Slip Clutch Adjustment; Driveline Shear Bolt Replacement - Oregon 480RC Original Instruction Manual

Slip Clutch Adjustment

The slip clutch is designed to slip so that the gearbox and
driveline are protected if the cutter strikes an obstruction.
A new slip clutch or one that has been in storage over the
winter may seize. Before operating the cutter, make sure it
will slip by performing the following operation:
1. Turn off tractor engine and remove key.
2. Loosen nuts on springs until the springs can rotate freely,
yet remain secure on the bolts.
3. Mark outer plates of slip-disc clutch as shown in
Figure 13.
4. Securely attach implement to the tractor and start the
tractor.
5. Engage PTO for several seconds then quickly disengage it.
6. Turn tractor off and remove key.
7. The friction lining plates should have "slipped". Check the
marks placed on the outer plates of the slip-disc clutch in
step 3 to make sure this is the case.
8. If clutch does not slip, check assembly for oil, grease and
debris. Clean if necessary.
9. Reassemble clutch and tighten bolts no more than 1/8 of a
turn at a time until desired setting of 1.26" is reached.
10. If excessive slippage continues, check lining plates for
excessive wear. They are 1/8" thick when new and should
be replaced after 1/32" of wear to ensure proper operation.
Figure 13. Slip Clutch Assembly

Driveline Shear Bolt Replacement

NOTICE
Always use approved 1/2" NC x 3" grade 2 shear bolt
as a replacement part. Using a hardened bolt or shear
pin may result in damage to driveline or gearbox.
1. Remove damaged shear bolt (7).
2. Rotate driveline (6) to align holes in yoke and shaft. Install
shear bolt and secure with lock nut (8).
1. Clutch shield
2. 5/16 NC x 3/4 Cap screw
3. 5/16 Lock washer
4. 5/16 Flat washer
5. Retaining ring
6. Shear bolt driveline
7. 1/2 NC x 3 Cap screw GR2
8. 1/2 NC Lock nut
Figure 14. Shear Bolt Driveline Assembly
OWNER SERVICE
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