Small Engines (Lawn Mowers, etc.): oil blowing out muffler, blown head gasket, bunton lawnmower

Question
I have a bunton lawnmower with a kohler 25hp it is blowing oil out the muffler and fouls out sparkplug I pull the plug out and it is all covered with burt oil,do you think these is a ring problem

Answer
Depending on the age and maintenance of this unit, I would first consider a blown head gasket as the issue. I really don't know what engine this is, but if it's a OHV, this is entirely possible. If it's not a head gasket, most likely it's a ring or piston problem.