that and a fresh set of plug wires should complement your new Pertronix module.

Did you replace the coil when you had the Pertronix module installed? Also, did your mechanic know to remove the ballast resistor? It is located under the dash in the red line between the switch and the firewall. It will take the form of a small rectangular box (usually white) or a resistor wire in the line. It is easy to spot.

 

[61Futura]

I am having the same or similar problem right now. It started when my home made gasket on the fuel bowl started disolving. It was really bad until I cleaned the fuel bowl and jet. Now it just misses when cold like when you have the idle mixture set to low. I tore the carb all apart and sprayed carb cleaner thru all the little passages and put it back together again. Still acts the same. When I hook the timing light to the coil wire, I could swear I can see the miss in the light. I put new points, condenser, and a different coil on. I checked the resistance of all my plug wires. Still doesn't like running cold at idle. It runs smooth when you give it some gas and has no hesitation. Once it is warm, it barely misses. It used to run so nice. It is driving me crazy. I was going to tear down the carb and soak it overnight and use an air hose to blow out the idle mixture passages next. I think I already tried plugging the vacuum line to the pump for my wipers, but I'll have to try that again first.

 

[Asa]

now that suggestions have been made on what to do...

first thought upon reading this:

pick up your feet

*wanders off in yet another medicated daze*
*walks into wall*

 

[addo]

63's problem sounds a bit like the accelerator pump not working properly.