PROBLEM
POSSIBLE CAUSE
Pump wont prime Suction line problem
Leaky check valves
Check valves improperly installed Check for proper installation.
Outlet plugged
Motor not operating
Stripped or damaged gears
Pump hums but will Motor faulty
not operate
Gear mechanism jammed
Low pump capacity Low voltage
Leaky suction line
Dirt in check valves
Faulty check valves
One or both diaphragms leaking Install repair kit.
One piston screw loose
Piston retainer screws loose
Debris ingested
Motor overheats
Pumping hot fluids
Motor faulty
Fluid leakage
Faulty or missing gaskets
Loose bolts
Cracked component
Piston retainer screws loose
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SOLUTION
Check for leaks in suction line.
Check for dirt or damaged check valves and replace.
Check for blockage and clear.
Check power source.
Repair or replace motor.
Check gear assembly and drive gear for damage.
Replace complete assembly if necessary.
Replace motor.
Check for free rotation of the gears.
Check power source.
Repair leaks.
Dismantle and clean.
Install repair kit.
Install new yoke assembly.
Install new yoke assembly.
Add inlet screen.
Shorten duty cycle.
Replace motor.
Install all gaskets specified in parts list.
Torque all bolts to 50 in. lbs.
Replace defective component.
Install new yoke assembly.
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