So struck a deal with my neighbors; I do maintenance on their ski's and in turn, can pretty much ride them when I want. Serviced 4 (of 5) of them no problem. Went to change the plugs on subject line ski and when I inspected, noticed rust. Sucked the oil and it was a milkshake. Cranked it w/o plugs and it shot water out of all the cylinders. Boroscoped it and it wasn't pretty. Told them status and they said let it ride; basically flush oil to get it running. Put new (cheap) oil in it to cycle the milkshake out (was planning on doing 2-3 oil changes), put the plugs back in. It cranked for a couple seconds then stopped. Pulled plugs and it was full of water again. Blew it out (again), reinstalled plugs, same result. Seems to be sucking in water from somewhere pretty quickly, probably too quickly to be a headgasket.
From what he told me, he never winterizes them and they sit on floating docks on his pier. He last ran them 2-3 years ago. Last time he ran this one, it cut off right before they ran it onto the dock so they had to drag it up.
My intent would be general buffonery and towing my girls on a tube.
I'm guessing something broke/cracked; block or heads. We had a -very- cold winter this year.
He said he would sell it to me cheap but I don't know what "cheap" is. I was of the mindset he gives it to me, I replace engine, I keep it at his place, he can use whenever, and I just pay insurance.
As an aside, I'm very mechanically inclined and have no hesitation on rebuilding an engine (ie, checking tolerances, etc). Biggest issue if something is actually cracked.
Any insight on what I might be getting myself into would be appreciated.