Craftsman 107.289920 - Manual (Page 25)

CLEAN DECK &
CHECK / REPLACE MOWER BLADES
Service Interval: 25 hours or as required.
A
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.
A
WARNING
For your personal safety, blade mounting
capscrews must each be installed with a spring
washer, then securely tightened. Torque blade
mounting capscrew to 45-55 ft-lbs (61-75 Nm).
1. Remove mower deck (see “Mower Deck Removal” in
the OPERATION section).
2. Remove blade to inspect it or to safely access the
underside of the mower deck (see Figure 24). Use a
block of wood to prevent blade rotation while loosen­
ing the capscrew by turning it counterclockwise.
3. Remove the capscrew (A, Figure 25), spring 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 dam­
aged, it must be replaced.
6. Balance the blade as shown in Figure 26. 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 (C, Figure 25)
pointing up toward the mower deck as shown.
8. Reinstall the spring washer (B) and capscrew (A).
Use a wooden block (B) to prevent blade rotation
while tightening the capscrew (A) to 45-55 ft-lbs (61­
75 Nm). Turn capscrew clockwise to tighten.
Figure 24. Blade Removal
Figure 25. Blade Installation
A. Blade Capscrew
B. Spring Washer
C. Lift Wings
D. 4x4 Wood Block
Figure 26. Balancing the Blade
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