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5. Wrong direction of rotation — Com-
pare pump rotation with arrow on
pump. Standard pumps rotate in a
clockwise direction when looking at the
shaft extension end or from the motor
end on close coupled pumps. Reverse
two leads on a three phase motor to
change rotation. Check motor
nameplate for single phase operation.
6. Clogged suction line, strainer, or foot
valve — Inspect and clean out if
necessary.
7. Air pocket in suction line — Look for
high spots in inlet piping system.
Evacuate the system with a vacuum
pump if necessary.
5B Reduced Capacity
1. Pump not up to speed — Use a
tachometer to determine actual RPM.
Check voltage and wiring connections.
2. Excessive suction lift — Relocate
pump, supply tank, or both to minimize
suction lift.
3. Insufficient NPSH — Relocate pump,
supply tank, or both to improve NPSH
available if possible. Increase suction
pressure. Reduce fluid temperature.
Select a pump with lower NPSH
requirements.
4. Mechanical damage — Rotate the
pump by hand to determine if there
are tight spots. Broken or bent
impeller vanes can sometimes be
detected in this manner. If there is a
suspicion of damage, remove the
pump from service and disassemble
for inspection.
5. Air leak in the suction line — Fill the
system with fluid and hydrostatically
test. Tighten connections or replace
leaky components.
6. Air pockets in the suction piping —
Operating the system at maximum
flow conditions will usually clear the
lines. Evacuate the system with a
vacuum pump if necessary.
7. Suction lines, strainer, or foot valve
too small or clogged — Inspect and
clean out as necessary. Fittings and
lines should be at least equal to the
pump suction size.
8. Discharge head too high — Install a
pressure gauge at the pump
discharge to determine the actual
operating pressure. Compare
readings with pump performance
curve. A larger pump may be
necessary.
9. Excessive wear — If a pump had
previously performed satisfactorily
FLEXIBLE COUPLED PUMPS
CLOSE COUPLED PUMPS
VERTICAL FLANGE MOUNTED PUMPS
A. Failure to Pump
B. Reduced Capacity
C. Reduced Pressure
D. Pump Loses Prime After Starting
E. Excessive Power Consumption
F. Pump Vibrates or is Noisy
G. Mechanical Problems
H. Seal Leakage
5A Failure to Pump
1. Pump not up to speed — Use
Tachometer to determine actual
RPM. Check voltage and wiring
connections.
2. Pump not primed — Confirm that
pump and all inlet piping is filled with
fluid.
3. Discharge head too high — Install a
pressure gauge at the pump
discharge to determine the actual
operating pressure. Compare
readings with pump performance
curve. A larger pump may be
necessary.
4. Excessive suction lift — Relocate
pump, supply tank, or both to
minimize suction lift.
5.
T41 SERIES
Troubleshooting
3. Install the snap ring (#4) in the pump
end of the pedestal. Be sure the
snap ring is seated properly in the
groove. The beveled edge of the
ring should face away from the
bearing.
4. Install the flinger over the snap ring.
The bearing pedestal is now ready
for pump and motor installation.
*Alternate bearing installation
procedures.
If an arbor press is not available, the
bearings may be installed on the shaft
using the following procedure:
This procedure is not recommended
and should only be used in an emer-
gency situation.
1. Stand a piece of 3/4" pipe for P3 or
a 1-1/4" piece of pipe for P15, with
the threads cut off, on a workbench
or similar flat surface, with the
bearing placed on the correct shaft
end.
2. Insert the shaft into the pipe so the
bearing is between the pipe and the
shoulder of the shaft. Refer to Figure
4-25.
assembly turns freely. Turn the shaft
by hand. If it is tight or rough spots
are encountered, it is likely that at
least one of the bearings was
damaged during disassembly/
assembly operations, and will have
to be replaced.
2. Look to make sure that the lip seals
on the bearings are positioned
properly in their grooves. Correct if
necessary. As the bearings are
turned, the grooves should appear
wet with oil, but have no visible
grease present.
3. Recheck the snap ring on the large
bearing end. It should be firmly in
place, and no axial motion should
result from gentle tapping on either
end of the shaft. (Use a soft mallet
so shaft surfaces are not damaged.)
4. No adjustments are possible or
required. Proceed with the appropri-
ate pump end assembly operations.
Refer to Section 4 SERVICE -
PUMP ENDS (Final testing is done
after the pump end is in place.)
Figure 4-25
3. Using extreme caution, gently tap on
the end of the shaft until the bearing
rests against the shoulder. Never
attempt to install the bearings by
striking the outer race.
4. Repeat steps 1-3 for the other bearing.
4E Testing and Final Adjustments
1. Check to be sure that the rotating
