I've had a series of intermittent problems since I purchased this, involving poor starting and /or rpm limited to 2500 rpm. Dealer can't find the problem, doesn't do it for him. When I got the boat out this spring, I started out with the low max rpm problem, that went away, then had the siren going off for low oil pressure. Dealer first said it was the sender, replaced it, now says it has no oil pressure and is trying to figure out why - not sure he has much experience with 4 strokes - Also, I noticed some oil in the base area at floor of engine, not sure where it could come from. Any ideas what problem could be?