Air Bleeding Procedures - Hitachi ZAXIS 135US-5B Operator's Manual

Air Bleeding Procedures

IMPORTANT: If the hydraulic pump is not filled with oil, it
will be damaged when the engine is started.
The machine is equipped with two main pumps. Bleed air
from these pumps after changing hydraulic oil.
1. Remove air bleed plug (5) on each pump.
2. Fill the pump with oil through air bleed plug (5) port on
each pump until oil flows out of air bleed plug (5) hole.
3. Temporarily tighten air bleed plug (5) on each pump,
start the engine and run at slow idle. Loosen one of air
bleed plugs (5) slightly until oil flows from plug port to
release trapped air completely. Tighten air bleed plug (5).
Repeat this step for the rest of plugs (5).
Tightening torque: 95 N·m (9.5 kgf·m)
4. Purge air from the hydraulic system by running the
engine at slow idle and operating the control levers
slowly and smoothly for 15 minutes.
5. Position the machine as illustrated in the oil level
checking procedure.
6. Lower the bucket to the ground.
7. Turn the auto-idle switch off.
8. Stop the engine. Remove the key from the key switch.
9. Pull the pilot control shut-off lever to the LOCK position.
10. Check the hydraulic oil tank gauge. Remove cover to add
oil if necessary.
MAINTENANCE
7-39
5
ZX135US-5B
5
ZX225US-5B, 225USLC-5B
MDAA-07-072
MDAA-07-001