Small Engines (Lawn Mowers, etc.): gas leaking thru muffler, air filter assembly, ambient air temperature

Question
Have a Sears mower with a Kohler 16 hp engine CV 460. recently the mower has started to leak gas thu the muffler while sitting in the garage after use. Have rebuilt carb but still does it. Carb is equipped with fuel shut off solenoid.  Any suggestions? Thank You.

Answer
The fuel shutoff solenoid in the carburetor only stops the fuel from going up the Main nozzle.  There is still a float , needle and seat in the carburetor.  But if you have rebuilt it as you say then it should be okay.  Other ways that this happens would be the engine running extremely rich and the engine not consuming all the fuel.  Another thought would be cold ambient air temperature and the engine not being run until fully warmed up.  There will be condensation inside the muffler and that could be dripping also but these are really out there.  I still go back to the needle and seat in the carburetor even though there is a fuel shutoff solenoid the carburetor can still overflowing it will just take a different path to doing Venturini of the carburetor.  What I'm surprised of is that your oil level is going up because of the fuel.  Normally when this happens the excess gas will run into the crankcase more so than out and through the muffler.  The excess oil and gas usually ends up in the cylinder because it ends up going through the breeder and into the air filter assembly behind the element.  There should be a small rubber to attaches to the back of the air filter assembly typically that's where it would come out and run through the engine if there was enough it would push past any open valve and directly into the combustion chamber.  This engine has to be smoking heavily.  It will take some time to burn out what is in the muffler assembly.  Once you're done replaced the spark plug.  I hope this information has help you out.