Treating the Fuel System
As the riding season draws to a close, Polaris recommends riders begin treating their snowmobile’s fuel system with Polaris Carbon Clean or similar commercially-available fuel stabilizer.
Treating the fuel system with Carbon Clean during the last few
            rides of the season ensures the entire fuel system is treated.  Then,
            when it comes time to store the snowmobile, all the rider has to do
            is completely fill the fuel tank with fresh, non-oxygenated fuel and
            treat the new fuel with Carbon Clean. 
It is also recommended
            riders use non-oxygenated fuel during the last rides of the season
            as non-oxygenated fuel stores better than oxygenated fuel and resists
            water vapor absorption.
If the rider was unable to
            treat the fuel system and/or use non-oxygenated fuel at the end of
            the riding season, the rider should do the following:
- 
               
               The rider should consume as much fuel in the fuel tank as possible during the last rides of the season. 
- 
               
               When performing the summerization storage procedures, fill the fuel tank completely with non-oxygenated fuel. Note that most oxygenated fuels contain ethanol. Since ethanol is hydroscopic, oxygenated fuel will absorb a small amount of water vapor during the storage season and more so in humid locations. Completely filling the tank with non-oxygenated fuel minimizes water vapor absorption during the storage period and limits the amount of air and water vapor that can accumulate in the tank. 
- 
               
               Treat the fuel in the fuel tank with the recommend amount of Polaris Carbon Clean. The recommended mixing ratio is outlined on the bottle label. 
- 
               
               Position the snowmobile outside in a well-ventilated area. 
- 
               
               Start and run the engine for 10-15 minutes to distribute the treated fuel throughout the fuel system.