The emergency pressure then has a free flow to the unit outlet port, but is prevented from entering the normal system by the shuttle. Maintenance of Shuttle Valves Shuttle valve maintenance is generally limited to repairing leakage. External leakage may generally be repaired by tightening the end caps. If this does not stop excessive leakage, the end cap O-rings should be replaced. Internal leakage can usually be repaired by removing and flushing the unit with clean hydraulic fluid.
Excessive heating is a good indication of internal leakage through a shuttle valve.
Excessive cycling of the emergency system pump is also an indication of a leaky shuttle valve. After an emergency system has been operated, all emergency system pressure should be bled off as soon as possible, and the normal system restored to operation. If control in one direction only is desired, a one-way restrictor is used. If restricted fluid flow both to and from an actuating cylinder is necessary, a two-way restrictor is installed. Integrated Publishing's Official Web Page Click here for a current index of everything on this web site.