JLG 450AJ ANSI Service Manual User Manual
Page 96
SECTION 2 - PROCEDURES
2-78
– JLG Lift –
3120749
Bang-Bang Sequence Valve
1.
Install the pressure gauge at port G2 on the Main
Valve.
2.
Energize the main dump valve by applying 12 volts
to pin 14 at the ground control box. The gauge
should read between 230 and 325 psi (16 and 22.5
bar). This valve is non-adjustable.
P1 Main Relief Valve
1.
Install the pressure gauge at port G1 on the Main
Valve.
2.
Remove the hose from port LC. Plug the hose and
cap the fitting on the valve block.
3.
Activate Lift Up and hold.
4.
The pressure gauge should read 3000 +200, -50 psi
(207 +14, -3.5 bar).
P2 Main Relief Valve
1.
Install the pressure gauge at port G2 on the Main
Valve.
2.
Activate Tower Lift Down and hold.
3.
The pressure gauge should read 3200 +200, -50 psi
(220 +14, -3.5 bar).
Swing
1.
Remove the hoses at ports S1 and S2 on the Main
Valve and plug both hoses.
2.
Install pressure gauges into both port S1 or S2.
3.
Activate swing fully left or right. Adjust the valve to
1750 +200, -0 psi (121 +14, -0 bar).
Upper Lift Down
1.
Remove the hoses at port B2 on the Main Valve and
plug the hose.
2.
Install pressure gauges into port B2.
3.
Activate lift down and hold.
4.
The pressure gauge should read 2500 +200, -0 psi
(172 +14, -0 bar).
Platform Level Retract
1.
Remove the hose from port B1 on the Main Valve
and cap it.
2.
Install a pressure gauge into port B1.
3.
Activate the level down function and hold.
4.
The pressure gauge should read 2500 +200, -0 psi
(172 +14, -0 bar).
Telescope Relief
1.
Remove the hoses at ports TC and TR and plug.
2.
Install pressure gauges into both ports TC and TR.
3.
Activate Telescope In and Out.
4.
The pressure gauge should read 2000 +200, -0 psi
(138 +14, -0 bar).
Jib Relief
1.
Remove the hoses at ports J1 and J2 and plug.
2.
Install pressure gauges into both ports J1 and J2.
3.
Activate the Jib up and down.
4.
The pressure gauge should read 1500 ±100 psi
(103 ± 7 bar).
Steer Relief
1.
Remove the hoses at ports ST1 and ST2 and plug.
2.
Install pressure gauges into both ports ST1 and ST2.
3.
Activate the steer left and right.
4.
The pressure gauge should read 2000 ±100 psi
(138 ± 7 bar).