. MAINTENANCE MAINTENANCE PROCEDURE MAINTENANCE MAINTENANCE PROCEDURE 4 - 75 5. Open mud cover (1), then r emove the cap of oil filler (F) to . release the internal pressure 6. Place a container under the d rain plug which is located on the machine underside. Then r handle, and drain oil. At that time, check the O-r replace it with a new one, if draining oil, tighten drain plu Tightening torque of the drai Take care not to get oil on plug (P). machine underside. Then r handle, and drain oil. At that time, check the O-r replace it with a new one, if emove drain plug (P), using a ing fitted to drain plug (P) and any damage is found on it. After g (P) again. n plug:
68.6 ± 9.81 N·m (7 ± 1 kgf·m, 51 ± 7 lbft) draining oil, tighten drain plu Tightening torque of the drai Take care not to get oil on yourself when you remove drain cover (2). 7. Loosen 4 bolts, then remove When doing this, the cover m ay fly out under the force of spring (3), so push the cover down when removing the bolts. 8. Pull up the top of rod (4), an (4). Remove the dirt stuck to st diesel oil or flushing oil. d remove spring (3) and strainer rainer (5), then wash it in clean place it with a new one. it into tank projecting part (6). cover (2), and if it is damaged, f new and clean engine oil (for 9. If strainer (5) is damaged, re 10. Refit strainer (5) by inserting 11.
Install cover (2) with bolts. Check the O-ring installed to replace the O-ring. Add the specified amount o 12. hydraulic system) through oi l filler port (F). Check that the oil he sight gauge. level is between H and L on t For details of oil level check, see "Check Oil Level in Hydraulic Tank, Add Oil (PAGE 3-63)". 13. Swing the boom to the central position as shown in the diagram on the right, extend the boom , arm, and bucket cylinders fully, then remove the oil filler ca pressurize the tank. p, and install the cap again to NOTICE Be s ure to pressurize the hydraulic ta nk. If it is not pressurized, the pump will suck in air, and this will adversel y affect the equipment. 14.
After replacing hydraulic oil and cleaning or replacing filter ir from the circuit. element and strainer, bleed a For details of the method of b leeding the air, see "BLEEDING AIR FROM HYDRAULIC SY STEM (PAGE 4-47)".