I have a murry riding lawn mower with a B&S 14.5 hp OHV that for some reason the head fills up with gas. I have to remove the spark plug and crank over the engine to blow out all the gas, but when I replace the plug, it fires up and run great. What can be causing this to happen, and how can it be fixed?

John Van-Scoy, May 2008

Chances are there is fuel leaking past the float needle valve. When the engine is running, it uses the fuel faster that the leak replenishes it, but when the engine is stopped, float chamber over-fills, and fuel comes up through the carb jet and runs into the engine.

Solution - remove float bowl and float, clean/replace needle and/or seat, and re-assemble.

phil_saunders@bigfoot.com

Phil Saunders, May 2008

I think you need to strip and clean the carburettor - the fuel level is too high, maybe because the float needle valve isn't sealing properly, causing the engine to flood. It also helps to turn the fuel off at the tap every time you stop the engine.

John, May 2008