Craftsman CX Series Operator's Manual page 17

Blade Care
When removing the cutting blade for sharpening or replacement, protect
your hands with a pair of heavy gloves or use a heavy rag to hold the blade.
Periodically inspect the blade adapter for cracks, especially if you strike a foreign
object. Replace when necessary. Follow the steps below for blade service.
1. Disconnect spark plug boot from spark plug. Turn mower on its side making
sure that the air filter and the carburetor are facing up.
2. Remove the bolt and the blade bell support which hold the blade and the
blade adapter to the engine crankshaft. See Figure 19.
3. Remove blade and adapter from the crankshaft.
4. Remove blade from the adapter for testing balance. Balance the blade on a
round shaft screwdriver to check. Remove metal from the heavy side until
it balances evenly. When sharpening the blade, follow the original angle of
grind. Grind each cutting edge equally to keep the blade balanced.
An unbalanced blade will cause excessive vibration when rotating at high
speeds. It may cause damage to mower and could break causing personal
injury.
SERVICE AND MAINTENANCE
Figure 18
WARNING
WARNING
Blade Bell Support
5. Lubricate the engine crankshaft and the inner surface of the blade adapter
with light oil. Slide the blade adapter onto the engine crankshaft. Place the
blade on the adapter such that the side of the blade marked "Bottom" (or
with part number) faces the ground when the mower is in the operating
position. Make sure that the blade is aligned and seated on the blade adapter
flanges. See Figure 19 inset.
6. Place blade bell support on the blade. Align notches on the blade bell
support with small holes in blade.
7. Replace hex bolt and tighten hex bolt to torque: 450 in. lbs. min., 600 in. lbs.
max.
To ensure safe operation of your mower, periodically check the blade bolt for correct
torque.
17
Blade
Adapter
Blade
Bolt
Figure 19