Replace Pilot Oil Filter - Hitachi ZW180 Operator's Manual

4
Replace Pilot Oil Filter --- every 2000 hours
WARNING: Hydraulic oil becomes hot and pressur-
ized during operation. Severe burns may result if skin
comes in contact with escaping hydraulic oil imme-
diately after operation. Wait for the oil to cool before
starting any maintenance work.
1. Park the machine on solid level surface. Lower the bucket
to the ground. Stop the engine.
2. Turn the parking brake switch (1) ON. Press the neutral
lever lock (2) to the LOCK position.
3. Lock the front and rear frames with the articulation lock
bar.
4. Before replacing the filter element, be sure to relieve the
air pressure from the hydraulic oil tank by pressing air
bleed valve (3).
5. Remove the inspection cover for left side rear frame.
6. Rotate the hexagonal section on the bottom of case (4)
counterclockwise using a spanner to remove case (4)
from head cover (5).
7. While turning element (7), remove the element down-
ward.
8. Replace O-ring (6) with a new one.
9. Sufficiently seat O-ring (6) in the O-ring groove on head
cover (5).
10. Coat the seal surface of new element (7) with hydraulic
oil. While turning element (7), completely install element
(7) into head cover (5) using care not to damage the ele-
ment.
11. Take care never to allow water and/or dust to enter the
filter case.
12. Install case (4) into head cover (5) while rotating case (4)
clockwise.
Tightening torque: 39 N•m (4 kgf•m)
19.6 to 29.4 N•m (2 to 3 kgf•m)
13. After replacing the filter, bleed air from the hydraulic
pump and check the oil level in the hydraulic oil tank.
[Refer to the descriptions for "Bleed air from the hydraulic
system" in 2 .] If the machine is operated without bleed-
ing the air mixed in the hydraulic circuit, damage to the
hydraulic pump may result.
NOTE: Replace the element at the regular intervals to main-
tain the clean hydraulic oil and extend the service life-
time of the hydraulic components.
MAINTENANCE
2
7-46
1
M4GB-01-0004
3
M4GB-07-044
4
M4GB-07-049
5
6
7
4
M4GB-07-050