Mercury 40 Service Manual page 496

INSTALLATION
1. Grease the drive shaft, shear key, and impeller
bore. Place the plastic sleeve inside the impeller
and install impeller, shear key, shims nut retainer,
and impeller nut. Turn the nut tight on the shaft to
remove any play between the impeller and shaft.
If the tabs on the retainer do not line up with the
flats on the nut, remove the nut and turn the re-
tainer over and re-tighten the nut again.
a - Plastic Sleeve
b - Impeller
c - Shear Key
d - Shims
e - Nut Retainer
f - Impeller Nut
2. Temporarily reinstall the water intake housing in
order to check for impeller clearance. The clear-
ance between the impeller and liner should be
0.030 in. (0.8 mm). Shim washers can be trans-
ferred to either side of the impeller to raise or low-
er the impeller to the correct clearance setting.
The water intake housing can be shifted side
ways a small amount in order to center the liner.
6D-14 - LOWER UNIT
3. After setting the impeller height, tighten the im-
peller nut snug with a wrench. Secure impeller
nut by bending tabs against the flats on the impel-
ler nut.
a
a - Tabs
b
4. Reinstall the water intake housing with six bolts.
Check clearance around the impeller to make
sure the water intake housing is centered and not
c
rubbing against the liner. Torque mounting bolts
d
to 100 lb. in. (11.2 N·m).
e
NOTE: If the outboard is used in salt water, apply
f
Quicksilver Anti-Corrosion Grease around the entire
mounting flange on the water intake housing and also
to the threads on the six mounting bolts.
a
90-852572R1 JANUARY 1998