[Mashman]

I'm having an issue when starting my car, after it's sat for a few days. But it's a little different than the normal 'need to crank for a long time' issue.

First, I have a 72, with a mechanical fuel pump, with a return line.

When cold starting, I can fully press the accelerator pedal, and slowly release (like the manual says), and the car always fires right up. But, it will only run for a couple of seconds, then stalls. Then I'm in the same boat as everyone else, and I need to crank 3 or 4 times to get it started again.

Is it possible that the problem is the check valvue in the pump is bad, and the pump to carb line is draining?

Thanks,
Matt

 

[D_B]

The line draining wouldn't be the issue. Enough fuel should be in the carb to keep it running without constant supply for quite a bit longer than you're experiencing.

I would be looking at the timing, and maybe a carb choke adjustment.

When was the last time the engine was timed, and how many miles are on the engine?

 

[6880 Mike]

My first suspect would be the choke.

:thumbsup:

 

[Slow & Leaky]

Is it a Qjet? That's classic leaking bowl symptom. Engine runs momentarily on what's leaked in then has nothing in the float bowl to pull from.

 

[walleyfisher]

Is it a Qjet? That's classic leaking bowl symptom. Engine runs momentarily on what's leaked in then has nothing in the float bowl to pull from.

Gotta go with this answer or the Choke setting is wrong.

 

[Rod75]

Gotta go with this answer or the Choke setting is wrong.

:agree:
I'll triple up on the above. Easiest to check choke and timing first. If necessary, then tear into carb.
:cheers:

 

[J.E. Caudle]

I would like someone to explain how timing could
cause this problem...:surprised

 

[010752]

You can have both problems drain and choke.

Just remove the air cleaner and have someone else do the start procedure.
You can see if the choke is set by the full pedal and watch for squirts from the accelerator pump.

If a qjet just use the filter with the check in it.

 

[tracdogg2]

72's can't drain fuel back. The tank is a bottom feed and is higher than the fuel pump. Fuel pumps can't drain carbs. The inlet needle is well above the jets. But a leaking fuel pump can drain the fuel from the pump to carb fuel line. See if you have any gas stains on the front of the right side motor mount.
Every knows quadrajets are notorious for the well plugs leaking. They will leak all the fuel from the float bowl into the intake. Sounds like the problem here. But the fuel in accelerator pump cavity won't drain out. That's why it will start and die. You have one good shot of fuel when you pump the pedal but the float bowl is empty. You have to crank and crank until you refill the float bowl and the accelerator pump.
Mike
P.S. Holleys have this same problem if the power valve is leaking.