Took the boat out today. Everything ran fine last weekend by the way. Today, things were sluggish, the engine would get up to 3800 rpm and were still slower than a turtle, then it would start picking up slowly/gradually. Suddenly I start hearing a whirring noise coming from the engine, I slow the throttle, it starts getting shaky, then it just seizes up and died. I take the engine cover off and see a pool of oil. Engine is most likely dead at this point, but i'm just trying to figure out what happened. anyone have a guess?