Craftsman 12A-764M799 Operator's Manual page 19

SeRviCinG The CuTTinG bLAdeS
WARninG
Be sure to shut the engine off and disconnect the spark plug wire
and ground against the engine to prevent unintended starting before
removing the cutting blade(s) for sharpening or replacement. Protect
your hands by using heavy gloves or a rag to grasp the cutting blade.
WARninG
Periodically inspect the blade spindles for cracks or damage, espe-
cially if you strike a foreign object. Replace immediately if damaged.
WARninG
Mower blades are sharp. When working near blades, wear heavy
leather gloves or wrap blades in thick rags to protect yourself from
the sharp edges.
blade Removal
1. Remove the deck from beneath the mower and gently flip the
deck over to expose its underside. Refer to "Removing the Mower
Deck" for instructions.
2. Place a 2x4 block of wood approximately 8.5" long between the
deck housing and the cutting blade to act as a stabilizer,
Figure 20.
3. Remove the hex flange nut that secures the blade to the spindle
assembly, Figure 20.
blade Sharpening
IMPORTANT: If any metal separation is present, replace the blades
with new ones.
1. To properly sharpen the cutting blades, remove equal amounts
of metal from both ends of the blades along the cutting edges,
parallel to the trailing edge, at a 25° to 30° angle, Figure 21.
a. It is important that each cutting blade edge be ground
equally to maintain proper blade balance. A poorly balanced
blade will cause excessive vibration and may cause damage
to the mower and result in personal injury. The blade can be
tested by balancing it on a round shaft screwdriver. Grind
metal from the heavy side until it balances evenly.
blade installation
1. When installing a blade, place the side of the blade with a part
number stamped in it facing the ground when the mower is in the
operating position.
2. Use a torque wrench to tighten the spindle flange nut to between
70-90 foot-pounds.
SERVICE AND MAINTENANCE
Use block of wood to stabilize blade.
1
Remove flange nut to release blade
Figure 20
Figure 21