" From: Ken Ames <ameskg@xxxxxxxxx> " " In my experience a full tank will last a couple years anyway, but less " than full won't last as well. It seems with room for evaporation the " fuel will tend to go bad. maybe it's the amount of trapped air? a half-full tank has more oxygen available to react with it and form gums than a full one. ________________________________________________________________________ Andrew Hay the genius nature internet rambler is to see what all have seen adh@xxxxxxxxxxxxxxxxx and think what none thought