Today’s fuels have a short shelf life and it is recommended you buy no more than a two month supply unless using a suitable fuel stabilizer. GASOLINE Tecumseh Power strongly recommends the use of fresh, clean, unleaded regular gasoline in all Tecumseh Power engines. Unleaded gasoline burns cleaner, extends engine life, and promotes good starting by reducing the build-up of combustion chamber deposits. Leaded gasoline, gasohol containing no more than 10% ethanol, premium gasoline, or unleaded gasoline containing no more than 15% MTBE (Methyl Tertiary Butyl Ether), 15% ETBE (Ethyl Tertiary Butyl Ether) or 10% ethanol, can be used if unleaded regular gasoline is not available.   Reformulated gasoline that is now required in several areas of the United States is also acceptable. NEVER USE gasoline, fuel conditioners, additives or stabilizers containing methanol, gasohol containing more than 10% ethanol, unleaded regular gasoline containing more than 15% MTBE (Methyl Tertiary Butyl E