Komatsu PC118MR-8 Operation And Maintenance Manual page 365

MAINTENANCE
5. Loosen the screws and remove the cover (4).
REMARK
During this operation, be careful to the thrusting force of the
spring (5).
6. Remove the rod (6), the spring (5) and the filter (7).
7. Remove any dirt from the filter (5), then wash it with clean
diesel oil or wash oil.
NOTICE
Carefully check the filtering element grid and if it is not in
perfect conditions, change it.
8. Insert the filter (7) in the protruding part of the tank (8) and
reassemble the whole by proceeding in the reverse order.
NOTICE
Make sure that the gasket of the cover (4) is not damaged
and is correctly housed in its seat in the tank.
9. Put back the drain plug (P) and add oil through the filler
neck (3) until reaching a level included between the H and
L marks on the gauge (G).
Use only synthetic biodegradable hydraulic oil type HEES
(see "APPROVED SYNTHETIC BIODEGRADABLE
LUBRICANTS TYPE HEES (4-14)").
10. Move the boom to the centre and extend the boom, arm
and bucket cylinders completely, as shown in the diagram
on the right.
11. Remove the plug (3).
12. Put back the cap and pressurize the tank, lowering the
equipment to the ground.
13. Close the cap lock (3) and the side hood (1).
NOTICE
Make sure that the hydraulic tank is pressurised. If the
tank isn't under pressure, the pump will suck in air and
this will damage the equipment.
14. Run the engine at idle speed for 2-3 minutes with all the control levers in the neutral position.
15. Actuate each piston repeatedly to bleed the system; check the oil level and top it up if necessary. 
For details on the bleeding procedure, see "BLEEDING THE HYDRAULIC SYSTEM (4-41)".
WEAM014802
MAINTENANCE PROCEDURES
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