carb floods car stalls

grumpyvette · Jan 27, 2012

hey grumpy?
I have had constant issues with my old edelbrock carburetor not running correctly, so I purchased a new HOLLEY 650 cfm 4 barrel carb, the car starts, but floods out, theres fuel coming out of the carburetor dribbling over out of the vents even after I shut it off or it stalls if I try to keep it running

IT sounds like either the floats have not been set correctly or that the carbs got a clogged or defective needle & seat valve, thats common in older cars that have rust or crud in the fuel tank so you might need a tank cleaning and a new fuel filter or a new fuel tank and a new fuel filter or possibly the fuel pressure too high?
have you verified your FUEL PRESSURE REMAINS CONSISTENT in the 5.0 lb-6.0 lb range at the carb inlet port?
return style fuel pressure regulators tend to be far more consistent.you can,t correct problems until you isolate the cause, so start verifying the fuel pressure and float levels first then verify theres nothing assembled incorrectly or and defective parts.
as always when installing new parts, TAKE THE EFFORT TO READ THRU THE MANUFACTURERS INFO that came with the part before installing it
While your tuning it up?
have you verified tdc and the ignition timing curve?

How do I adjust the fuel level on my carburetor?
ANSWER Setting the fuel level should be the first thing you do before attempting to make any further adjustments.The float level should put the fuel level just below the bottom of sight plug hole. You will make the adjustment with the vehicle on a level surface and the engine idling. You will first remove the sight plug, then to make your adjustment you will need to loosen the lock screw on the needle and seat. This will allow you to turn the adjusting nut to raise or lower the float level. Each hex flat on the nut will change the float level approximately 1/32". When you have the fuel level just below sight plug hole you will then tighten the lock screw and reinstall the sight hole plug. Make sure you have a shop towel handy in case you have any fuel leaks from the Sight plug or needle and seat adjusting nut.

your not the first guy trying to track down an intermittent, drive-ability issue, or problem to find fuel quality and volume effects the engine performance.

one really handy thing you should have is a engine compartment mounted fuel gauge to show what the fuel pressure is with EITHER injection mounted on the fuel rail or with a carburetor on the carb fuel inlet line , a carburetor should have a consistent 5-6psi, with a a fuel injection system , youll need to verify the correct pressure in the factory shop manual, but on a TPI or LT1 its supposed to be in the 38-PSI -to-42- PSI range
return style fuel pressure regulators a properly sized fuel line, fuel filter and a fuel pump thats up to the job makes it much more likely to function correctly, and use of a vacuum gauge, timing light,fuel pressure gauge, IR temp gun, knowing how to be reading spark plugs correctly sure helps
GET A FUEL PRESSURE GAUGE AND MEASURE DON,T GUESS
how can you possibly set up your fuel system unless you know the pressure and flow rates required and what currently exist's

READ LINKS

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/fuel-pressure-regulators.635/

http://garage.grumpysperformance.com/index.php?threads/how-big-a-fuel-pump-do-you-need.1939/

http://garage.grumpysperformance.co...ss-fuel-pressure-regulators.12776/#post-65998

http://www.summitracing.com/parts/MRG-2975/

http://www.summitracing.com/parts/AEI-15632/

http://www.summitracing.com/parts/RUS-670353/?rtype=10

Grumpy · Apr 21, 2016

Hi all, I got my 73 out after winter storage. It has a 283 in it. I changed dht e plugs, oil and filter. Drove about 100 miles on the changed oil again. Went to start it up and it ran so rough I could nt drive it. Gas is pouring in the carb to and flooding under car. Any suggestions before I take it into the shop?

honestly this is very simple to check, and correct, the Holley, edelbrock and/or Rochester carburator have a fuel control or needle valve that is adjustable that controls fuel entering the carbs fuel bowls ,you should have about 5-6 psi coming from the fuel pump, and the floats are easily adjusted, you don,t need to do much more than a few simple checks or adjustments.
post pictures of your carb, and we can go from there!

if youve ever wondered why Ive suggested no one use the cheap glass fuel filters, its because they are prone to leak, with less than safe results.

YOU GENERALLY SET THE FLOATS TO JUST LET FUEL WET THE SITE PLUGS LOWER THREADS, BY ADJUSTING THE NEEDLE SEAT HEIGHT IN THE FLOAT BOWL

AGAIN PRESSURE AND FLOW RATE ARE TOTALLY DIFFERENT FACTORS
http://garage.grumpysperformance.com/index.php?threads/holley-carb-floods.11057/#post-49141

http://garage.grumpysperformance.co...u-need-to-know-setting-float-levels-etc.1115/

http://garage.grumpysperformance.com/index.php?threads/q-jet-info.1144/#post-51070.

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/

http://garage.grumpysperformance.com/index.php?threads/how-big-a-fuel-pump-do-you-need.1939/

http://garage.grumpysperformance.co...on-and-correcting-a-rich-edelbrock-carb.1820/

http://garage.grumpysperformance.co...-the-holley-4150-and-4160-series-carbs.10736/

carb floods car stalls

grumpyvette

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Grumpy

The Grumpy Grease Monkey mechanical engineer.