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D10-991-2400B
D/G-10 Troubleshooting
Cavitation
• Inadequate fluid supply because:
— Inlet line collapsed or clogged
— Clogged line strainer
— Inlet line too small or too long
— Air leak in inlet line
— Worn or damaged inlet hose
— Suction line too long
— Too many valves and elbows in inlet line
• Fluid too hot for inlet suction piping system.
• Air entrained in fluid piping system.
• Aeration and turbulence in supply tank.
• Inlet vacuum too high (refer to the Inlet Calculations
paragraph of the Installation Section).
Symptoms of Cavitation
• Excessive pump valve noise
• Premature failure of spring or retainer
• Volume or pressure drop
• Rough-running pump
• Premature failure
• Piston return spring failure
Drop in Volume or Pressure
A drop in volume or pressure can be caused by one or more
of the following:
• Air leak in suction piping
• Clogged suction line or suction strainer
• Suction line inlet above fluid level in tank
• Inadequate fluid supply
• Pump not operating at proper RPM
• Relief valve bypassing fluid
• Worn pump valve parts
• Foreign material in inlet or outlet valves
• Loss of oil prime in cells because of low oil level
• Ruptured diaphragm
• Cavitation
• Warped manifold from over pressurized system
• O - r i n g s f o r c e d out o f t h e ir g r o ove s from ove r-
pressurization
• Air leak in suction line strainer or gasket
• Cracked suction hose.
• Empty supply tank
• Excessive aeration and turbulence in supply tank
• Worn and slipping drive belts
• Worn spray nozzles
• Cracked cylinder casting
Pump Runs Rough
• Worn pump valves
• Air lock in outlet system
• Oil level low
• Wrong weight of oil for cold operating temperatures
(change to lighter weight)
• Cavitation
• Air in suction line
• Restriction in inlet/suction line
• Hydraulic cells not primed after changing diaphragm
• Foreign material in inlet or outlet valve
• Damaged diaphragm
• Fatigued or broken valve spring
• Broken piston return spring
Premature Failure of Diaphragm
• Frozen pump
• Puncture by a foreign object
• Elastomer incompatible with fluid being pumped
• Pump running too fast
• Excess pressure
• Cavitation
• Broken piston return spring
Water (or Process Fluid) in Oil
Reservoir
• Condensation
• Ruptured diaphragm
• Hydraulic cell not properly primed after diaphragm
replacement
• Frozen pump
• Diaphragm screw O-ring missing or cracked
• Cracked cylinder casting
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