This is a follow up to an earlier post!
I have a 1969 - 350, with 49,000 miles on it. It has sat in a garage for 16 years and has not been run. This is how I got it! So here is my problem...
When I start the car it runs well for about two minutes then it starts to miss a little than it stalls. When you try to restart it it either won't start unless you hold the choke shut, or it starts and stalls immediately!
Since this started happening I have....
Changed all the filters, rebuilt the carb, installed an electronic ignition module, blown out the fuel lines, changed the plugs, wires, distributor cap, coil, rotor, and vacuum advance. It doesn't matter where my timing is set because it just keeps stalling and when the timing is at 8 deg. tdc, it begins to stall out when you goose the throttle. If you open the throttle while it is running, it speeds up then dies out. I have installed a glass in-line filter so I can watch the flow of fuel and its consistent. I have no idea! Could this be due to a compression issue? Is there some adjustment on the quadrajet carb which I have missed? Has this ever happened to anyone? :confused: :confused: :confused: :confused: :confused: :confused:

 

Or... should I change out my carb for a mechanical one?

 

Do you have a good steady vacuum reading when its running? Sounds like you could be sucking air thru dry rotted hoses or something like that...Do your headlites go up and down? GOOD LUCK........ :eek: :eek:

 

Stale gas? Did you empty the tank and put fressh in?

 

I plugged the vacuum hoses at the manifold just to check that and no luck! :crazy:

 

I have cleaned the lines and tank and have run 3 to 4 tanks through it before this problem began. :smash: :smash: :smash:

 

You say it runs for two minutes then stalls? That's strange -- could it be the fuel pump? Also I can't see why holding the choke down would help. What are your fuel mixture screws turned at? I would turn them in full seat then back off 1 1/2 turns. That's a good starting point.

Simple question -- are you sure that you put the distributor back in correcly? Could be off 1 tooth causing all kinds of problems. Also, check your wire routing. Could be a problem there. I can't see what would cause the car to stall after running for 2 mintues, unless you have somthing clogging the lines. You know, those old sending unit strainers get brittle and could be sending plastic all through your lines. Maybe you need a new sending unit and/or strainer?

Just throwing out ideas..

 

Corellian Corvette mentions checking idle air fuel mixture screws and I concur that that is a good idea. However 1 1/2 turns out from seated is a good place to start with Holley carbs. The carb in question here is a Q-jet. A good starting point for Q-jet is more like 4 to 5 turns out from seated. When I have rebuilt Q-jets in the past I count the # of turns it takes to seat the screws and write it down. Then I put them back in the same place. Dont know why but for me, adjustion idle A/F mixture on a Q-jet is a delicate process. On the Holley cards its a piece of cake. Anyhow, in my opinion, even if the idle mixture is way off, you should still be able to keep it running with your foot on the gas.

 

Look inside the gas tank and you should be able to see the fuel float, you need try it without the gas cap in place, maybe the tank goes into vacuum and stops fuel flow, maybe the fuel suck line gets clogged by junk intermittantly...
collapsing the sock into the line???? combination of jumk in the line...
you could take a 5 gal gas can and run a line into it from fuel pump, and test fire it that way, hell, cap it off out the cans vent, and go for a damn drive even yet....secure it in with rope....

GENE

 

I'd confirm the fuel pump is working. You could be using the gas built up in the fuel bowl at idle. Choke the carb would be drawing as much fuel to the engine as possible.
Be cool
"TEACH"

 

Coil...voltage regulator???

 

I'm pretty sure that I'm getting fuel to the carb (thats why I installed a glass in-line filter right before the carb).

The odd thing is that you can just barely begin to hear it miss about 10 seconds before it stalls. Than you can hear the carb start sucking in a whole bunch of air as the RPM's start to slow quickly, than it stalls as if you shut off the key. If it starts after that , it stalls immediately. I am going insane with this one. But I appreciate any and all help you guys have, and are, offering. :confused: :confused: :confused: :confused:

 

This thing sounds like it is definately running out of fuel. You say you start hearing it miss 10 seconds before it stalls. This indicates it is starting to run lean. Choking it richens it out and allows it to run a little longer. This is definately a fuel problem IMHO. I would pull the tank, pull the sender, flush the tank, look for rust, etc. If you find rust, either refinish the inside of the tank (POR-15 makes a tank coating for the inside of the tank) or replace it.

You only need 3 things to make this thing run.
1. Compression -- you have that or it wouldn't crank in the first place.
2. Spark -- Again, it is firing or it wouldn't crank in the first place. Although I have heard of a coil going bad and once it cools down, it will fire till it gets hot again. This is a possibility but not a probability.
3. Fuel -- I think it is running out of gas. I suspect that something is clogging the fuel pickup. Once you crank the engine, the pump is drawing fuel from the tank. Then trash clogs the pickup. The engine runs long enough to empty the bowl on the carb. It wouldn't empty the fuel line. This is why you are seeing fuel in the glass filter. If there is a clog at the pickup, the pump won't pump the fuel in the line to the carb because of the vacuum formed behind the pump. One thing you might try is to let it run, stall, and then check to see if you have fuel in the carb. Once it stalls and the vacuum between the pump and tank relieves, the trash at the pickup falls away. Once you start cranking the engine again, the pump fills the carb before the pickup clogs again and the cycle starts all over again.

I'm interested to see if I am right on this. I had the same problem with a 55 Chevy. Ended up pulling the tank and replacing it.

dl

 

So you think if there is a vacuum created before the pump than it won't allow the fuel to pass after the pump even though I would be able to see a filter full of fuel directly (two inches) in front of the carb. Is my interpretation correct? Because if this is the case it would make my life somewhat easier (not looking forward to pullling the tank).

Ok, if I were to attach an air compressor to the fuel line just before the pump and blow air back to the tank, how freely should it blow through the line? :rolleyes: :rolleyes:

 

I think it's your fuel system as well. Just because their is fuel in the filter does not mean that the fuel is under pressure. Without fuel pressure, your float bowl will run dry. If the tank is clogged, the flow will simply stop. Your carb does not have the ability to drain the line once the pressure drops.

Check the tank, lines, and fuel pump. You could also install a fuel pressure guage before the carb to see the problem.

-Joe

 

Your interpretation is correct. If there is a vacuum behind the pump, the pump is sucking for fuel but not getting any. If it isn't getting any fuel, it has nothing to pump toward the carb so the fuel in the line between the pump and the carb won't go anywhere. It will stay in the line so you will be able to see it in the filter but won't be moving. Try this experiment: Once the car dies, empty the filter quickly and try to start the car. See if the filter fills back up. If it doesn't, you've found your problem.

As far as blowing back into the tank, you should have fairly free flow into the tank if the cap is off but I wouldn't do this. Blowing through will potentially loosen up more crud in the tank. Dropping the tank isn't too hard on these cars and would be worth the time if this is the problem.

dl

 

My guess is a float problem. The carb sounds like it is delivering a pretty good air/fuel mixture initially. If the floats are sticking, they won't drop down and allow more fuel to fill the bowl. They may not be stuck altogether, but just moving really slowly, so after you wait awhile, they drop down, let the bowl fill, then stick up again. You can get it to turn over and start but not run after it dies because you are putting a shot of fuel into the carb that is stored in the accelerator pump. Hope you find it. :cheers:

 

Make sure your distributor isn't 180 off.
Then, I'd definately heed attention to the gas tank. When it was parked, they probably left some gas in it, and it turned to varnish. The float in the tank is probably sucking it up until it can't pass any more gas through and you loose fuel preasure and dies.
Have you driven it? If so, how's it drive? Does it seem like you're missing a cylinder?
Good luck man,
-Steve :nonod: