Measuring The Forward Gear Backlash; Adjusting The Forward Gear Shim Thickness (T1) - Yamaha F150A Service Manual

Example:
Measurement point "a"
Measurement point "b"
Measurement point "c"
Measurement point "d"
Average
Round-down average (M)
11. Determine the pinion shim (T3) thickness
adjustment using the "Pinion shim (T3)
selection table" according to the rounded
average (M) and the deviation (P)
stamped on the lower case. See "Pinion
shim (T3) selection table" (A-12).
TIP:
The (P) mark "a" is stamped on the trim tab
mounting surface of the lower case in
0.01 mm units. If the (P) mark is unreadable,
replace the lower case.
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40,
0.50 mm
Example:
(M) = 0.24
(P) = –3
F +2
P –3
(T3) = 0.95 mm from the "Pinion shim (T3)
selection table".
–2
Stamped
value on the –3
lower case (P)
–4
(mm)
0.24
0.24
0.25
0.25
0.2450
0.24
R +4
a
Pinion height
measurement (M)
0.23 0.24 0.25
0.95
Shimming (regular rotation model)
12. Remove the special service tools, and
then install the determined pinion shims
(T3).

Measuring the forward gear backlash

• Spray anti-rust lubricant on the gear and
bearings before installation. Do not apply
gear oil to the parts. Otherwise, correct
measurements cannot be obtained.
• Keep the parts free of foreign material,
such as dirt and lint.
• When measuring the forward gear or
reverse gear backlash, use the original
bearings and shims.
1. Install the original forward gear shims
(T1) and taper roller bearing outer race.
TIP:
• If the original forward gear shims (T1) are
missing, install new shims with a combined
thickness of 0.55 mm.
• Do not reuse a shim if deformed or
scratched.
2. Install the forward gear assembly, drive
shaft, and pinion. See "Installing the drive
shaft" (8-25).
3. Check that the drive shaft turns smoothly.
4. Install the
assembly. See "Installing the propeller
shaft housing assembly" (8-26).
5. Check that the drive shaft turns smoothly.
6. Measure the forward gear backlash. See
steps 3–15 in "Measuring the forward
gear backlash and reverse gear backlash
before disassembly" (8-35).
Forward gear backlash (F150A):
0.15–0.61 mm (0.0059–0.0240 in)
Forward gear backlash (F150B):
0.15–0.68 mm (0.0059–0.0268 in)
Adjusting the forward gear shim
thickness (T1)
1. Remove the taper roller bearing outer
race and forward gear shims (T1).
8-41
propeller shaft housing