320B Excavator Hydraulic System / Relief Valve (Swing) - Test and Adjust
Relief Valve (Swing) - Test and Adjust
1. Position the machine on level ground.
2. Stop the engine.
3. Release the pressure in the hydraulic system. Refer to Testing And Adjusting, "Hydraulic System Pressure - Release".
Pump compartment (1) Pressure tap (power shift pressure) p ressure) (2) Pressure tap (upper pump delivery pressure)(3) Pressure tap (lower pump delivery pressure)
4. Connect a 60000 kPa (8700 psi) pressure gauge to pressure tap (3) .
Swing motor (26) Connector(27) Solenoid valve for swing parking brake
5. Disconnect connector (26) from the solenoid valve for swing p arking brake (27) .
6. Start the engine.
7. Place the machine controls at the following settings: Power Mode, engine speed dial "10" and AEC switch OFF.Reference: Make reference to Testing And Adjusting, "Operational Checks" for engine rpm settings.
8. Increase the hydraulic oil temperature to 55° ± 5 °C (131° ± 9°F).
9. Move the swing control lever slowly and ensure th at the swing parking brake is operating properly.
10. Slowly move the swing control lever for a full R IGHT swing operation and check the pressure setting for relief relief valve (24) at pressure tap (3) .
11. Return the swing control lever to the NEUTRAL p osition.
12. The pressure setting for the swing relief valve is 24000 ± 980 kPa (3500 ± 140 psi). If the pressure setting of the swing relief relief valve is not within the specification, adjust the swing relief valve.
13. In order to adjust the swing relief valve, loosen locknu t (23). Turn adjustment plug (22) until the pressure gauge reading at pressure tap (3) is 24000 ± 980 kPa kP a (3500 ± 140 psi).Note: Turning adjustment plug (22) clockwise increases the pressure. Turning adjustment plug (22) counterclockwise decreases the pressure.
14. Tighten locknut (23) to a torque of o f 160 ± 30 N·m (120 ± 22 lb ft).
15. Slowly move the swing control lever for a full LEFT swing operation and check the pressure for relief valve (25) at pressure pressure tap (3) .
16. Return the swing control lever to the NEUTRAL position.
17. The pressure setting for the swing relief valve is 24000 ± 980 kPa (3500 ± 140 psi). If the pressure setting of the swing relief relief valve is not within the specification, adjust the swing relief valve.
18. Adjust relief valve (25) for left swing in the same manner as relief valve (24) for right swing.Note: Always make final pressure adjustments on pressure rise.
