Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem

Carb not squirting fuel after warmup

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59bluesilver:
Nice morning, went for a drive. After about 30 min., it started bucking from a stop light an died. Luckily I was able to coast to a filling station and filled up. Started and took off, got about 1/4 mile, bucked again and died. Checked the carb and saw the squirters weren't squirting fuel. I was about 3 miles from home. I let it sit for 5 min. or so, would start and go about a block where it would die again. Did that procedure over & over till I got home. On the last leg, it seemed to run fine, going about a mile where I finally reached home and shut it off. Yesterday went out for a drive again and the exact same thing happened.

New fuel sending unit with sock filter, new electric fuel pump with new in-line fuel filter, new fuel hoses and new carb filter.

What is the problem, it has to be inside the carb? I have a '69 4MV Quadrajet, 7029202

motorvation2go:
First thing I would check is the carb inlet filter.
Assuming that proves clean and unobstructed, I'd next tee in a fuel pressure gauge near the carb inlet.
Plumb things safely (hose routing secure and leak proof).
Tape the gauge to the OUTSIDE of the windshield and watch what's happening with the fuel pressure while driving (locally!).   ;)
If pressure is insufficient then maybe a dirty (rusty) fuel tank has messed up the new sock and inline filter?

Are any lines real close to hot exhaust system components? Vapour lock a possibility?

Was the carb cleaned and set up properly with good (Cliff's) parts?
If not the case (but pressure reads good before the carb during operation), maybe you have a leaking/sunk carb float.
Dirt in carb passages?
Hope this gives you a couple of first steps.
Good luck with the fix.

59bluesilver:
Thanks for replying, I'll check out and do those things. What should the pressure be? I want to find the trouble and get it running. Then this winter I'll rebuild the carb right (I hope!).

429bbf:
some where between 5 to 7 no more no less .while your rigging up your tee to check pressure id stick the end with the gauge in a bucket and turn on the key and check flow first.that would give you an idea like motorvation2go said if your sock has plugged again.remember pumps don't make pressure.they only move volume and the restriction causes pressure.fwiw

motorvation2go:
Good point... good advice 429bbf! 
Yes check flow with the 'gauge' hose end open and discharging into the bucket.
Put out your cigarette for a minute or two.   ;D

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