Service Manual User guide

Hydraulic System
8.60
Model 644E-42/944E-42 Rev. 6/04
8.8.3 Pump & Cooling Circuit & Troubleshooting (Single Joystick)
(Refer to Section 8.8.47, “Pump and Cooling Circuit Description (Single Joystick),” for a more detailed
explanation of this circuit.)
RETURN
FILTER
25 PSI
(1,7 BAR)
BYPASS
CHECK
VALVE
SINGLE
JOYSTICK
PILOT
SELECT
VALVE
P1
TB
TA
AUX2
AUX1
EB
EA
HB
HA
CTB
CTA
T
P
P2
P3 P4
SINGLE
JOYSTICK
HYDRAULIC OIL
COOLER
CHECK VALVE
85 PSI (5,9 bar)
HYDRAULIC
RESERVOIR
Suction
Return
Load Sense
Pressure
Pilot Pressure
1
3
T
P
4
2
MAIN CONTROL
VALVE
INLET
OUTLET
BRIDGE DRAIN
ATTACH
TILT
FRAME
EXT/RET
LFT/LWR
AUX
TRANS
ACCUMULATOR
CHARGE/SECONDARY
FUNCTION VALVE
LS
DRAIN P1
LSG
ACR
SW P
ACFEFCF PIL
PB
PBG
PPG
SW
FRAME
SWAY
JOYSTICK
P
T
2
1
PUMP
MU5430