Replace Hydraulic Oil Return Filter - Hitachi ZW 370-6 Operator's Manual

Replace Hydraulic Oil Return Filter

--- every 1000 hours
d
WARNING: Hydraulic oil becomes hot during
operation. Severe burns may result if skin comes in
contact with hot hydraulic oil. Wait for the oil to cool
before starting any maintenance work.
Especially when removing the filter, be careful that
the remaining oil in the filter does not spill.
Replacement Procedures
1. Park the machine following the same procedures as
described on page 7-6 for preparation of inspection/
maintenance work.
2. Install articulation stopper (lock bar) to the front
and rear of the chassis by following the procedures
described on page 7-8.
3. Clean the vicinity around cover plate (1).
4. Get a container and workshop towels to hold the spilled
oil and the element.
Relieve the air pressure from the hydraulic oil tank by
pressing air bleed valve (6).
5. Loosen bolts (2) (6 used) to remove cover (1) and O-ring
(3).
When removing cover (1), slowly remove the cover
while pressing the cover downward so that spring
(4) does not fly off. Slowly permit cover to rise, then
carefully remove.
6. Remove spring (4), and element (5).
7. Replace element (5) and O-ring (3) with new ones.
Install new element and new O-ring in the hydraulic oil
tank.
Before installing element (5), make sure that rubber (7)
is present.
8. Install cover (1) with bolts (2) (6 used).
m : 50 N·m (5.0 kgf·m, 37 lbf·ft)
9. After replacing the return filter element, 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 item 2 .]
If the machine is operated without bleeding the air
mixed in the hydraulic circuit, damage to the hydraulic
pump may result.
f
NOTE: Replace the element at the regular intervals to
maintain clean hydraulic oil and extend the service life of the
hydraulic components.
MAINTENANCE
7-47
6
1
2 1
95Z7B-7-42-2
3
4
5
7
M4GB-07-052