Just rebuilt my carb... fuel flowing out of Bowl vent holes!!

[OilPatch197]

I got a electronic fuel pump and I noticed when I try to start it, fuel just gushes out the fuel vent holes in the air horn!!

I just rebuilt this carburetor, Is my float set high? I am looking at the needle/seat/float area, going to do a "wet" float adjustment, any tips what to look for?


Model: 1984 with the 2150 Motorcraft carb.

I am thinking the pressure produced by the fuel pump must be low enough to allow the float to close the needle valve (about 6-7 psi). If fuel pump output pressure is too high, it will force the needle valve open against the pressure exerted by the float and the carburetor will overflow.

I have one of those "electronic" fuel pumps designed for carbed motors. I had the fuel pump on before the rebuild and did just fine, and I installed a new float.

So I need to bend the tab DOWN to shut off fuel quicker, but HOW can it flow out the float bowl breather tubes?

 

[Meddle]

Make sure there is no debris in the fuel bowl.I got some dirt in the carb after changing the fuel filter on my 72 Cougar and it made the needle valve stick open.And yes if the valve stays open the fuel goes right up the vents and spills over into the carb.Also the lower you bend the tab the sooner the valve will close,but check for dirt first before bending anything.

 

[John Smith]

is your needle seat gasket

one of those rubber coated metal ones? I bought a rebuilt one where that seat "gasket" wasn't sealing properly...

used an older fiber one and it is fine now....just something to check...is ur new float full of fuel?....I like brass myself...float level 7/16's-1/2 below bowl....?

 

[OilPatch197]

Can I press down on the needle and the flow of fuel should stop, correct?

is your needle seat gasket
one of those rubber coated metal ones? I bought a rebuilt one where that seat "gasket" wasn't sealing properly... used an older fiber one and it is fine now....just something to check...is ur new float full of fuel?....

Got to check this out tomorrow afternoon. Great Ideal, perhaps my Seat gasket is leaking. I can't check anything out further, as I don't like pumping out a lot of gas ($$$) so I need a hand to toggle the fuel pump.

 

[John Smith]

yes....

Can I press down on the needle and the flow of fuel should stop, correct?

hopefully your pump is putting out no more tan 6 or so lbx....and when the float is set correctly and reaches the full level it will shut the needle/seat..

i believe tha float level should be 1/2" below carb body when full...you can play with it somewhat...lower is better than higher...if it's too low it will starve when revved somewhat but still run...when too high it can flood....if you have a high flow pump lower is generally not as much of a problem....

I'd make sure your new float isn't "soaked"....and will actually float....(if you can get a brass float i would)

not recommended for non pros but you can run that engine w carb top off and watch it work.....

again definatley NOT recommended unless u KNOW what ur doing....are you sure ur pump is only putting out 4-6 lbs?.....

good luck

since an electric pump is so ON when the key is on....they are pumping b4 the engine is running..and everything needs to be top drawer....electric pumps are great.....but....

 

[kimcrwbr1]

I believe you want 7/16 wet float adjust measure from the top of the carb to the center of the fuel in the bowl not on the edge it is either the needle and seat or the seat gasket pull the seat out and make sure you either clean the click the fuel pump for a sec to push any thing out that may be in there or however you can assure the surface is clean then reinstall the seat and make sure it is good and tite as long as the seat is new you can use a new needle or even try the old one as long as the float can shut off the fuel and if the fuel pressure is too high a different pump or a fuel pressure regulator is needed.