JLG 510AJ Service Manual - Manual (Page 101)

SECTION 3 - CHASSIS AND TURNTABLE
3121181 – JLG Lift – 3-59
Lockout Cylinder Bleeding (Ram Cylinders)
NOTE: The following procedure is to be used on machines built S/
N 1300003222 to present.
1. Position the turntable to it’s normal stowed position. In
this position, the axle is free to oscillate. Drive charge
pressure will pass through the lockout valve built into
the swivel and down to the pilot section of the holding
valves on the cylinders. This will automatically purge air
from the pilot section of the circuit.
2. Disconnect the brake wire connector on the brake valve
located under the drive pump.
3. Locate the bleeder on the lockout cylinders. Use a small
hose (such as a gas hose, etc.) to direct the oil to a
bucket. Do one cylinder at a time. Using a small wrench,
open the bleeder 1/4 turn. Have the operator in the plat-
form just crack the drive controller in reverse. This will
activate the brake valve sending charge pressure to the
lockout cylinder. Make sure the bleeder is open enough
to vent any air for about 10 seconds. Close the bleeder
while there is fluid pressure at the bleeder.
4. Repeat the procedure for the other lockout cylinder.
5. Reconnect the brake wire connector on the brake valve.
Oscillating Axle Lockout Test
LOCKOUT SYSTEM TEST MUST BE PERFORMED QUAR-
TERLY, ANY TIME A SYSTEM COMPONENT IS REPLACED, OR
WHEN IMPROPER SYSTEM OPERATION IS SUSPECTED.
NOTE: Ensure boom is fully retracted, lowered, and centered
between drive wheels prior to beginning lockout cylinder
test.
1. Place a 6 inch (15 cm) high block with ascension ramp in
front of left front wheel.
2. From platform control station, activate machine hydrau-
lic 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 con-
trol lever to REVERSE and drive machine off of block and
ramp.
7. Have an assistant check to see that left front wheel
remains locked in position off of ground.
8. Carefully activate SWING control lever and return boom
to stowed position (centered between drive wheels).
When boom reaches center, stowed position, lockout
cylinders should release and allow wheel to rest on
ground, it may be necessary activate DRIVE to release
cylinders.
9. Place the 6 inch (15 cm) high block with ascension ramp
in front of right front wheel.
10. Place DRIVE control lever to FORWARD and carefully
drive machine up ascension ramp until right front wheel
is on top of block.
11. Carefully activate SWING control lever and position
boom over left side of machine.
12. With boom over left side of machine, place DRIVE con-
trol lever to REVERSE and drive machine off of block and
ramp.
13. Have an assistant check to see that right front wheel
remains locked in position off of ground.
14. Carefully activate SWING control lever and return boom
to stowed position (centered between drive wheels).
When boom reaches center, stowed position, lockout
cylinders should release and allow wheel to rest on
ground, it may be necessary activate DRIVE to release
cylinders.
15. If lockout cylinders do not function properly, have quali-
fied personnel correct the malfunction prior to any fur-
ther operation.