Specifications and requirements another outboard motor manufacturer’s factory-brand TC-W3 oil. damage or engine performance problems. It is recommended that you install a water- separating marine fuel filter assembly (10 micron minimum) between your boat’s fuel tank and outboard motor when using etha- nol. Ethanol is known to allow moisture to be absorbed into boat fuel tanks and systems. Moisture in the fuel can cause corrosion of metallic fuel system components, starting and running complaints and require addition- al fuel system maintenance. EMU36360 Fuel requirements EMU36780 Gasoline Use a good quality gasoline that meets the minimum octane rating.
If knocking or ping- ing occurs, use a different brand of gasoline or premium unleaded fuel. Yamaha re- comends that you use alcohol-free (see Gasohol) gasoline whenever possible. EMU27270 Ring Free Fuel Additive Gasoline is a precise blend of many different substances, each chosen to give certain characteristics. Gasoline blends have been changing in recent years in response to con- cerns about pollution and resulting emis- sions regulations. One of the most obvious changes has been the elimination of lead from most fuels. As gasoline has changed, the amount of ad- ditives such as aromatics and oxygenates has increased.
These additives are impor- tant for the engines in passenger cars, but they can have detrimental effects in marine engines, because of increased deposits in the combustion chamber. When enough de- posits collect, piston rings begin sticking. Performance drops and engine wear in- creases dramatically. While many additives available may reduce deposits, Yamaha recommends the use of Ring Free Fuel Additive , available from your Yamaha dealer. Ring Free Fuel Addi- tive has repeatedly proven its ability to clean combustion deposits from inside the engine, notably the critical piston-ring-land area, and fuel system components. Follow product la- beling for use instructions. Recommended gasoline:
Regular unleaded gasoline with a min- imum Octane rating of 86 (Pump Oc- tane Number) = (R+M)/2 ECM01980 NOTICE Do not use leaded gasoline. Leaded gasoline can seriously damage the en- gine. Avoid getting water and contaminants in the fuel tank. Contaminated fuel can cause poor performance or engine damage. Use only fresh gasoline that has been stored in clean containers. Gasohol There are two types of gasohol: gasohol con- taining ethanol (E10) and that containing methanol. Ethanol can be used if the ethanol content does not exceed 10% and the fuel meets the minimum octane ratings. E85 is a fuel containing 85% ethanol and must not be used in your outboard motor.
All ethanol blends containing more than 10% ethanol can cause fuel system damage or cause en- gine starting and running problems. Yamaha does not recommend gasohol containing methanol because it can cause fuel system 16