Komatsu D155A-6 Operation & Maintenance Manual page 314

MAINTENANCE MAINTENANCE
4. After checking that the hydraulic oil temperature has gone
down, turn filter case (3) to the left, remove it, then take out
element (4).
5. Clean the removed parts, then install new element (4).
Element (4) must be installed facing in the correct direction.
Set direction Y with the holes in it facing up, and insert the
hole in element (4) on the protruding portion inside filter
head (6).
6. Install new O-ring (5) to filter case (3), then tighten filter case (3)
to a tightening torque of 25 - 35 Nm (2.6 - 3.6 kgm, 18.8 - 26.0
lbft).
7. Install cover (2) with bolt (1) as before.
SERVICE PROCEDURE SERVICE PROCEDURE
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