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Pumps & Motors
(cont.)
How to INSTALL an entire new pump
Plumbing in a new pump motor...
Cut the pipes going into the front of the
existing (old) pump, and the pipe
coming out of the top. Important: Choose your cut location so as to allow room on
either side of the cut to glue on a repair coupling. Remove the wires and
the
conduit adapter from the rear of the motor. Remove the MTA fittings
threaded into the front and top of the old pump. Using
Teflon tape and
perhaps also
silicone sealant, thread in the fittings you removed from the
old pump. Note: Do Not Over-tighten, turn only 1 1/2 turns past hand tight. Using
rubber mission couplings, PVC unions or simple slip x slip couplings,
reconnect the pipe you cut. On
PVC fittings, use a good primer and good,
fresh
PVC glue for pressure applications.
Wiring up a new pump motor...
First, screw in the conduit adapter onto the
back of the motor. This
adapter is usually removed from the old pump and screwed into the 3/4"
threaded hole where the wires enter the back of the motor. Some motors offer
an additional port of entry on the top for wiring flexibility. Remove the
back of the motor and run the wires in through the adapter, and tighten down
the threaded connector to secure the wires and keep out moisture and
insects. Notice where the wires enter the back of the motor, on the right
side, a terminal board that has 2 brass screws for clamping down the 2
wires (lines) coming in. It doesn't matter which wire goes to which screw.
Above the terminal board, there is a green screw that is for clamping down
the ground wire.
All pump motors are wired to receive 230 Volts from the factory. That is, 2
lines (wires) carrying 115 Volts each. So, you need to know if you have 115
Volts coming in, or if it's 230 Volts. Usually 230 Volt service will have 2
wires of the same color, (and one green ground wire), while 115 Volt service
will have perhaps one red (hot), one white (neutral), and one green. You
should use a meter to be sure, but you could just look at the breaker. If 2
of the wires come off of one breaker, then you have 230 Volts. If one is
connected to a breaker, and the other to the 'neutral' Buss bar, then it is
115 Volt service. Or look at the voltage plate on the old motor and see how it
was hooked up. Is it matching the Low Voltage diagram (115 Volt), or matching the
high voltage diagram (230 Volt)?
If you have 230 Volt service, hook up the wires coming into the motor to the
brass terminals described above. If you have 115 Volt service, follow the
instructions on the motor label to switch the motor to receive 115 Volt. This
is a very easy switch of only one wire. Again, the motor comes factory wired
for 230 Volt. If you are connecting 115 Volts to it, then switch the motor first.
Putting 230 Volts into a 115 Volt motor can damage the windings, and perhaps fail
the motor. After switching the motor to 115 Volts, connect the power wires
to the brass terminals as described above (again it doesn't matter which
wire goes to which screw).
Replacing the motor
(not the plastic wet end, just the motor)
Having learned how to remove and break down
a pump and motor in the previous sections, replacing any of the components is simply a
matter of disassembling the pump down to the component that needs replacement, getting a
replacement part, and reassembling the unit. Of course, if the entire pump and motor is to
be replaced, you purchase the replacement as a unit and plumb it in as previously
described.
Sometimes the motor will trip the circuit
breaker when you try to start it. If this happens it is usually because there is something
wrong with the motor; however, it could be a bad breaker or one that is simply undersized
for the job and has finally worn out. To replace the motor here is the procedure:
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Break down the unit as described in the
section on changing a seal. Remove the shaft extender by removing the Allen-Head setscrews
and pulling the extender off the motor shaft. Sometimes this might need persuasion. Use
your large flat-blade screwdriver to pry the extender away from the motor body. Sometimes
corrosion will eat away at the setscrews and extender - if it is too tough to remove,
replace it.
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Before sliding the shaft extender on the new
motor, clean the motor shaft with a fine emery cloth such as you might have in your copper
pipe solder kit. Apply a light coat of
silicone lube to the shaft. When you put the
extender on the motor shaft, the setscrews go into a groove that runs along the shaft.
This groove allows the screws to grip and not slide around the shaft.
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Now slide the new extender in place, lining
up the setscrews along the channel, but do not tighten the setscrews. When you have
reassembled the bracket and seal plate, seal, and impeller, you can adjust the impeller to
just barely clear the seal plate face, then tighten the setscrews. Be sure the impeller is
screwed tightly onto the shaft extender before making this adjustment. If it is loose,
when the motor starts it will tighten the impeller, by turning it tighter against the
extender, thereby tightening it against the seal plate, seizing up the unit.
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Secure the shaft extender with your pliers or
3/8 - inch box wrench and lay a rag over the impeller. Firmly hand tighten it. Reassemble
the remaining pump parts and/or re-plumb the entire unit back into place.
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Follow wiring instructions above, in previous
section on installing new pumps.
Lubrication...
I always try to stress to pool owners
that a lot of air in the pump or loss of
prime problems are due to lack of
lubrication on the pump lid o-ring.
Lubricants like
Magic Lube (Teflon
based) or Jack's Lube are always a great
choice. Remember that a little dab will
do the job. Never use a petroleum based
product (i.e. Vaseline) for lubrication
on o-rings. Inspect the pump o-ring for
cracks, splits, or pinch marks. Finding
little problems can prevent big problems
from occurring.
All pumps have seals to
prevent water from leaking out along the
motor shaft. When these wear out due to
overheating, vibration or a sudden
change in water pressure - you will need
to replace your
pump shaft seal. The first thing to do is to turn off the electricity to the motor at the
breaker.
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To access this seal for replacement, remove
the four bolts that hold the pump halves together, it is not necessary to remove the
entire pump from the plumbing system.
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Grasp the motor and pull it and the bracket
away from the pump volute. Wiggle it slightly from side to side as you pull back to help break
this joint.
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