I have had conflicting advice on this. I have been storing my 1989 17ft Ebbtide, 100hp Merc outbourd, inboard gas tank, with the tank full + stabiliser. The theory I was told is that this prevents condensation in the tank, whereas if it is empty or part full, the evil Ontario winter will guarantee water in the tank in the long run. So far, so good, but is there a better way? Grumps