Small Engines (Lawn Mowers, etc.): Kawasaki - Cub Cadet - SRC 621, blown head gasket, cub cadet src 621

Question
I have a Kawasaki - Cub Cadet - SRC 621 mower and I am having a problem getting it started.  It used to start right up on the first or second pull of the started chord but now it takes 5-8 pulls to get it started even after it is warm.  I have done routine maintenance (oil change, air filter, check the spark plug) with no success.  Any suggestions?  Thanks in advance.

Answer
Remove the air filter  and shoot a quick 3 second burst of carb cleaner down the carb.
If it starts right up, clean the carb.
If the engine is still hard to start you probably have a blown head gasket. This engines original head gasket was prone to blowing out between the cylinder and the push rod galley.The new head gasket has been redesigned to solve this problem