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4.
Service
T51 SERIES
e. Holding the head assembly
between the thumb and index
finger, with the sealing face
pointing toward the stationary
seat, slide the assembly over
the motor shaft until it rests
against the seat. Refer to
Figure 4-14. A slight twisting
motion will allow the assembly
to slide more easily.
f. Check to see that the head
assembly is against the seat
face.
g. Position the rotating element
spring with the spring holder
resting against the shoulder of
the sleeve hub.
h. Align the keyway slot in the
hub assembly, and the key in
the motor shaft. Refer to
Figure 4-14,
i. Slide the hub and spring
assembly over the shaft until
the hub is properly seated and
the spring is positioned
correctly on the rotating
element head previously
installed. Refer to Figure 4-11
and 4-12.
j. While maintaining inward
pressure on the hub, install
the impeller nut. Refer to
Figure 4-16.
k. Tighten the nut as far as
possible by hand.
l. Pressure can now be re-
leased.
m. To tighten the nut, place a
crescent wrench over the hub
sleeve and engage the drive
key.
n. Place a second crescent wrench
over the nut and tighten in a
clockwise direction until it is
secured. Refer to Figure 4-17.
4. Install the impeller.
a. The impeller is a slip fit and
should slide on firmly but easily
until it stops against the impeller
wearing surface. Force should
not be required to install the
impeller in the correct position.
b. The impeller hub should be facing
out away from the motor bracket.
c. If the impeller does not fit, repeat
steps a. and b. to determine the
problem.
5. Place “O” ring (#7) into the “O” ring
groove in the motor bracket. It is
helpful to stand the motor and pump
assembly on end for this procedure.
6. Place the cover over the studs and
install the two (2) 3/8" nuts and two
(2) 3/8"x4" bolts. Tighten the nuts
and bolts, systematically alternating
diagonally across the cover. Do not
over-tighten the nuts and bolts; final
adjustment will be made after the
unit is in operation.
4G Testing and Final Adjustment
The pump is now ready for installation.
Final adjustments will be made with the
pump in operation.
1. Reconnect the electrical connec-
tions referring to the colored or
numbered tape used to mark the
wires during disassembly.
2. Connect all piping and fill the
pump with fluid.
3. Make sure all valves are open,
and fluid will flow through the
system.
4. Start the pump and make the
final adjustments to the 3/8" nuts
and bolts holding the cover on.
These nuts and bolts must be
torqued to 20 ft. lbs. to obtain
proper performance.
5. Check for leaks on pump and
piping. Special attention should
be given to the seal area at the
rear opening in the motor
bracket.
6. Under pressure, the impeller will
find its “hydraulic” balance.
7. Using an amprobe or similar
device, check for motor overload.
8. While the impeller is seating, it is
common to experience some
variance in readings. After a
run-in period the readings should
level off.
This completes the adjustment and
testing phase. The pump is ready
for service.
Figure 4-15
Figure 4-16
Figure 4-17
