Small Engines (Lawn Mowers, etc.): Sears model 917270771 riding mower 19 hp, briggs and stratton, piston rings

Question
my son purchased a used sears riding mower, a 19 hp model 917270771 which suddenly stopped running.  It wants to start but gasoline floods the spark plugs and comes out the exhaust manifold.  The battery is new, the air filter is new, spark plugs are new, and fuel filter is ok..there is no visible signs of leakage in any hoses..what could be the problem and can we fix it or does a professional have to fix it..It is a briggs and stratton engine ..a turbo..i think it is a 1999..Thanks for your help

Answer
Check the oil level and see if it smells like gas.

Frequently, the carburetor inlet needle doesn't seal properly allowing gasoline to flow into the engine.  This thins the oil and causes it to flow past the piston rings where it is either burned or exspelled via the exhaust system.

Inlet needles are easy to replace compared to the seats.  Many times just replacing the inlet needls solves the problem.  

To replace the needle you will have to remove the carburetor float bowl and float.  This can be done without removing the carburetor but you have to be careful with the float bowl o-ring seal.

If you do the repair yourself make sure you change the oil.
Let me know if  you have any other questions.
Eric