Craftsman 107.28791 Operator's Manual page 20

CLEAN DECK &
CHECK / REPLACE MOWER BLADES
Service Interval: 25 hours or as required.
WARNING
For your personal safety, do not handle the sharp
mower blades with bare hands. Careless or
improper handling of blades may result in serious
injury.
WARNING
For your personal safety, blade mounting
capscrews must each be installed with a
hex/spline washer and spring washer, then
securely tightened. Torque blade mounting
capscrew to 45 - 55 ft. lbs. (61 - 75 N.m.)
1. Remove mower deck (see "Mower Deck Removal" in
the OPERATION section).
2. See Figure 20. Remove blade to inspect it or to
safely access the underside of the mower deck. Use
a block of wood to prevent blade rotation while
loosening the capscrew by turning it
counterclockwise.
3. Remove the capscrew (D, Figure 22), spring washer
(C), hex washer (B), and blade.
4. Clean the underside of the mower deck.
5. Inspect the blades for nicks or dull edges. Use a file
to sharpen blade to a fine edge. If the blade is
damaged, it must be replaced.
6. Balance the blade as shown in Figure 21. Center the
blade's hole on a nail lubricated with a drop of oil. A
balanced blade will remain level. If the blade is not
balanced, continue to sharpen the heavy side until it
balances.
7. Reinstall the blade with the lift wings (E, Figure 22)
pointing up toward the mower deck as shown.
8. Reinstall the hex washer (B, Figure 22), spring
washer (C) and capscrew (D). Use a wooden block
(A) to prevent blade rotation while tightening the
capscrew (D) to 45-55 ft. lbs. (61-75 N.m). Turn
capscrew clockwise to tighten.
Figure 20. Blade Removal
Workbench
Figure 21. Balancing The Blade
A
Figure 22. Blade Installation
A. 4x4 Wood Block
B. Hex Washer
C. Spring Washer
D. Blade Capscrew
E. Lift Wings
20
LOOSEN
Nail
B
E
C
D