JLG 20VP (3120728) Service Manual - Manual (Page 30)

SECTION 2 - SERVICE PROCEDURES
2-12 – JLG Lift – 3120728
Final Gear Box Assembly
1. If necessary, install a new drive shaft lip seal into the
drive shaft hole in the gear box housing before
assembling the drive shaft gear set into the gear
box. Install the seal so it is even with the bottom of
the chamfer in the drive shaft hole on the outside of
the housing and flush with the bearing seat on the
inside of the housing.
2. Lube the drive shaft seal with a thin film of oil before
sliding the drive shaft over the seal.
3. Position the gear box with open cover side up, allow
space under the gear box for the drive shaft to
extend through without obstruction.
4. Hold the gear and pinion, and drive shaft assembies
together with the pinion gear and the ring gear on
the drive shaft meshing. Now carefully slide these
assemblies into the gear box housing sliding the
drive shaft through the drive shaft lip seal.
NOTE: While assembling the gear assemblies into the gear
box housing, be careful with the drive shaft seal and
the softer brass worm gear and brass drive worm
gear from the drive motor.
5. Continue to drop the gear assemblies into the gear
box, align the bearings with the bearing seats in the
housing on both assemblies. Drop the gear and pin-
ion (smaller) bearing into it’s seat first, while wiggling
that gear set align the drive shaft bearing and wiggle
it into it’s seat. When both are seated continue to
next step.
6. With the gear box still positoned with the open cover
side up, fill the gear box with six (6) ounces (U.S.)
(175cc’s) of good quality worm gear oil (Specifica-
tion - SAE 90 weight - AGMA#5 - EP Compounded).
When pouring the gear oil, wet the gears and bear-
ings with the oil.
7. Wet with gear oil and place the large wave washer
on the end of the drive shaft bearing and the small
wave washer on the end of the gear and pinion bear-
ing.
8. Clean the mating surfaces of the side cover and the
gear box and check that the cover dow guide pins
are properly installed in the cover.
9. On older model gear boxes apply sealant to the
cover mating surface on the gear box. On newer
model gear boxes insert the rubber seal into the
groove in the cover.
10. Using the cover dow guide pins, place the cover
onto the gear box housing.
11. Secure using the four (4) hex cap screws, torque
screws evenly to 90 in. lbs.
12. Install the drive motor back onto the machine.
Figure 2-10. Drive Shaft Assembly.
SIDE PROFILE
SPACER
PINION GEAR KEY
DRIVE SHAFT
PINION
GEAR
42mm x 20mm x 14mm
BEARING
42mm x 25mm x 12mm
BEARING