1998-2006 Yamaha F20/F25 Outboards Service Manual, Page 255Get this manual
ILOWRI T3
SHIMMING (EXCEPT FOR USA AND CANADA)
SHIM SELECTION (EXCEPT FOR USA AND CANADA)
Pinion gear shim
Find the pinion gear shim thickness (T3) by selecting shims until the specified measurement (M) is obtained with the special tool
1Install: Pinion height gauge Drive shaft Drive shaft bearing Pinion height gauge: 90890-06702 Drive shaft holder: 90890-06517
Attach the pinion height gauge to the drive shaft so that the drive shaft is centered in the gauge's hole After the wing nuts contact the fixing plate, tighten them another 14 of turn2Install: Pinion gearPinion gear nut: 50 Nm (5.0 kg, 36 ft Ib)