Sandpiper Diaphragm Pump S30B1H1AAAS000.

Is the pump operating or cycling erratically?

Inspect the air exhaust muffler for blockage or icing

Clean or de-ice the muffler screen as required

Is there water in the compressed air supply?

Inspect diaphragm plates for issues

Inspect intermediate bearings for issues

Inspect diaphragm rod for issues

Clean or repair diaphragms if appropriate

Inspect all fasteners for loosening caused by gasket creep

Retighten loose fasteners to recommended torque values

Inspect all suction-side gaskets and pipe connections for air leakage

Check all suction screens or strainers for obstructions

Clear any obstructions from suction screens or strainers

Inspect the air exhaust muffler for blockage, icing, or presence of pumped fluid

Shut off the compressed air line

Disconnect the air line from the pump

Remove plunger, actuator (29) from center of intermediate pilot valve cavity

Remove Ring, Retaining (30) and discard

Inspect bushing, plunger (7) for wear and replace if necessary with genuine parts

Inspect O-Ring (26) for wear and replace if necessary with genuine parts

Inspect check valves and seats for wear and proper setting

Replace check valves and seats if necessary

Disassemble the wet end of the pump

Manually dislodge any obstruction in the check valve pocket

Clean out around the valve ball cage and valve seat area

Replace valve ball or valve seat if damaged