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
:...

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...

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...

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
:...

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...

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....

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...

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...

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...