2003 Yamaha YFM400FAR Kodiak Factory Service Manual, Page 227Get this manual
CARBURETOR
8.Check: Free movement (piston valve) Sticks Replace the piston valve guide and the piston valveInsert the piston valve into the carburetor body, and check for free movement9.Check: Free movement (throttle valve) Sticks ReplaceASSEMBLING THE CARBURETOR