Bad deal - below is a pic of a piston from a John Deer 4455 tractor. The engine developed a micro crack and a small amount of coolant made its way to the oil galley. Once there it set up a nice reaction to seize the piston and allow for pre-detonation to occur. The result....BANG! and about $12 large to fix and a nice 'hand grenade' part I use for training.
