Mercury 100 FourStroke, Service Manual

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90-830234R3 DECEMBER 1997 LOWER UNIT - 6A-13
13. Replace cam follower if worn or pitted.
14. Replace sliding clutch if jaws are rounded or
chipped. Rounded jaws indicate one or more of
the following:
a. Improper shift cable adjustment.
b. Engine idle speed too high while shifting.
c. Shifting from neutral to reverse (or forward)
too slowly.
f
d
e
f
c
b
a
51265
a - Cam Follower
b - 3 Metal Balls
c - Guide Block
d - Spring
e - Sliding Clutch
f - Jaws
15. Check bearing surfaces of propeller shaft for pit-
ting or wear. If shaft is worn or pitted, replace
shaft and corresponding bearing.
16. Replace propeller shaft if any of the following ex-
ist:
a. Splines are twisted or worn.
b. Oil seal surface is grooved.
c. Shaft has a noticeable “wobble” or is bent
more than 0.009 in. (0.23mm). Prop shaft
trueness should be measured with a dial indi-
cator with prop shaft on V-blocks.
b
b
c
a
51877
a - V-Blocks
b - Bearing Surfaces
c - Measure with Dial Indicator at This Point
Pinion Gear, Drive Shaft, and
Forward Gear
Model Drive Shaft Holding Tool
50 Bigfoot (4-Stroke) 91-56775
60 Bigfoot 91-817070
75/90/100/115/125 91-56775
1. Hold drive shaft using Drive Shaft Holding Tool
(91-56775); remove (and discard) pinion nut.
2. Remove drive shaft, pinion gear, bearing and for-
ward gear.
3. Replace pinion gear if it is chipped or worn.
4. Replace bearing and race if either are rusted or
damaged; or if bearing does not roll freely. To re-
move race, refer to “Lower Drive Shaft Bearing
Race,” following.
5. Replace forward gear if gear teeth or clutch teeth
are chipped or worn.
f
b
d
e
c
a
19175
a - Drive Shaft Holding Tool (91-56775)
b - Pinion Nut
c - Drive Shaft
d - Pinion Gear
e - Bearing
f - Forward Gear