2005 Polaris Sportsman 400/500 Service Manual, Page 126Get this manual
FUEL SYSTEMCARBURETION
CARBURETOR ASSEMBLY
Inspect the diaphragm (A) for holes, deterioration, or damageMake sure the diaphragm is pliable but not swollenThe diaphragm should fit properly in the carburetor bodyReplace diaphragm assembly if diaphragm is damaged
5Install the pilot mixture screw, spring, washer, and O-ring as an assemblyLubricate the O-Ring with oil or light grease before installationCAUTION: Do not damage the O-ring during installationTurn the screw in until it lightly contacts the seatBack out the specified number of turnsNOTE: The final pilot (idle) mixture must be adjusted with the engine runningPilot Mixture Screw Base Setting (Set at Factory) Refer to Specifications in Ch1