User Manual

Pump Motors
47
A.O.Smith
When ordering parts refer to the catalog number
or model number and serial number on the motor
nameplate.
All A.O.Smith motors have some method of
locking the shaft so the impeller can be removed.
Do not stick a screwdriver into the vent holes to
prevent the cooling fan from turning to lock up
the shaft. Some fans are plastic and will break.
Two compartment designs have a flat on the
shaft under the governor assembly. It can be
accessed by carefully sliding a 7/16” open-end
wrench under the protector at 12 O’clock until it
drops over the flats on the shaft.
Older Century Centurion models have flats on
the rear end of the shaft. Access to the flatted
portion of the shaft is achieved by removing a
small metal cover on the rear end frame with a
screwdriver.
Current Century Centurion models have a
plastic cover that can be removed by turning it
1/4 turn counterclockwise with a 15/16” wrench
and pulling out. The end of the flatted shaft
extends out from the rear of the motor. The shaft
can be locked using a 1/2” wrench .
Century Flex 48 motors have a screwdriver slot
or a hex hole (that requires a 5/16” hex socket
wrench) on the end of the shaft.
Impeller
Removal