18 D04-991-2400 5/1/04
Valve Wear
• Normal wear from high-speed operation
• Cavitation
• Abrasives in the fluid
• Valve incompatible with corrosives in the fluid
• Pump running too fast
Loss of Oil
• External seepage
• Rupture of diaphragm
• Frozen pump
• Worn shaft seal
• Oil drain piping or fill cap loose.
• Valve plate and manifold bolts loose
• Pump housing porosity
Premature Failure of Valve
Spring or Retainer
• Cavitation
• Foreign object in the pump
• Pump running too fast
• Spring/retainer material incompatible with fluid being
pumped
• Excessive inlet pressure.
D/G-04 Troubleshooting