Section 5: Maintenance & Lubrication
7/30/20
RC4614 & RCM4614 Rotary Cutters 331-937M
42
Cutter Blade Maintenance
DANGER
!
To avoid serious injury or death:
•
Always disconnect driveline from the tractor and secure
implement in the up position with solid, non-concrete
supports before servicing the underside. A person can
become entangled in the drivetrain if the tractor is started
and power take-off is engaged or crushed by an
•
Always secure equipment with solid, non-concrete supports
before working under it. Never go under equipment
supported by concrete blocks or hydraulics. Concrete can
break, hydraulic lines can burst, and/or hydraulic controls
can be actuated even when power to hydraulics is off.
WARNING
!
To avoid serious injury or death:
•
Wait for blades to come to a complete stop before accessing
blade bolts through blade bolt access hole.
•
Do not operate cutter with blades that are out-of-balance,
bent, excessively worn, excessively nicked, or with blade
bolts that are excessively worn. Such blades can break loose
•
Do not attempt to straighten a bent blade or weld on a
blade. Do not attempt to modify a blade such as hard
surfacing, heat treating, cold treating, or by any other
method. Always replace blades with genuine OEM blades to
•
Wear eye protection and gloves while inspecting, removing,
sharpening, and replacing a blade.
Always inspect cutting blades before each use. Make
certain they are properly installed and in good working
condition. Replace any blade that is damaged, worn,
bent, or excessively nicked. Never try to straighten a bent
blade! Small nicks can be ground out when sharpening.
Remove cutting blades and sharpen or replace as
follows:
1. Place tractor gear selector in park and/or set brakes,
shut engine off and remove ignition key.
2. Disconnect main driveline from tractor and secure
cutter deck in the up position with solid supports
before servicing underside of cutter.
IMPORTANT:
Cutting blades must be replaced in
mating pairs. Not replacing both blades will result in
an out-of-balance condition that will contribute to
premature bearing breakdown on the spindle hub
and create structural cracks in the cutter housing.
Refer to Figure 5-2 on page 43:
3. Remove rubber plug (#6) above cutter blade (#7).
Rotate blade bolt (#1) until in alignment with access
hole (A).
4. Unscrew locknut (#3) to remove cutting blade (#7).
Blade bolt (#1) is keyed and will not turn freely.
5. Both blades should be sharpened at the same angle
as the original cutting edge and must be replaced or
re-ground at the same time to maintain proper
balance in the cutting unit. The following precautions
should be taken when sharpening blades:
a. Do not remove more material than necessary.
b. Do not heat and pound out a cutting edge.
c. Do not grind blades to a razor edge. Leave a blunt
cutting edge approximately 1/16" thick.
d. Always grind cutting edge so end of blade remains
square to cutting edge and not rounded.
e. Do not sharpen back side of blade.
f. Both blades should weigh the same with not more
than 1 1/2 oz. difference. Unbalanced blades will
cause excessive vibration which can damage
gearbox bearings and create structural cracks.
Refer to Figure 5-3 on page 43:
6. Carefully check cutting edges of blades in relation to
blade carrier rotation to ensure correct blade
placement. Cutter blades must be installed with
cutting edge leading in rotation
.
Refer to Figure 5-2 on page 43:
WARNING
!
To avoid serious injury or death:
Locknuts can lose their ability to lock properly once removed.
Always use a new locknut when installing blades.
7. Insert blade bolt (#1) through cutter blade (#7),
dishpan (#4), blade carrier (#5), and flat washer (#2).
Secure blade with a new 1 1/8"-12 hex top lock
nut (#3). Torque locknut to 450 ft-lbs.
8. Replace rubber plug (#6).
9. If replacing dishpan (#4) and/or blade carrier (#5),
nut (#8) on gearbox output shaft should be torqued to
550 ft-lbs minimum and secured with cotter pin (#9)
with both legs bent opposite directions around nut.
10. Reconnect main driveline to the power take-off shaft
and remove support blocks.
IMPORTANT:
