WDM AG Series Operation Manual page 13

Self-Priming Pumps.
ATTENTION.
Do not pry the flange off, but rather bump it off with a block
of wood and a hammer. Pull off the gasket together with the weights,
round head screw and lockwasher. All parts should be examined and
parts showing wear or damage should be replaced. When replacing the
gasket and weight assembly onto the pump body, make sure that the
hinge section of the gasket is at the top and that the large weight is on
the pump side of gasket.
Body, volute and impeller service.
To clean out or repair the body, volute or impeller, disconnect
suction and discharge piping.
Remove the hex nuts and lockwashers and pull the body from the
intermediate coupling. This will expose the O-ring, impeller, impeller
locking screw, volute and volute gasket. Examine all parts for wear
and tear and replace as necessary.
If the impeller needs t o b e replaced, pull volute from intermediate
coupling, remove set screw or cap screws and washers, and
unscrew the impeller from the motor shaft. As the impeller is
screwed onto the shaft with right hand thread, break loose by placing
a block of wood against a vane and striking it with a hammer.
When reassembling, be sure to use the required number of shims to
result in an impeller-to-volute clearance of not more than .021".
Shaft seal service.
When examining or replacing the shaft seal, remove the body and
impeller, impeller shims and rotating member of shaft seal from motor
shaft. This exposes all components of the shaft seal so they can be
examined. When any part shows wear and tear or damage, the
entire shaft seal assembly should be replaced. If a stationary member
needs replacing, pry t h e used stationary member from the
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