Hitachi ZW180 Technical Manual page 122

Neutral Circuit
•
At neutral of the control lever, pressure oil from
the main pump returns to the hydraulic oil tank
through the neutral circuit of the control valve.
•
Only when the steering valve spool moves due to
the priority valve, pressure oil is supplied to the
steering valve. Therefore, the steering valve is not
provided with a neutral circuit. (Refer to Priority
Valve Circuit in this section.)
Single Operation Circuit
•
Pressure oil from the main pump flows to the
control valve, and flows to the lift arm and bucket
spools.
•
When the steering valve spool moves, the priority
valve spool moves leftward, and pressure oil from
the main pump flows to the steering valve. (Refer
to Priority Valve Circuit in this section.)
SYSTEM / Hydraulic System
T2-3-6