Stalling problem

[MXmaniac]

My '69 C-20 has a 292 I6 and when I come to a stop at a stop sign or light the rpms slow way down, and if I stop hard enough it will stall. It must not be getting fuel, right? Could the problem be my float level? Or the fuel pump? Any ideas?

[72 cheyenne pdx]

Does it start right back up with ease?

[ChevLoRay]

This one brings up my past problem. Whether or not it has anything to do wity yours is purely conjecture.

I also had a problem when I let off of the gas on my truck. It would die. I could restart it, drop it back into gear and go....until the day it didn't do squat. At a traffic light. On New Year's Day. With a woman behind me who had a horn and wasn't afraid to use it. Another story.

Anyway, the problem was the wire to the reluctor in my HEI had an intermittent break in it. The operation of the vacuum advance, which your distributor should have, caused the intermittent break to occur. May not be a problem if you are still running points, but in case you aren't, it's somewhere to look. Still, and hopefully, it will be a "horse" of a problem, not a zebra.

[2bits]

If it drives ok, but just dies when you come to a stop, I wouldn't think it was fuel flow because it takes more gas to drive than it does to idle. If it was the float or fuel pump I would think that it would get worse as you drove and better at idle. That's not always the case, but generally speaking

I would check for a broken or disconnected vacuum line, spray WD-40 around the base of the carb to see if it is sucking air there too. Could be the choke plate is closing up too if that vaccum line is leaking, or the diaphram is bad that holds it open (if you have one). Timing could be off too.

[cdowns]

id be checking the fuelfilter and air filter first the lower the rpm the less pressure from the pump if a part clogged fuel filter its starving at lower rpms

[68gmsee]

I'll go with vacuum also. Sucking too much air and not enough gas at idle.

Could be wrong, but, that would be my guess since it's happened to me. If I remember correctly, mine had to do with brake booster.

[MXmaniac]

Well I have a manual choke, and when it dies I have to choke it all the way to get it to start. If I have to come to a hard stop I just choke it enough to get it on the fast idle and that keeps it from stalling. I know the fuel filter and air filter are ok, they aren't old at all. First thing I'm going to do is put new valve seals in tomorrow. I think that could be a part of the problem, that should eliminate the possibility of a vacuum leak at the valve seals. I don't think there can be an air leak anywhere else, not long ago I replaced the intake/exhaust manifold gasket, as well as the gasket under the carb. The distributer is new with a Pertronix kit, and I know the vacuum line is good. So I will try valve seals and see if that helps.

[68gmsee]

MXmaniac, I'd try the easy things first... A vacuum leak should be fairly easy to diagnose, but, if you pretty much have determined that it is not a vacuum leak, and/or fuel filter, then, the next obvious thing is fuel delivery.

This was already mentioned above, but fuel pump not pumping enough gas would be the next thing to check. That would be easy enought to check also.

And then, I would go with checking the carburetor again before going with the valve seals. I've had bad seals on mine and never caused the symptom you are describing..

[chvtrkman]

When I couldn't get my 292 to stay runnnig earlier this year it was because I had the timing set wrong....and I had a vacuum leak.I changed the the intake/exhaust manifold gasket and I'm not 100% sure the timing is right on, but at least it stays running now.

[2bits]

My previous engine wouldn't idle smooth to save it's life and would want to die at stop lights too, but I had a definite miss that turned out to be the #2 piston ring. I am (hoping) assuming your engine runs smooth otherwise, and you don't have this deep of a problem.

Having to choke it all tghe way to get it to start back up "sounds" like it would be not enough fuel OR too much air. Good luck on the valve seals!

[MXmaniac]

OK well I replaced the valve seals. The original seals were o-ring type seals, and the replacements were an umbrella type. So I changed them out and there was no difference what-so-ever in how the motor runs, nor the slight bit of white smoke out the tailpipe, nor the oil consumption. A few days ago I found out the umbrella seals are meant to be used WITH the o-ring seals, I didn't know this and I assumed that the replacement seals would replace the o-rings. I haven't put o-ring seals in it yet. Yesterday I raised the float level and that made no difference either. Exact same as it was before. Now I'm thinking that the problem may be in the vacuum advance. So I am going to try plugging the vacuum line, adjusting the timing by ear, and seeing how it runs with the line plugged. Anybody else have any ideas? I'm almost out...