I seen on a pump the other day that sold ethanol gas (which I try to avoid) The sign said "DO NOT use gas with ethanol in it in your lawnmower, as it will ruin your carburator and void your warranty" I've had really old gas start and run an engine, and Ive seen gas thats only a few months old not work at all. I won't drain out a tank if its only a few months old, but I will put in new gas with the old gas. As for Sta-bil... Im not a believer in it. I've used it before but seen no real results. Its the gumming up in the carb thats bad, not so much in the tank.
