Yamaha F50 Service Manual

							62Y3A116-62
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ÈFor USA and Canada
ÉFor worldwide
CAUTION:
Do not reuse the bearing, always replace
it with a new one.
Disassembling the lower case
1. Remove the taper roller bearing outer
race and shim(s).
ÈFor USA and Canada
ÉFor worldwide
NOTE:
Install the claws as shown.
2. Remove the drive shaft bearing outer
race, shim(s), and drive shaft sleeve.
ÈFor USA and Canada
ÉFor worldwide
NOTE:
Install the claws as shown. Slide hammer and adapters 2
: YB-06096 
Stopper guide plate 3
: 90890-06501
Stopper guide stand 4
: 90890-06538
Bearing puller 5
: 90890-06535
Bearing puller claw 1 6
: 90890-06536
Slide hammer and adapters 1
: YB-06096 
Bearing outer race puller 2
: 90890-06523
Outer race puller claw A 3
: 90890-06532
Slide hammer and adapters 4
: YB-06096 
Stopper guide plate 5
: 90890-06501
Stopper guide stand 6
: 90890-06538
Bearing puller 7
: 90890-06535
Bearing puller claw 1 8
: 90890-06536
Drive shaft and lower case (T50/FT50B, FT50C) 
						

							LOWRLower unit
6-6362Y3A11
3. Remove the needle bearing.
Checking the pinion and forward 
gear
1. Check the teeth of the pinion, and the
teeth and dogs of the forward gear for
cracks or wear. Replace if necessary.
Checking the bearings
1. Check the bearings for pitting or rum-
bling. Replace if necessary.
Checking the drive shaft
1. Check the drive shaft for bends or wear.
Replace if necessary.
Checking the lower case
1. Check the skeg and torpedo for cracks or
damage. Replace if necessary.
Assembling the lower case
1. Install the needle bearing into the lower
case to the specified depth. Bearing housing needle bearing remover 9
:
YB-06153
Needle bearing attachment 9
:
90890-06611
Driver handle 0
: YB-06071
Driver rod L3 0
: 90890-06652
S62Y6780
S62Y6785 
						

							62Y3A116-64
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ÈFor USA and Canada
ÉFor worldwide
NOTE:
Install the needle bearing with the manufac-
ture identification mark a
 facing upward.
When using the driver rod, do not strike the
special tool in a manner that will force the
stopper b
 out of place.
2. Install the sleeve, original shim(s), and
drive shaft bearing outer race.
ÈFor USA and Canada
ÉFor worldwide
CAUTION:
Add or remove shims, if necessary, when
replacing the pinion or lower case.
NOTE:
Apply the gear oil to the inside and outside
of the sleeve.
Install the sleeve by facing the projection d
forward. Driver handle 1
: YB-06071
Drive shaft needle bearing remover and 
installer 2
: YB-06155
Drive shaft needle bearing depth stop 3
:
YB-34473
Driver rod SL 4
: 90890-06602
Needle bearing attachment 5
:
90890-06611
Bearing depth plate 6
: 90890-06603
Depth c
: 186.4–188.6 mm (7.34–7.43 in)
Crank upper and lower seal installer 7
:
YB-06244
Bearing outer race attachment 7
:
90890-06626
Driver handle 8
: YB-06071
Driver rod LL 8
: 90890-06605
Drive shaft and lower case (T50/FT50B, FT50C) 
						

							LOWRLower unit
6-6562Y3A11
3. Install the original shim(s) and taper roller
bearing outer race.
ÈFor USA and Canada
ÉFor worldwide
CAUTION:
Add or remove shims, if necessary, when
replacing the forward gear or lower case.
Assembling the forward gear
1. Install the new taper roller bearing into
the forward gear using a press.
ÈFor USA and Canada
ÉFor worldwide
2. Install the new needle bearing into the
forward gear to the specified depth.
Forward gear bearing cup installer 9
:
YB-06276-B
Driver handle 0
: YB-06071
Bearing outer race attachment A
:
90890-06621
Driver rod LL B
: 90890-06605
Forward gear needle bearing and tapered 
roller bearing installer 1
: YB-06200
Bearing inner race attachment 2
:
90890-06662
Bearing housing needle bearing remover 3
:
YB-06112
Needle bearing attachment 3
:
90890-06614
Driver handle 4
: YB-06071
Driver rod L3 4
: 90890-06652
Depth 
a: 1.1 mm (0.04 in) 
						

							62Y3A116-66
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Assembling the drive shaft
1. Install the new drive shaft bearing into
the drive shaft using a press.
ÈFor USA and Canada
ÉFor worldwide
NOTE:
Use the special service tool or a general pipe
with the specified measurements.
Installing the drive shaft
1. Install the forward gear, then the drive
shaft assembly, pinion, and pinion nut,
and then tighten the nut to the specified
torque.
Installing the lower unit
1. Set the gearshift to the neutral position at
power unit and lower unit.
General pipe 1
:
D = 38 mm (1.49 in), d = 32 mm (1.26 in)
Bearing inner race attachment 2
:
90890-06643
Drive shaft holder 1
: YB-06049
Drive shaft holder 4 1
: 490890-06518
Pinion nut holder 2
: 90890-06505
Socket adapter 2 3
: 90890-06507
Pinion nut: 95 N·m (9.5 kgf·m, 68 ft·lb)
S62Y6505
N
Drive shaft and lower case (T50/FT50B, FT50C) 
						

							LOWRLower unit
6-6762Y3A11
2. Install the two dowel pins 1
 to the lower
unit.
3. Install the lower unit to the upper case,
and then tighten the bolts to the specified
torque.
4. Install the trim tab 2
 to its original posi-
tion, and then connect the speedometer
hose 3
.5. Install the propeller and propeller nut,
tighten the nut finger tight. Place a block
of wood between the anti-cavitation plate
and propeller to keep the propeller from
turning, and then tighten the nut to the
specified torque.
Mounting bolt: 40 N·m (4.0 kgf·m, 29 ft·lb) 
						

							62Y3A116-68
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 WARNING
Do not hold the propeller with your hands
when loosening or tightening it. Be sure
to remove the battery leads from the bat-
teries and the engine shut-off switch. Put
a block of wood between the cavitation
plate and propeller to keep the propeller
from turning.
NOTE:
If the grooves in the propeller nut 4
 do not
align with the cotter pin hole, tighten the nut
until they are aligned.
Propeller nut 4
:
35 N·m (3.5 kgf·m, 25 ft·lb)
Drive shaft and lower case (T50/FT50B, FT50C) 
						

							LOWRLower unit
6-6962Y3A11
Shimming (T50) (for USA and Canada)6 
						

							62Y3A116-70
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Shimming
NOTE:
Shimming is not required when assembling
the original lower case and inner parts.
Shimming is required when assembling the
original inner parts and a new lower case.
Shimming is required when replacing the
inner part(s).
Selecting the pinion shims
1. Calculate the specified value (M0) as
shown in the examples below.
NOTE:
“P” is the deviation of the lower case dimen-
sion from standard. 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 unreadable, assume that “P” is zero
and check the backlash when the unit is
assembled.
Example:
If “P” is “+5”, then
M0 = 0.20 + (+5)/100 mm = 0.20 + 0.05 mm
= 0.25 mm
If “P” is “–5”, then
M0 = 0.20 + (–5)/100 mm = 0.20 – 0.05 mm
= 0.15 mm
2. Install the drive shaft and drive shaft
bearing 1
 to the shim selecting tools.
3. Attach the clamp 2
 to the gauge base
using four bolts of appropriate sizes.
NOTE:
Install the shim selecting tools to the drive
shaft so that the shaft is at the center of the
hole.
4. Install the pinion and pinion nut, and then
tighten the nut to the specified torque.
Specified value (M0) = 0.20 + P/100 mm
Pinion shim selecting tools:
YB-34432-9 3
, YB-34432-10A 4
, 
YB-34432-11A 5
, YB-34432-17 2
 
Pinion nut: 95 N·m (9.5 kgf·m, 69 ft·lb)
Shimming (T50) (for USA and Canada) 
						

							LOWRLower unit
6-7162Y3A11
5. Measure the clearance (M) between the
shim selecting tool and the pinion as
shown.
NOTE:
Measure the pinion at three points to find the
clearance average.
6. Select the pinion shims (T3).
NOTE:
The sum of T3 and M should not be more
than M0.
Selecting the forward gear shims
1. Calculate the specified value (M0) as
shown in the examples below.
NOTE:
“F” is the deviation of the lower case dimen-
sion from standard. The “F” mark a
 is
stamped on the trim tab mounting surface of
the lower case in 0.01 mm units. If the “F”
mark is unreadable, assume that “F” is zero
and check the backlash when the unit is
assembled.
Example:
If “F” is “+5”, then
M0 = 1.70 + (+5)/100 mm = 1.70 + 0.05 mm
= 1.75 mm
If “F” is “–5”, then
M0 = 1.70 + (–5)/100 mm = 1.70 – 0.05 mm
= 1.65 mm
Pinion shim thickness (T3) = M0 – M
Available shim thicknesses:
0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and 
0.50 mm
Specified value (M0) = 1.70 + F/100 mm