The information in this section is written for dealer service personnel. The
repair described here requires special skills and tools. If your shop is not prop-
erly equipped or your mechanics are not properly trained in this type of repair,
you may be time and money ahead to replace complete assemblies.
WARNING
Before working underneath, read manual instructions, securely
block up, and check stability. Secure blocking prevents equipment from
dropping due to hydraulic leak down, hydraulic system failure, or
mechanical component failure.
Keep all persons away from operator control area while performing
adjustments, service, or maintenance.
Always wear relatively tight and belted clothing to avoid getting
caught in moving parts. Wear sturdy, rough-soled work shoes and protec-
tive equipment for eyes, hair, hands, hearing, and head; and respirator or
filter mask where appropriate.
GEARBOX MAINTENANCE
NOTE: Read this entire section before starting any repair. Many steps
are dependent on each other.
1. Fill gearbox with SAE 80W or 90W gear lube. Proper oil level is between
lowest ring and end of dipstick.
NOTE: Repair to this gearbox is limited to replacing bearings, seals, and
gaskets. Replacing gears, shafts, and a housing is not cost effective. Pur-
chasing a complete gearbox is more economical.
2. Inspect gearbox for leakage and bad bearings. Leakage is a very serious
problem and must be corrected immediately.
NOTE: Bearing failure is indicated by excessive noise and side-to-side or
end-play in gear shafts.
Seal Replacement (Figure 11)
Recommended sealant for gearbox repair is Permatex
Gasket or equivalent.
Leakage can occur at the vertical or horizontal gaskets and shaft seals.
Leakage at the horizontal gasket or seal can be repaired without removing the
gearbox from the cutter.
Seal Installation
NOTE: Proper seal installation is important. An improperly installed seal
will leak.
1. Clean area in housing where seal outer diameter (OD) seats. Apply a thin
coat of Permatex.
2. Inspect area of shaft where seal seats. Remove any burrs or nicks with
an emery cloth.
3. Lubricate gear shaft and seal lips.
4. Place seal squarely on housing, spring-loaded lip toward housing. Select
a piece of pipe or tubing with an OD that will sit on the outside edge of the
20 Dealer Service
DEALER SERVICE
CAUTION
CAUTION
®
Aviation 3D Form-A-
seal but will clear the housing. Tubing with an OD that is too small will
bow seal cage and ruin seal.
5. Carefully press seal into housing, avoiding distortion to the metal seal
cage.
1. Seal
2. Pipe or tube
3. Seal seat
4. Casting
Pipe or tube must press at
outer edge of seal.
Incorrect
Installation
Figure 11. Seal Installation
Vertical Shaft Seal Replacement (Figure 12)
1. Disconnect and remove the rear driveline from the gearbox.
2. Remove drain plug and drain gear lube from housing. Replace plug when
empty.
3. Remove crossbar (see page 23).
4. Remove protective seal (8) and vertical shaft seal (18). Replace seal (18)
with new seal.
5. Vertical seal should be recessed in housing. Horizontal seal (19) should
be pressed flush with outside of housing.
NOTE: Distortion to seal cage or damage to seal lip will cause seal to
leak.
6. Fill gearbox with SAE 80W or 90W gear lube until it runs out the level
plug.
7. Remove and replace any seal damaged in installation.
Horizontal Shaft Seal Replacement (Figure 12)
1. Disconnect and remove the rear driveline from the gearbox.
2. Remove drain plug and drain gear lube from housing. Replace plug when
empty.
3. If the leak occurred at either end of horizontal shaft, remove oil cap (20)
and/or oil seal (19). Replace with new one.
4. Fill gearbox with SAE 80W or 90W gear lube to proper level.
GEARBOX REPAIR
Removal from Cutter (Figure 12)
NOTE: Gearbox is heavy: do not attempt to move without mechanical
assistance.
1. Disconnect and remove the rear driveline from the gearbox.
2. Remove cotter pin and nut from vertical shaft and remove crossbar (see
page 23).
3. Remove the six bolts that attach gearbox to cutter and remove gearbox.
Disassembly (Figure 12)
1. Remove top cover (22) from gearbox and pour out gear oil.
2. Remove oil cap (20) (to be replaced).
3. Remove snap ring (10) and shim (13) from input shaft (3).
4. Support gearbox in hand press and push on input shaft (3) to remove
bearing (7).
5. Remove six cap screws (23) and top cover (22) from housing. Remove
gear (1) from inside housing.
6. Remove oil seal (19) from front of housing (to be replaced).
7. Remove snap ring (10) and shim (13) from front of housing (2).
8. Remove input bearing (7) by using a punch and hammer from outside of
housing.
9. Support housing in vise in a horizontal position.
10. The castle nut (15), cotter pin (25), and hub are already removed with the
stump jumper/crossbar. Remove the protective seal (8), and oil seal (18).
11. Remove cotter pin (9), castle nut (14), and shim (17) from output shaft
(4).
12. Remove output shaft (4) by using a punch and hammer and tap on top to
drive down. Remove gear (5) and shim (16) from inside housing.
13. Remove bottom bearing (26) by using a punch and hammer from the top,
outside the housing.
MAN1246 (04/10/2018)