Read about a product call Star tron by Star Brite in Outdoor Life it is a fuel conditioner and stabilizer.Also deals with the ethanol alcohol problem in gas we get now their site has a page on what ethanol does to gas how it separates in your fuel tank and how it is a solvent and dissolves gum and varnish in your tank it also absorbs the water in your tank could get expensive if there is old fuel or your tank is older. They have a toll free phone number for info. 1-800-327-8583 Price was about the same as stabil 1 oz per 15 gal.