I have a 1984-85 holley 4 barrel and it has an electric fuel pump. the pump keeps running and the carb. overflows with gas. does the carb have a float to automatically stop pump? if not, how do i fix the problem? the motor is a ford 460
Electric fuel pump most likely has too much pressure for the carb. AFAIK, the Holley 4150/60 & 4165/75 should each demand the usual 4.7-5.3 PSI (4.7 @ idle, 5.3 @ max RPMs), so even the Holley red pump would need some restriction from a regulator. If you want this to be adjusted to its best efficiency, you need to have a fuel pressure gauge installed temporarily, if not on the regulator like I have on my Scout II. FWIW, the regulator I have installed is the Mallory 4307M from CenturyPerformance.com, Summitracing.com, Jegs.com, etc.
http://www.malloryperformance.com/pdf/4307M.pdf
A bad Needle & Seat will do this also, or debris stuck between the Needle and the Seat. This is where light tapping on the bowl helps, but it's best to run the fuel out of the bowl a few times and then the volume flow, or quick filling of the bowl, should loosen up the debris.
You also could have set he fuel float too high. What model carb, the ones I mentioned above (AKA Holley Modular Carbs)? If so, then Holley's site has a tech center & instructions on setting the float(s). www.holley.com
Set the floats carefully and slowly/gradually. Make sure the lock screw is always loose enough before turning the adjustment nut. If you strip out the bowl's threads on an older carb, you'll beat hell finding a replacement. 1/12 turn = 1/32" of fuel height IIRC. You set the fuel level, with pump running (wrap a rag around the carb so gas doesn't leak onto the manifold!!!) so the fuel is just starting to dip out of the "peep-hole" in the side of the float. Removal of the peep/seep-hole screw/plug is necessary first. Clockwise rotation of the nut lowers fuel level IIRC and counter raises fuel level. Again, please check their website. Most people get discouraged when dealing with the Holley Modular Carbs, but they are the simplest and the best carbs on the market. Even if 30+ years old.
Testimonial: "ty very much..i wil try to adjust "
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