Hello everyone,

I am on my second remanufactured carb from advance auto and both of them are giving me the same problem. Carb is the Holley 2bbl stock carb

1951 F1 8BA Flathead

The carb pours gas out of the accelerator pump tube on the passenger side of the carb. I am running 2 lbs of fuel pressure at my regulator so I dont think over pressure is the issue.

What would cause both carbs to do this? Is it something I am doing wrong or is this a common problem? Im not even sure what seals the rod to the bore so gas doesnt leak out.

Any help or suggestions would be greatly appreciated!

 

I'd guess that during shipping the float is coming out of position, maybe the needle is even falling out.

 

The fuel level in the carb is controlled by the needle valve and at the correct fuel level you will not see gas coming out the accelerator pump area. The carb should certainly be able to handle 2 psi. I vote for leaking valve also.

 

Is this an easy fix?

I know the top of the carb can come right off with about 5 screws. What do you have to do from there once you are inside to see the problem?

 

The valve discussed is where the fuel line connects to the carb. With the top removed from the carb the float and needle valve that allows fuel to flow or not flow into the carb is readily visable. When you remove the top from the carb you should see fuel in the bowl of the carb, maybe half an inch from the edge. I say half inch as a rough swag, someone may have exact dimensions. When you turn the top of the carb upside down the float should move freely in both directions, thus opening and closing the needle valve. Careful, the small rod the float swings on can come out........but is easily replaced, just don't loose it. In fact, if the float is moving freely and moving the valve, pull the rod mentioned, remove the float and check the valve seat for being tight. The valve seat should have a gasket under it. Now, if all this is ok, blow into the fuel inlet and raise the float. Air flow thru the fuel inlet should stop with the valve closed. The float is adjustable to control fuel level. Get to this point with these checks and if nothing is found wrong, come back with a status report.
We have a carb expert or two here on the forum.

 

Here is the complete, official manual for the later Y-block version of the Holley 94. It tells how to set the float and (just as important) set the float drop.

The Old Car Manual Project: Manuals and tech info online

 

Is there a seal or or ring for this accelerator pump tube? I just find it odd that 2 completely remanufactured carbs are pouring gas from the same spot

 

From that manual it seems as if there is a felt seal that is supposed to be in place to prevent fuel from leaking down the acceleretor pump tube. I am thinking mine is not working properly or is dried out. Is there something I can do to recon dition this seal to make it do what it is supposed to do?

I think I may just go to advance and order a 3rd one. For $200 you would think it would just work.

 

Maybe the same guy made the same mistake twice? That carb is pretty simple. The manual that Ross recommended for you should help. It even has pictures for guys like me.

 

Mine was float level alone. Newly rebuilt carb from a respectable vendor. The float stop level can range from 1 5/16 to 1 15/32 depending on application. Float was set too high and not ever completely shutting the valve (needle). Gas poured out on the passenger side around the accelerator pump. Hated to take the top off a fresh carb but adjusting the float level properly with the top upside down fixed the problem.

 

I'd want to pull it open just to make sure what jets they put in it, too.

 

Felt seal is just a dust seal. Early carbs had a brass bushing instead of the felt. I'm with the others. Check the float. Also, check the needle valve. Some newer needles have a rubber tip that don't like new gas. Some grades of viton rubber handle any type of gas.

If you have an old carb around, check if it has a steel valve. If so, put it in your carb when you monkey with the float. Tap it lightly with a hammer to "set" it in the brass seat.

 

Thanks for all the advice guys, I'm sure I'll need it when my third carb from advance comes in. It will be here Thursday so I'll probably bolt it on Friday night and try again. What I don't get is how the float isn't just set when you take it out of the box.

 

They probably are set, but they weren't designed to be bounced up and down, while upside down. That is what kind of treatment they get in transit.

 

Just to answer your question: Is it something I'm doing? The answer may be yes. Is there a good fuel filter in place? Or, are you filling the nice clean carbs with rust and debris? If you are pumping the carb full of crud, then the needle may not be able to seat and viola, there's the problem. Jag