Hyundai R 160 LC-3, Service Manual

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When the right control lever is manually placed in the bucket roll in position. Then the oil flows from
pilot through the pilot valve to bucket section of the main control valve. Here the spool position is
moved to bucket roll in position.
The center bypass valve is change over by the pilot pressure(XAk2) and then the oil from front pump
is joint to the flow of rear pump via confluence passage.
The oil flows from both pump through rod end of the cylinder through the bucket section returned to
the tank.
The cavitation which will happen to the bottom of the bucket cylinder is prevented by a make up
valve, on other hand. The excessive pressure is also prevented by an overload relief valve in the
main control valve.
5. BUCKET ROLL IN OPERATION
TRAVEL MOTOR
ARM CYLINDER BOOM CYLINDER
SWING MOTOR
HYD
TANK
FRONT
PUMP REAR
PUMP PILOT
PUMP
P1 P2 R
BUCKET
BUCKRT CYLINDER
XBk
XAk2
Ck2
XAk
XAk2
CENTER
BYPASS VALVE
MAKE UP VALVE
RELIEF VALVE
Ck1