Section 5: Maintenance & Lubrication
11/2/18
31
Remove cutting blades and sharpen or replace as
follows:
3. Remove rubber plug (#5) above cutter blade (#6).
Rotate blade bolt (#1) until in alignment with access
hole (A).
4. Unscrew locknut (#3) to remove cutting blade (#6).
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. Do not weld on blades.
g. 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 5-2 on page 31:
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
.
7.
Insert keyed blade bolt (#1) through blade (#6),
keyed hole in dishpan (#4), and flat washer (#2).
Secure blade with a
new locknut (#3)
and torque
locknut to 450 ft-lbs.
8. If replacing dishpan (#4), nut (#7) on gearbox output
shaft should be torqued to 450 ft-lbs minimum and
secured with cotter pin (#8) with both legs bent
opposite directions around the nut.
9. Replace rubber plug (#5).
10. Reconnect main driveline to the tractor.
IMPORTANT:
Examine blade bolts and their flat
washers for excessive wear and replace if worn.
IMPORTANT:
Locknuts can lose their ability to lock
properly once removed. Always use a new locknut
when installing blades.
Cutter Blade Assembly (Right Wing Shown)
Figure 5-1
Blade Rotation
Figure 5-2
35135
Use 1-11/16" Socket
Wrench On Blade Nut (#3)
Blade Bolt Kit & Dishpan Part No’s.
Item Part No.
Part Description
318-586A BLADE BOLT KIT (Item No’s 1, 2, & 3)
)
1
802-277C BLADE BOLT 1 1/8-12 x 3 7/16 WITH KEY
2
804-147C WASHER FLAT 1 HARD ASTMF436 PN
3
803-170C NUT HEX TOP LOCK 1 1/8-12 PLATE
4
331-068H WELDMENT DISHPAN
5
840-273C PLUG LP 3" ID RUBBER
6
820-112C CUTTER BLADE 1/2 x4x25 CW (LH Wing)
6
820-137C CUTTER BLADE 1/2 x3x25 CCW (RH Wing)
6
820-138C CUTTER BLADE 1/2 x3x31 CCW (CTR Deck)
CCW
CCW
CW