This engine died as it came off full power to pull into the dock. The mechanic that has my Yamaha told me he thinks the head gasket blew between the two cylinders. If so - that is about $20
I am not sure about the oil, but I always run the gas out when done for the day and use fogging oil when the engine sits over the winter. I left a motorcycle at flight school for 3 months once and when I got back the engine was frozen solid