Torque Hub Servicing; Roll Test; Leak Test; Oil Check/Fill Procedure - JLG 1932RS/6RS Service And Maintenance Manual

SECTION 3 - CHASSIS & SCISSOR ARMS

3.14 TORQUE HUB SERVICING

THE PROCEDURES WITHIN THIS SECTION APPLY TO ALL MACHINES AND
TORQUE HUBS. PROCEDURES THAT APPLY TO SPECIFIC MACHINES AND
TORQUE HUBS WILL BE SO NOTED BY PROPER SERIAL NUMBERS.
NOTE: These instructions will cover how to completely assemble
and disassemble the Torque-Hub unit. However, if the unit
is under warranty you should contact JLG Industries, Inc.
for a replacement unit. The warranty will no longer be valid
if the unit is disassembled by non-JLG personnel.
TORQUE HUB UNITS SHOULD ALWAYS BE ROLL AND LEAK TESTED BEFORE DIS-
ASSEMBLY AND AFTER ASSEMBLY TO MAKE SURE THAT THE UNIT'S GEARS
AND SEALANTS ARE WORKING PROPERLY.
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.
IF THE MACHINE IS ON ANY INCLINE, THE WHEELS MUST BE ADEQUATELY
BLOCKED PRIOR TO MANUALLY DISENGAGING THE BRAKES. FAILURE TO DO
SO MAY RESULT IN INJURY OR EVEN DEATH.
NOTE: The brake must be released before performing the roll test.
This can be accomplished by connecting the brake release
cable and depressing button. The brake can also be
released by following the manual disengage procedures
outlined in this section.
RE-ENGAGE BRAKES BEFORE RETURNING TO NORMAL OPERATION.

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 roll-
ing 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.
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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 read-
ing on your leak checking fitting starts to fall after the unit has
been pressurized and allowed to equalize. Leaks will most
likely occur at the pipe plugs, the main seal or wherever o-
rings are located. The exact location 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 exte-
rior 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 Check/Fill Procedure

The torque hub unit is shipped with ISO 68 viscosity oil
(hydraulic fluid). It is designed to utilize the same oil through-
out its service life. However, should it need to be checked/ser-
viced use the following procedure.
In the event of servicing, fill the unit with ISO grade 68 hydrau-
lic oil.
NOTE: The gearbox capacity is 10 oz of oil.
1. To check the oil level, rotate the wheel so that the plugs
in the cover are at 12 o-clock and 3 o-clock.
2. Allow the oil to settle than slowly remove the plug at 3
o-clock.
3. If oil begins to come out the oil level is sufficient.
4. If no oil is noticed at the 3 o-clock plug remove both
plugs.
5. Slowly add oil at the 12 o-clock plug location until oil
begins to seep out at the 3 o-clock plug location.
6. Apply pipe dope or teflon tape to the cover plugs and
reinstall into the cover.
7. TIghten to 6 ft lbs - 8 ft lbs (8.4 Nm to 11.2 Nm).
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