Lull 944E-42 Service Manual - Manual (Page 334)

Hydraulic System
8.82 Model 644E-42/944E-42 Rev. 6/04
8.8.14 Boom Lift Circuit & Troubleshooting (Dual Joystick)
(Refer to Section 8.8.53, “Boom Lift/Lower Circuit Description (Dual Joystick),” for a more detailed
explanation of this circuit.)
Suction
Return
Load Sense
Pressure
Pilot Pressure
PUMP
HYDRAULIC
RESERVOIR
ATTACH
TILT
FRAME
EXT/RET LFT/LWR
AU
X
TRANS
E
R
ACCUMULATOR
CHARGE/SECONDARY
FUNCTION VALVE
LS
DRAIN P1
LSG ACR
SW P
ACF EF CF PIL PB
PBG
PPG
SW
INLET
OUTLET
HYDRAULIC OIL
COOLER
REAR JOYSTICK
LIFT/LOWER
CYLINDER
1 2
3
T
P
4
CHECK VALVE
85 PSI (5,9 bar)
RETURN
FILTER
25 PSI
(1,7 BAR)
BYPASS
CHECK
VALVE
MAIN
CONTROL
VALVE
MU0591
Pressure
Reducing
Cartridge
Main
Relief
Valve
“PPG”
Pressure
Tap
Implement
Pump Pressure
Tap
Pilot Supply
Line
Unloader
Cartridge