Post originale di: Joe Averyt ,
barbchenoz, I have a craftsman model 247.288841 19.5 horse riding mower with a Briggs one cylinder engine. It was a cast-off from a relative who was tired of taking it in to get the "gasoline in the oil" problem fixed. The last repair actually worked, but by then my sister-in-law was exasperated with it and gave it to me. The problem is the in the carburetor. It has a solenoid in the bowl which shuts off the flow of gas when the ignition is switched off. The design is faulty - the solenoid does not completely shut off the gas and so it allows a siphon action to empty the bowl into the intake manifold. The raw gas then leaks down the cylinder wall and into the crankcase. The repair shop gave up trying to fix it and installed a manual cut-off valve in the fuel line. You have to remember to open the valve before you start the engine and close it when you shut the engine off. I've been looking for a way to modify the carburetor to stop the siphon problem, but have not found a way to do it so far. In the meantime, the manual valve allows me to use the mower without ruining the engine. Don't run yours with gas in the oil - it thins the oil and will damage the engine. Hope this helps.