JLG 1230ES Service Manual - Manual (Page 48)

SECTION 4 - BASE COMPONENTS
4-12 – JLG Lift – 3121222
Roll And Leak Testing
Torque-Hub units should always be roll and leak tested
before disassembly and after assembly to make sure that
the unit's gears, bearings and seals are working properly.
The following information briefly outlines what to look for
when performing these tests.
NOTE: The brake must be released before performing the roll test.
This can be accomplished by supplying 24 Volts D.C. to the
gray 2-pin brake connector.
The Roll Test
The purpose of the roll test is to determine if the unit's
gears are rotating freely and properly. You should be able
to rotate the wheel or hub of the gearbox by hand. If you
feel more drag in the gears only at certain points, then the
gears are not rolling freely and should be examined for
improper installation or defects. Some gear packages roll
with more difficulty than others. Do not be concerned if
the gears in your unit seem to roll hard as long as they roll
with consistency.
The Leak Test
The purpose of a leak test is to make sure the unit is air
tight. You can tell if your unit has a leak if the pressure
gauge reading on your leak checking fitting starts to fall
after the unit has been pressurized and allowed to equal-
ize. Leaks will most likely occur at the pipe plugs, the
main seal or wherever o-rings are located. The exact loca-
tion of a leak can usually be detected by brushing a soap
and water solution around the main seal and where the o-
rings or gaskets meet on the exterior of the unit, then
checking for air bubbles. If a leak is detected in a seal, o-
ring or gasket, the part must be replaced, and the unit
rechecked. Leak test at 10 psi for 20 minutes.
NOTE: Due to the small air volume inside this Torque-Hub, it will
pressurize to 10 psi very quickly. If the pressure becomes
excessive in the unit the seals will be destroyed.
Oil Type & Capacity
This torque hub unit is shipped with ISO 68 viscosity oil
(hydraulic fluid). It is designed to utilize the same oil
throughout its service life. However, should it need to be
serviced the oil will need to be drained and replaced.
When serviced, fill the unit with ISO grade 68 oil or oil of a
similar viscosity (80W gear oil or 20W engine oil).
The gearbox will need to be filled with 10 oz. of oil.
Oil Filling Instructions
10 oz. of gearbox oil will fill the gearbox cavity approxi-
mately half full. To check the oil level, rotate the wheel so
that the cover plugs are at 12 o-clock and 3 o-clock. Allow
the oil to settle. Slowly loosen the 3 o-clock plug. If oil
begins to come out then the oil level is sufficient. If no oil
is noticed at the 3 o-clock plug location, then remove both
plugs. Slowly add oil at the 12 o-clock plug location until
oil begins to seep out of the 3-clock plug location. Re-
install and tighten plugs to 6-8 ft-lbs.
Drive Motor Power Harness Routing
Figure 4-3. Drive Motor Power Harness Routing