Blade Servicing - Oregon 480RC Original Instruction Manual

OWNER SERVICE

Blade Servicing

Blade Removal (Figure 11)
NOTICE
• When sharpening blades, grind the same amount
on each blade to maintain balance. Replace blades
in pairs. Unbalanced blades will cause excessive
vibration, which can damage gearbox bearings.
Vibration may also cause structural cracks to cutter.
• If blade pin is seized in crossbar and extreme force
will be needed to remove it, support crossbar from
below to prevent gearbox damage.
1. Disconnect driveline from tractor PTO.
2. Raise cutter and block securely (see Blocking Method,
page 18).
3. Align crossbar (1) with blade access hole in the cutter
frame. Remove blade pin nut (5) and lock washer (4).
Carefully drive pin (3) out of crossbar.
4. Rotate crossbar (8) and repeat for opposite blade.
Figure 11. Blade Assembly
20
1. Crossbar
2. Blade
3. Blade pin
4. Lock washer
5. 1-1/8 NF Jam nut
Blade Installation (Figure 11)
CAUTION
• Your dealer can supply genuine replacement blades.
Substitute blades may not meet original equipment
specifications and may be dangerous.
• Crossbar rotation is counterclockwise when looking
down on cutter. Be sure to install blade cutting edge
to lead in counterclockwise rotation.
1. Inspect blade pin (3) for nicks or gouges, and if you find
any, replace the blade pin.
2. Insert blade pin through the blade (2). Blade should swivel
on blade pin; if it doesn't, determine the cause and correct.
3. Align crossbar (1) with blade access hole in cutter frame.
Apply a liberal coating of Never Seez® or equivalent to
blade pin and crossbar hole. Make sure blade offset is
away from cutter. Push blade pin through crossbar.
4. Insert lock washer (4) and nut (5) through blade access
hole in deck. Install on blade pin (3) and tighten to 450 lb-ft
using a 1-11/16" socket.
NOTE: Blade should be snug but should swivel on pin
without having to exert excessive force.
Blade Sharpening (Figure 12)
1. Sharpen both blades at the same time to maintain balance.
Follow original sharpening pattern.
2. Do not sharpen blade to a razor edge—leave at least a
1/16" blunt edge.
3. Do not sharpen back side of blade.
Figure 12. Blade Sharpening