3
Figure 2
Drain Plug
Priming
Plug
Discharge
REPLACING MECHANICAL SEAL:
(Refer to Figure 2)
TO DISASSEMBLE:
For Models up to 2-1/2 HP
(Square fl ange motors)
a)
Remove the bolts (1) and remove the seal plate and
motor assembly from the casing (1).
b)
Remove suction diffuser (2) by prying it off of seal plate.
c)
Unscrew the impeller (5) counter clockwise.
d)
Slip the seal off the shaft.
e)
If the seat (9) needs to be replaced, push it out of the
seal plate from the motor side.
TO REASSEMBLE:
a)
Clean all parts.
b)
Wet rubber part of the seal seat with liquid soap and
press it into its housing in the seal plate or adapter
(smooth ceramic surface facing upwards).
c)
Assemble the seal plate or adap ter to the motor.
d)
Wet the rubber ring of the seal assembly with liquid soap
and slip it onto the motor shaft. Make sure the sealing
face is towards the ceramic seat.
e)
Replace the impeller.
f)
Reassemble to the casing and diffuser ring. It is recom-
mended to use a new gasket (3).
g)
Reconnect the suction and discharge piping and recon-
nect the electrical wiring.
PRECAUTIONS:
a)
Whenever pump is dismantled and then reassembled,
always check to see that the impeller rotates freely
within the casing.
b)
The NSPHE models have a fl inger (10) on the shaft.
This fl inger must not be removed.
TROUBLESHOOTING
PROBLEM
PROBABLE CAUSE
SOLUTION
Failure to pump:
Pump not properly primed.
Make sure pump casing and suction line are full of water. See priming instructions.
Speed too low.
WARNING - ELECTRICAL PRECAUTIONS: All wiring, electrical connections and
system grounding must comply with the National Electrical Code (NEC) and with any
local codes and ordinances. Employ a licensed electrician. Check voltage at motor termi-
nals and at meter when pump is operating. If low, refer to wiring instructions or check with
your power company. Check loose connections.
Total head more than that for which
pump was intended.
A pump designed for higher head needed.
Suction lift is too great.
Locate pump closer to source of water. Make sure suction piping is large enough.
Reduced capacity
and/or head:
Air pockets or leaks in suction line.
Check suction piping.
Clogged impeller.
Remove and clean.
Strainer too small or clogged.
Use larger strainer or clean.
Insufficient submergence of suction line. Add lengths of suction pipe to keep submerged end well below the water surface.
Excessive suction lift.
If caused by suction pipe friction, enlarge piping. Otherwise, move pump closer to water
level.
Total head more than that for which the
pump was intended.
A pump designed for higher head is needed.
Excessively worn impeller.
Order replacement parts using Repair Parts List.
Pump loses
prime:
Air leaks in suction line.
Check suction piping.
Excessive lift and operating too near
shut-off point.
Move pump nearer water level.
Water level drops while pumping,
uncovering suction piping.
Check water supply. Add length of pipe to suction to keep submerged end under
water.
