2004-2006 Honda FourTrax Rancher TRX350TE/TM/FE/FM Service Manual, Page 104Get this manual
FUEL SYSTEM Be careful n01 10 damage rhe dIaphra gm
Turn the needle holder counterclockwise by using screwdriver while pressing it in and release the holder flange from the vacuum pistonRemove the needle ho ld er, spring, jet needle and washer
Check the jet needle for stepped wearCheck the vacuum piston for wear or damageCheck the diaphragm for pin hole, deterioration or damageCheck the vacuum piston for smooth operation up and down in the carburetor body will leak out of the vacuum chamber if the diaphragm is damaged in any way, even with just pin hole