Echo 77412 Owners Manual v.3 - Manual (Page 24)

Crary Bear Cat Owners Manual 22
SERVICE & MAINTENANCE
BEFORE INSPECTING OR SERVICING ANY PART OF THIS MACHINE, SHUT OFF POWER SOURCE,
DISCONNECT SPARK PLUG WIRE FROM SPARK PLUG AND MAKE SURE ALL MOVING PARTS HAVE COME TO A COMPLETE STOP.
WARNING
5.7 REPLACING ROTOR BEARINGS.
5.7.1 ELECTRIC/RECOIL MODELS
REMOVING THE OLD BEARINGS
1. Move the chipper engagement lever to the start position.
2. Shut engine off.
3. Disconnect battery cables.
4. Remove the belt guard. Two 5/16" x 1" bolts are located on
each side of the belt guard.
5. Remove the idler pulley.
6. Move the chipper engagement lever to the chipping posi-
tion.
7. For models 77412 and 77412S, the belt guard will have to
be removed. To do this, remove the 1/2" bolt attaching the
belt guide to the rotor bearing and the 5/16" bolt attaching
the belt guide to the engine.
8. Remove the belt.
9. To remove the rotor sheave, do the following:
9a. Remove the three bolts securing the rotor sheave to the
rotor shaft.
9b. Reinstall the bolts into the second set of holes. Gradu-
ally tighten both bolts equally to push the sheave off
the rotor shaft.
10. To remove the front bearing, do the following:
10a. Remove the snap ring.
10b. Loosen the setscrews securing the front bearing to the
rotor shaft.
10c. Remove the two 1/2" x 1-1/2" bolts and 1/2" centerlock
nuts holding the front bearing to the chipper housing.
10d. Remove shims located between the bearing and the
chipper housing (if applicable).
10e. Slide the front bearing off the rotor shaft.
10f. Remove the second snap ring.
11. To remove the back bearing do the following:
11a. Remove the seven 5/16" nylock nuts and washers se-
curing the disk cover to the chipper housing. Remove
the disk cover.
11b. Loosen the setscrews securing the back bearing to
the rotor shaft.
11c. Remove the two 1/2" x 1-1/2" bolts and 1/2" center-
lock nuts holding the back bearing to the chipper
housing.
11d. Slide the chipper disk out from the chipper housing
until the bearing slides off the rotor shaft.
INSTALLING THE NEW BEARINGS
Slide the chipper disk into the chipper housing.
As the rotor shaft slides through the hole in the chipper hous-
ing, slide the new back bearing onto the rotor shaft.
Tighten the two 1/2" x 1-1/2" bolts and 1/2" centerlock nuts
securing the back bearing to the chipper housing. Torque
to 75 Ft-lb.
Slide a snap ring, shims (if applicable), front bearing and
another snap ring onto the rotor shaft.
Tighten the two 1/2" x 3/4" bolts and nuts securing the front
bearing to the chipper housing.
Tighten the two setscrews located on both the front and back
bearings securing the bearings to the rotor shaft.
Replace the rotor sheave and tighten the three bolts into the
correct holes to secure the sheave to the rotor shaft.
Ensure the chipper engagement lever is in the chipping
position
Replace the belt. Using a straight edge, check the belt
alignment. The rotor sheave and the engine sheave must
be flush.
For models 77412 and 77412S, reinstall the belt guide.
Move the chipper engagement lever to the start position and
reinstall the idler pulley.
Reinstall the disk cover using seven 5/16" nuts and wash-
ers.
Replace the belt guard and resume operation.
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WARNING
It is extremely important to slide the disk assembly forward
to remove any existing play in the disk assembly. Failure to
do so could result in the chipper blades striking the chipping
anvil which could result in serious injury or death.