Hyundai R 160 LC-3, Service Manual

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When the right control lever is manually placed in the bucket roll out position. Then the oil flows from
pilot pump through the pilot valve to bucket section of the main control valve. Here the spool position
is moved to bucket roll out position.
The oil flows from rear pump through bucket section of main control valve to the rod end of the
bucket cylinder, and to roll out bucket.
The return oil flows from the bottom end of the cylinder through the bucket section returned to the
tank.
The cavitation which will happen to the rod 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.
6. BUCKET ROLL OUT 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