Yamaha Marine Outboards F4A/F4 Factory Service Manual, Page 228Get this manual
PROPELLER SHAFT ASS'Y
SERVICE POINTS
Dog clutch inspection 1Inspect: 9Dog clutch WearDamage Replace
Propeller shaft inspection 1Inspect: 9Propeller shaft WearDamage Replace
Dog clutch and shift spring installation 1Install: 9Shift spring 1