TROUBLESHOOTING, TESTING AND ADJUSTMENT INSPECTION The center joint should be checked for evidence of external oil leakage every 2,000 hour of operation. Leaking or defective O-rings are an indication that dirt and other contaminants could be getting inside the assembly, which will promote accelerated, abnormal wear and may cause early failure of the assembly. If internal seals or other sliding surface components are worn and there is internal fluid leakage, complete overhaul and repair or replacement of the center joint may be required. TESTING To check pressure through the center joint, make up a test kit from the following equipment list:
Pressure Gauge 700 bar (10,000 psi) pressure gauge Adapters, connectors, piping and flange block-off plates conforming to those used in high pressure piping connections of the excavator. Swivel Joint Body (Outer) Swivel Joint Stem (Inner) A high pressure relief valve with a setting pressure 1.5 times maximum system pressure. Stop Valve A stop valve A manually operated, in-line change- over valve. Manually-Operated Changeover Valve Install the change over valve upstream from one of the stem high-pressure ports. Connect the pressure gauge downstream from one of the body ports. Install the stop valve between the change-over valve and the stem of the center joint.
Other components should be installed according to the layout in the block diagram. The test kit is used to pressurize the center swivel above normal working pressure and lock in the higher pressure (as the stop valve is closed manually) for a leak down test. Relief Valve (1.5x) High Pressure Pump Tank 0370 Figure 2 NOTE: The same type of kit can also be made up for the drain port (return line) side of the center joint. Use appropriate piping, connectors, test gauges, etc., and follow the same block diagram general layout (Figure 2). S0704090K Page 5 Center Joint (Swivel)