Service Manual

SECTION 3 - CHASSIS & TURNTABLE
3-34 – JLG Lift – 3121202
3.5 OSCILLATING AXLE BLEEDING
PROCEDURE AND LOCKOUT TEST
Lockout Cylinder Bleeding
ENSURE PLATFORM IS FULLY LOWERED AND BOOM IS CEN-
TERED OVER REAR AXLE PRIOR TO BEGINNING BLEEDING PRO-
CEDURE.
ENSURE MACHINE IS ON A LEVEL SURFACE AND REAR WHEELS
ARE BLOCKED, BRAKE WIRE IS DISCONNECTED.
1. Making sure machine is on a level surface and rear
wheels are blocked, brake wire is disconnected.
2. Center boom over rear axle to make sure that the
oscillation valve in the rotary coupling is activated.
3. Using a Phillips screwdriver, remove screw from
connection on the brake valve and disconnect the
solenoid from the valve
4. Place suitable containers under each lockout cylin-
der to catch any residual hydraulic fluid.
5. Open both bleeder screws (one on each lockout cyl-
inder).
6. Start the engine, position drive control lever to for-
ward or reverse.
7. Close bleeder screws when there is no more air in
the hydraulic oil coming out of the bleeder valve.
8. Perform oscillating axle lockout test.
9. If necessary, repeat steps 1 thru 8.
Oscillating Axle Lockout Test
LOCKOUT SYSTEM TEST MUST BE PERFORMED QUARTERLY,
ANY TIME A SYSTEM COMPONENT IS REPLACED, OR WHEN
IMPROPER SYSTEM OPERATION IS SUSPECTED.
NOTE: Ensure boom is fully retracted, lowered, and cen-
tered between drive wheels prior to beginning lock-
out cylinder test.
1. Place a 6 inch (15.2 cm) high block with ascension
ramp in front of left front wheel.
2. From platform control station, activate machine
hydraulic system.
3. Place FUNCTION SPEED CONTROL and DRIVE
SPEED/TORQUE SELECT control switches to their
respective LOW positions.
4. Place DRIVE control lever to FORWARD position
and carefully drive machine up ascension ramp until
left front wheel is on top of block.
5. Carefully activate SWING control lever and position
boom over right side of machine.
6. With boom over right side of machine, place DRIVE
control lever to REVERSE and drive machine off of
block and ramp.