1998-2006 Yamaha F20/F25 Outboards Service Manual, Page 107Get this manual
SERVICE POINTS
Do not use steel wire to clean the jetsThis may enlarge the jet diameters and seriously affect performanceCarburetor inspection 1Inspect: Carburetor body Cracksdamage ReplaceContamination Clean2Inspect: Main jet Pilot jet Main nozzle Contamination 3Inspect: Needle valve Grooved wear 4Inspect: Float Cracksdamage