Yamaha F150B Service Manual page 306

LOWR
Adjusting the forward gear shim thickness (T1)
Measure the thickness of each forward gear shim (T1) in 2 places.
0.10
0.12
0.15
0.18
0.30
0.40
0.50
Total
Adjusting the reverse gear shim thickness (T2)
Measure the thickness of each reverse gear shim (T2) in 2 places.
0.10
0.12
0.15
0.18
0.30
0.40
0.50
Total
8-27
Lower unit
Number of shim(s)
Number of shim(s)
(mm)
Subtotal
(mm)
Subtotal