Craftsman 247.77586 Owner's Manual page 15

2. SHARPENING OR REPLACING
THE BLADES
Chipper Blades
Disconnect spark plug wire and move it away
from spark plug.
Remove the flail screen as instructed in
previous section.
Using a 1/2" wrench, remove the chipper chute
by removing three hex nuts and washers. See
figure 17.
Using a 7/16" wrench, remove the brace
(holding the chute to the frame) by removing the
hex bolts.
NOTE: When re-assembling, the cupped washer
goes on the slot toward the bottom of the chipper
chute with the cupped side against the chute.
Rotate the impeller assembly by hand until you
locate one of the two chipper blades in the
chipper chute opening. Remove the blade, using
a 3/16" allen wrench on the outside of the blade
and 1/2" wrench on the impeller assembly
(inside the housing). See figure 18.
o
Sharp Edge
Figure 18
Remove the other blade in the same manner.
Replace or sharpen blades.
If sharpening, make certain to remove an equal
amount from each blade.
Reassemble in reverse order. Make certain
blades are reassembled with the sharp edge
facing the direction shown in figure 18 (sharp
edge is assembled toward the slotted opening at
the bottom).
Torque bolts and nuts to 250-350 inch-pounds.
Shredding Blade
The shredding blade may be removed for sharpening
or replacement as follows.
• Disconnect spark plug wire and move it away
from spark plug.
• Lower the hopper assembly. Block up the
housing. See figure 19.
Allen
Screws
f
Pipe
Blade
Wrench
Figure 19
• Remove the six hex lock nuts and lock washers
from the housing weld bolts using a 1/2" wrench.
Separate the chipper-shredder into two halves.
• Remove the back-up plate.
NOTE: When reassembling, make certain the
embossed tab faces inward towards the impeller, and
opening on the back-up plate is toward the bottom of
the unit.
Remove the two hand knobs and cupped
washers which secure the chute deflector. Raise
the chute deflector.
Insert a 1/2" or 3/4" diameter pipe through the
flail screen into the impeller to keep it from
turning, or remove the flail screen and insert a
piece of wood (2 x 4) into the chute opening.
Remove the two outside screws on the blade,
using a 3/16" allen wrench and a 1/2" wrench.
Remove the blade by removing the center bolt,
lock washer and flat washer.
_ WARNING: Use caution when removing
the blade to avoid contacting the weld bolts
on the housing.
When sharpening the blade, follow the original
angle of grind as a guide. It is extremely
important that each cutting edge receives an
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