msb2dl3sm-REV0317
Model MSB2 Page 5
PROBLEM: Pump will not cycle. (Note: Always disconnect air supply to relieve air
pressure before disassembling any portion of pump.)
POSSIBLE CAUSES:
A. Discharge hose or line plugged, or discharge head requirement greater than air
supply pressure. (Disconnect discharge line to check.)
B. Spool in air distribution valve not shifting. (Remove end cap and check spool —
must slide freely.)
C. Diaphragm ruptured. (Air will escape out discharge line in this case.)
D. Blockage in diaphragm chamber preventing movement. (Shut off air supply and
reopen after pressure is relieved.)
PROBLEM: Uneven discharge flow. (Indicates one chamber not operating properly.)
POSSIBLE CAUSES:
A. Check valve not sealing properly in one chamber.
B. Diaphragm failure in one chamber.
C. Air leak at suction manifold joint or elbow flange one side.
For additional information, see the Warren Rupp Troubleshooting Guide.
WARRANTY:
This unit is guaranteed for a period of five years against defective material and
workmanship.
WARNING
