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Briggs 12H802 leaking gas from primer bulb

Posted by asand211 Georgia (My Page) on
Wed, Apr 18, 07 at 13:11

Mower is about 7 or so years old and started leaking gas from primer bulb. Anytime gas is put in tank it immediately begins pouring out of primer bulb. The float moves freely and the needle have is in perfect shape. The only thing is there is no rubber gasket in the valve seat or on the end of the valve. Just metal on metal. Is that normal? I bought a gasket kit from Jacks Small Engines and the only gasket even close to that size is too large. What am I missing?

Follow-Up Postings:

RE: Briggs 12H802 leaking gas from primer bulb

What is the type on it?
From what I can see, most likely the flange of the bulb acts as the gasket. Replacing the primer assembly might solve your problem (only about $5). That contains the bulb itself, so if it is just a case of the bulb getting deteriorated, that should fix it right up. I guess it is also possible that the mount on the filter box is warped, which could also cause it.

RE: Briggs 12H802 leaking gas from primer bulb

The gasket kit doesn't contain the needle AND seat. You need the carb overhaul kit for that.

Inspect the float. If it's hollow, shake it and listen for a "slosh". Silence is good. If solid, make sure it's not "fuel logged".

With the needle removed, pour a "bit" of gas in the tank to flush the line and hopefully any debris that might be lodged in the seat. Be safe etc. etc.
If that doesn't work, you'll probably need a new N&S.

IPL at the link in case you don't have it.

Here is a link that might be useful: IPL

RE: Briggs 12H802 leaking gas from primer bulb

There should be a rubber viton seat for the Needle valve to close against. From your description, Fuel is flowing past the float valve and flooding the carburetor. You probably have some fuel flowing into the intake valve and crankcase area. Check the dipstick to see if the crankcase has fuel. The primer bulb is probably ok - it normally is an air pump that pushes fuel from the float bowl to the venturi area of the carburetor.

RE: Briggs 12H802 leaking gas from primer bulb

Be sure to read the needle and seat installation instructions. The "rubber viton seat" as mentioned by larryf probably needs to be installed in a specific direction. The seat will probably have a little depression all around it on one side and should be installed in the up (away from the float) position, the smooth side goes toward the float.

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