Small Engines (Lawn Mowers, etc.): deere l110, crankcase, flywheel

Question
I have a l110 that used to run fine.  It currently fouls the spark plug after 1 hour of use (after I had it in for service).  I check the oil, and it seems there is too much oil in the machine.  The plug fouls so much, the machine ends up not running.

I have changed the plug, and the machine started (last week).  This week, I change the plug, and I get the engine to "turn" (electricity to the motor), but, it seems, no spark--no "catch" if you will.

Could it be I don't have the plug tight enough?  Or is there something else I should be worried about.

Gas is getting to the engine, engine turns, it just doesn't catch.

Thanks.

Answer
Hi James
 Not knowing what engine you have, I'll have to be general in my answer. First off, if the plug is "fuel-fouled", your problem could be a carb flooding problem or you are not getting spark to the plug. If the plug is "oil-fouled" then your problem could be an overfilled crankcase. First thing I would check would be the flywheel and magneto arms for oil and trash buildup which would cause a no spark or weak spark situation.