Small Engines (Lawn Mowers, etc.): John Deere 425, john deere 425, riding lawn mower

Question
Hello,

I have a John Deere 425 riding lawn mower with a Kawasaki V Twin engine.  It's having a problem with (I'm guessing) the left cylinder/piston.  When I mow for about 30-45 minutes or if I mow in tall grass, the engine bogs down and starts spitting out white-ish smoke (if I remember correctly).  The engine will continue to run rough and spit out smoke until you shut it off.  I shut off the engine and remove the left spark plug and it looks fouled.  After I clean the spark plug and replace it, it works just fine for another 30-45 minutes.  I have done top end rebuilds on two-stroke motorcyles before.  I'm guessing that the problem with the mower is that the piston and rings need replacing because engine oil is passing by the piston rings into the combustion chamber.  Does this sound like the right idea?  If so, do you know where to find more information on rebuilding the engine?

Thank you,

Tom

Answer
It sounds like it probably is just a failing head gasket on that
side, which if you are hand with tools, should be an easy repair.
   You can view an illustrated parts list by going to kawpower
and going to parts lists, and entering your engine's model numbers.

Just to be sure that the carb is not flooding, and the excess fuel is getting into the engine oil, another possibility, look at and sniff the oil, if it is real thin, and smells like gas, then your carb is the problem.