Lull 944E-42 Service Manual - Manual (Page 394)

Hydraulic System
8.142 Model 644E-42/944E-42 Rev. 6/04
8.8.44 Auxiliary Hydraulic Pressure Release Circuit & Troubleshooting (Dual Joystick)
(644E-42, SN 20118 & Before, SN 0160002519 thru 0160003108)
(944E-42, SN 20123 & Before, SN 0160002514 thru 0160003106)
(Refer to Section 8.8.63, “Auxiliary Hydraulic Pressure Release Valve (644E-42, SN 20118 & Before,
SN 0160002519 thru 0160003108) (944E-42, SN 20123 & Before, SN 0160002514 thru 0160003106),” 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
ACCUMULATOR
CHARGE/SECONDARY
FUNCTION VALVE
LS
DRAIN P1
LSG ACR
SW P
ACF EF CF PIL PB
PBG
PPG
SW
MAIN CONTROL
VALVE
INLET
OUTLET
HYDRAULIC OIL
COOLER
FRONT
JOYSTICK
PILOT SELECT
VALVE
4
T
P 3
AUXILIARY
COUPLERS
1 2
CHECK VALVE
85 PSI (5,9 bar)
RETURN
FILTER
25 PSI
(1,7 BAR)
BYPASS
CHECK
VALVE
P1
P2
B1
B3
A1
A3
AUXILIARY
HYDRAULIC
PRESSURE
RELEASE
VALVE
AUXILIARY
HYDRAULIC
PRESSURE
RELEASE
SWITCH
SHUTTLE
VALVE
MU5572 Relief Valve
Male
Coupler
Main
Relief
Valve
Implement
Pump
Pressure
Tap
Pressure
Reducing
Cartridge
“PPG”
Pressure
Tap
Female
Coupler