6 main valve block pressure setting procedures, Telescope, Main relief – JLG 450A_AJ Series II Service Manual User Manual
Page 307: Steer, Lift down, Swing, 7 platform valve block pressure setting procedures, Platform level extend, Platform level retract, Articulating jib (aj only)
SECTION 5 - HYDRAULICS
3121290
– JLG Lift –
5-67
5.6
MAIN VALVE BLOCK PRESSURE SETTING
PROCEDURES
NOTE:
Refer to Figure 5-115., Main Control Valve.
Cold temperatures have a significant impact on pressure read-
ings. JLG Industries Inc. recommends operating machine until
hydraulic system has warmed to normal operating tempera-
tures.
Check pressures with a calibrated gauge. Pressure readings
must be ± 5% of specified pressures.
Turn relief valves clockwise to increase or counter-clockwise to
decrease pressure.
Telescope
1.
Install high pressure gauge in port M1 (11).
2.
Activate telescope in.
3.
Set Telescope relief valve (12) to 3300 psi (230 bar).
Main Relief
1.
Install high pressure gauge in port M2 (1).
2.
Raise boom up to end of stroke, or remove hose from
port #10 and plug and cap. Activate lift up.
3.
Set Main relief valve (13) to 3200 psi (220 Bar).
Steer
1.
Install high pressure gauge in port M3 (19).
2.
Set Steer relief valve (14) to 2500 psi (170 bar).
Lift Down
1.
Install high pressure gauge in port M2 (1).
2.
Activate lift down.
3.
Set Lift Down relief valve (15) to 1200 psi (80 bar).
Swing
NOTE:
Left and right is a single adjustment.
1.
Install high pressure gauge in port M4 (18).
2.
Remove one swing hose, and plug and cap, or swing
turntable around until it hits stop. Activate swing.
3.
Set Swing relief valve (2) to 1700 psi (120 bar).
5.7
PLATFORM VALVE BLOCK PRESSURE SETTING
PROCEDURES
NOTE:
Refer to Figure 5-116., Platform Control Valves.
Cold temperatures have a significant impact on pressure read-
ings. JLG Industries Inc. recommends operating machine until
hydraulic system has warmed to normal operating tempera-
tures.
Check pressures with a calibrated gauge. Pressure readings
must be ± 5% of specified pressures.
Turn relief valves clockwise to increase or counter-clockwise to
decrease pressure.
Platform Level Extend
1.
Install high pressure gauge in port M2 (9)
.
2.
Activate level up to end of stroke. Set relief valve (10) to
2800 psi (190 bar).
Platform Level Retract
1.
Install high pressure gauge in port M1 (7).
2.
Activate level down to end of stroke. Set relief valve (8)
to 1800 psi (125 bar).
Articulating Jib (AJ Only)
1.
Install high pressure gauge in port M3 (5).
2.
Activate Jib up or down. Set relief valve (6) to 1500 psi
(105 bar).