Here's what I've done so far:

1. New plugs
2. Swapped carb to another engine....ran/idled fine. Using Holley w/Racing Beat intake manifold.
3. Changed fuel pump
4. capped all vacuum lines
5. Checked float level in carb after stalling....float level good.

Runs, but hard to start. Runs for a while then begins to stall. Will stay running if I pump the accelerator. Running it with open headers.

Help?

 

Search?

 

Will it idle at all?

 

Searched the archives front & back but no help there.

 

Idles for a while then starts to lose RPM and will die unless you bump the accelerator.

 

Does it idle as long as the choke is on? The once it auto's off, die?

If so, it's probably a vacuum leak somewhere even though they lines have been plugged.

You said the float levels looked good after the stall, which it should return to normal as the fuel pump would keep pumping even though none if being drawn from the jets. What do float levels look like while it's stalling?

What PSI are you running on the fuel system? Is it regulated?

 

Yes, when it warms up to operating temp and starts to idle down it dies.
Float level looks good while running. It's a Holley, and the fuel just seeps out of the float inspection screw when removed. When I switched the carb to another car, it worked fine.

Fuel is not regulated. I'm using an external fuel pump to bypass the original setup because the car has been sitting a long time. I had the same problem with the OEM carb & intake so I changed it to the RB manifold & Holley setup. I've checked the manifold for vacuum leaks as best I can and don't find any (no sucking). Hard to check the bottom of the manifold. I'm not losing any coolant from the radiator which tells me the o-ring seals seem to be OK.

I'm stumped. By the way, thanks for the response. "Search" isn't always the answer!

 

What fuel pump, regulator and psi are you running? Are you running a return line?

 

If it's the same pump as on the OEM carb and intake( the aftermarket one your using) and it was doing it on the OEM parts. I'd say it's a fuel delivery problem.

 

Pump is generic. Don't know what PSI. No return line on a Holley. OEM return line is capped

 

Will stay running by bumping the accelerator. Float level is OK when stalling. Don't know the PSI of fuel pump. Guess my next step is a new fuel pump or fuel pressure gauge to determine the PSI. Would low pump pressure make it die even thought it appears to be getting fuel and stays running if you hit the accelerator?

 

Well, right there is where I would start. If the current pump is anywhere near oem, it's not big enough. Knowing psi and and installing an fpr is a must. sounds like the pump is insufficient for the task.