Translations:KAVAN FS400AR - Instruction manual/16/en

Carburettor Cleanliness

It is vitally important for all engines, including the FS 400, that the fuel entering the carburettor is pure and clean. For this reason, it is recommended that the fuel is passed through a filter when the tank is filled and that a good in-line filter is installed between the fuel tank and the carburettor.
Additionally, occasionally remove the needle valve holder from the carburettor and rinse out the locations shown in Figures 5 & 6 with methanol or fuel. Be careful not to lose the gasket when removing the needle valve holder from the carburettor.