Useful small engine tips

How to minimize fuel system problems


Purchase only the amount of fuel that will be used in 30 days
Fuel deteriorates over time. Deterioration begins with the most volatile compounds evaporating. Once evaporation reaches a certain point it will be hard/impossible to start the machine. As more compounds evaporate, the fuel will form brown gummy deposits in the system. Given enough time the gummy deposits will become a hard varnish. Gummy deposits and varnish can plug passages in the carburetor preventing the engine from running or causing the engine to run poorly (surging, lack of power, stalls, etc.). Deposits can also cause the carburetor to leak fuel if they prevent the float needle from sealing properly


Do not use gasoline with more than 10% ethanol by volume
Engines produced to date for use in outdoor power equipment are not designed for gasoline with more than 10% ethanol (such as E15, E20 and E85); using higher ethanol fuel blends may lead to engine damage and/or performance issues. We recommend individuals read the Engine Operator’s Manual and Equipment Operator’s Manual for information on what fuel can, and cannot, be used in their machine and to understand applicable warranty coverage and exclusions.

Consider using gasoline without any ethanol (E0)
Gasoline with no ethanol will greatly reduce the amount of moisture the gasoline can absorb from the atmosphere. Many areas of the country have ethanol-free gas available, and finding it is easy. Search for “ethanol free gasoline” on the Internet.


Add fuel stabilizer to the fuel the day you buy it
Most fuel stabilizers form a layer over the top of the gasoline and greatly reduce the rate the fuel’s volatile compounds evaporate. They also prevent the absorption of moisture by the fuel. If fuel stabilizer is added to gasoline the day the gasoline is purchased, the fuel will stay fresh longer. AMSOIL Gasoline Stabilizer and AMSOIL Engine Fogging Oil applications include, but are not limited to, motorcycles, snowmobiles, ATVs, outboard motors, stern-drive and inboard marine engines, personal watercraft, lawn equipment, chainsaws, snowblowers, portable generators, handheld power equipment, motor scooters, powered farm equipment, powered construction equipment, cars and trucks. For short-term storage, AMSOIL Quickshot® (AQS) should be used.