Yesterday i was mowing about 8 acres with my grasshopper 223 with a 23 hp kohler about 100 hours on the machine anyway i had been on it for about 2 hours and i turned a corner and notices a plume of white smoke billiowing out from behind me of course it scared me i shut it down so fast and jumped off. After a few seconds of breez cleared the smoke i got to lookin over the engine. Anway the dip stick cap had poped up and off to the side and it was spewing oil all over the hot muffler. The oil was not over filled i know for a fact because i checked it befor i started mowing the only thing i can figure out is that i didnt get the cap on all of the way but i know it wasnt off for very long because the i checked the oil level when i got off and it was a hair about the fill line. Now on the engine it says it has oil sentry protections, so does this mean that once the engine looses oil pressure it was shut it down? I am mostly wanting to know if i did any true damage to the engine? I put oil back in to and it started right up and i finished mowing for about 2 more hours with it and it didnt miss a beat. Just curious about what exactly the oil sentry protection is?