Hitachi ZW180 Technical Manual page 218

Pilot Operation Circuit
Pressure oil indicated with numbers from the pilot
valve acts on the spool of the control valve, and
moves the spool.
•
Pressure oil is sent to the bucket spool for
dumping and crowding operations.
•
Pressure oil is sent to the lift arm spool for raising
and lowering operations.
The spool for lowering is two-staged. The first
stage is when lowering the lift arm and the second
stage is when floating the lift arm.
COMPONENT OPERATION / Control Valve
T3-2-10