Replace Hydraulic Oil Tank Filter - Hitachi EX27U Operator's Manual

Replace Hydraulic Oil Tank Filter

--- every 500 hours
1. Park the machine on a level surface.
2. Lower the bucket and blade to the ground.
3. Run the engine at slow idle speed without load for
three minutes.
4. Stop the engine. Remove the key from the key
switch.
5. Pull the pilot control shut-off lever to the LOCK posi-
tion.
CAUTION: The hydraulic oil tank is pressurized.
Slowly loosen the cap to release the pressure.
6. Slowly loosen the cap to release the pressure, then
remove the cap.
EX27u, EX35u
NOTE: There is spring tension under the cover. Hold
down the cover when removing last two bolts.
7. Hold down filter cover (2) against light spring load
when removing the last two bolts (1). Remove filter
cover (2).
8. Remove spring (4), valve (5) and element (6).
NOTE: Remove the element and inspect for metal par-
ticles and debris in the bottom of the filter can.
Excessive amounts of brass and steel particles
can indicate a failed hydraulic pump, motor,
valve or an impending failure. A rubber type of
material can indicate cylinder packing failure.
9. Discard element (6) and O-ring (3).
10. Install a new element (6), valve (5) and spring (4).
11. Install filter cover (2) with a new O-ring (3).
12. Install and tighten bolts (1) to 49 N⋅m (5 kgf⋅m, 36
lbt⋅ft).
IMPORTANT: If the hydraulic pump is not filled with oil,
it will be damaged when the engine is
started.
Purge air from the hydraulic pump.
(Refer to Bleed Air from the hydraulic system.)
Check the hydraulic oil tank gauge add oil if necessary.
MAINTENANCE
7-29
1 2
M586-05-030
3
4
5
6
M589-07-019