Experts at Parker Hannifin recommend a 13-step procedure when a hydraulic system has a failure. Following it can help prevent repeat failures.
- Determine cause of failure.
- Eliminate cause of failure.
- Retract all cylinders and drain tank.
- Flush tank using diesel fuel under pressure, wipe with clean cloths.
- Install new filter elements (10 microns or better).
- Install new component.
- Fill tank with new hydraulic oil.
- Disconnect all lines to cylinders and/or motors, ensuring that all implements are securely blocked and all accumulators bled before disconnecting.
- Activate each circuit by moving the control valve handle so lines are flushed with new oil. Check oil level and add as necessary.
- Connect lines to blind end of cylinders and fluid motors. Leave rod end disconnected. With engine at 1/4 throttle, activate circuits slowly until cylinder bottoms out. New oil will be put in the blind end of the cylinder and the old oil flushed out the rod end. Do this for all cylinders.
- Connect lines to rod end of cylinders. Check oil level and add as necessary.
- Operate all cylinders and motors alternately for 30 minutes at normal operating speed.
- Change filter element, check oil level and add as needed.