Land Pride RC5020 Series Operator's Manual - page 33
31
Section 5: Maintenance & Lubrication
4/25/12
RC5020 (540 RPM) and RCM5020 (1000 RPM) Rotary Cutters 318-474M
Table of Contents
Refer to Figure 5-2:
3.
Remove wing nuts (#12), lock washers (#11), flat
washer (#10)and access cover (#7). Rotate blade
bolt (#1) until in alignment with access hole (A).
4.
Unscrew locknut (#6) to remove cutting blade (#3).
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.
Blade Rotation (Rear of Cutter Shown)
Figure 5-1
Refer to Figure 5-1:
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. Airfoil (lift) must be
oriented towards the top of deck.
Refer to Figure 5-2:
CW
CCW
CCW
IMPORTANT: Shim (#2) may or may not be
required. The shim is not used if blade deflection is
less than 3/4". A shim is required if blade deflection
is greater than 3/4".
IMPORTANT: Locknuts can lose their ability to lock
properly once removed. Therefore, always use a
used blade nut or plain nut in steps 7 & 8 and then
replace used nut with new locknut in step 9.
Cutter Blade Assembly
Figure 5-2
7.
Start by assembling blades without shim (#2). Insert
blade bolt (#1) through blade (#3), dish pan (#4) and
flat washer (#5). Temporarily secure blade with a
used 1 1/8"-12 nut. Draw nut up snug. Do not
tighten.
8.
Check blade deflection. If deflection is greater than
3/4", remove blade bolt and reassemble as before
except include shim (#2) when reassembling. Select
shim thickness based on deflection. The greater the
deflection, the thicker the shim.
9.
Once blade deflection is correct, replace used nut
with new locknut (#6) and torque to 450 ft. lbs.
10. If replacing blade carrier (#13), 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 the nut.
11. Replace access cover (#7) with flat washers (#10),
lock washers (#11) and wing nuts (#12).
12. Reconnect main driveline to tractor PTO shaft.
3/4" maximum
blade deflection
when blade
bolts are tight
26675
13
Use 1-11/16"
Socket Wrench
On Blade Nut #6
Land Pride Cutter Blade Parts
Item Part No.
Part Description
318-586A
BLADE BOLT KIT (Item No’s 1, 2, 5 & 6)
)
1
802-277C
BLADE BOLT 1 1/8-12 x 3 7/16 WITH KEY
2
312-075D
BLADE SPACER 16 GA. (.06")
2
312-082D
BLADE SPACER 18 GA. (.062")
2
312-089D
BLADE SPACER 20 GA. (.036")
2
312-808D
BLADE SPACER 24 GA. (.024")
3
820-168C
CUTTER BLADE 1/2 x 4 x 29 CCW
3
820-249C
CUTTER BLADE 1/2 x 4 x 29 CW
4
330-399D
WELDMENT DISHPAN
5
804-147C
WASHER FLAT 1 HARD ASTMF436
6
803-170C
NUT HEX TOP LOCK 1 1/8-12 PLATE
7
312-812D
ACCESS COVER PLATE
IMPORTANT: Examine blade bolts (#1) and
washers (#5) for excessive wear and replace if worn.