Kawasaki 31 hp engine with 1,140 hours blew this morning (60 inch Super Z). It sounded like I had run over something, then the mower shut down. Engine had a hole in it between the oil filter and the dip stick. Engine has always been serviced between 30 and 50 hours intervals with filter replaced at each change. Any ideas on what could have caused this early engine failure? Anyone ever have any luck getting price break from Kawasaki for early engine failure after expired warrenty (mower is five years old)?