MP Pumps S300, S600, S700, FM40 User Manual

Instruction Bulletin

Series 300, 700, and FLOMAX 40 PUMPS

MOUNTING THE PUMP - Close-coupled

pumps are assembled into a rigid unit and
should be bolted down securely. The close­coupled pump can be mounted in any posi­tion. However, when mounted in other than
horizontal position, the pump motor must be
located above the pump so that liquid leak­age will not damage the motor.

Pedestal or foot mounted pumps with grease
lubricated bearings can be mounted in any po­sition. The bearing housing must be above
the pump in any non-horizontal application to
prevent bearing damage due to liquid leakage.
The pedestal or foot mounted pumps, when
provided with driver and a coupling, are
mounted on a steel base plate which accom­modates both pump and driver. Although the

components have been aligned accurately
at the factory, the alignment must be re­checked after the unit has been set in place
at the job site.

PIPING - Do not allow the pump to carry the

weight of piping. Both suction and discharge
piping should be supported independently at
a point near the pump. Piping must be installed
carefully so that it will not be necessary to force
it into place when connecting to the pump.
Use slip joints or flexible connectors where long
discharge lines are being used or lines that
are subject to wide temperature ranges. Flex­ible connectors also help to prevent transmis­sion of noise and vibrations.

Also a careful check must be made to be sure
that the pump’s required net positive suction
head (NPSH
line draws liquid from an open sump, its lower
end should be submerged sufficiently so that air
is not drawn into the line by vortex action.

If a reducer is used between piping and pump,

reducer should be eccentric type with the flat side
on top to prevent air from being trapped in the
suction line. Piping should always slope up to
the pump with no high spots to trap air.

DISCHARGE PIPING - To minimize friction
losses, care should be taken in sizing, layout,
number of fittings, etc. of discharge pipeline. A
gate valve should be installed in discharge line
to control pump flow and to allow servicing of
pump without having to drain the discharge line
and any connected vessels. The discharge valve
should be open during self-priming start-up for
the FLOMAX 40.

START UP:

Centrifugal pumps must be primed before they
will start pumping. Fill the suction line and pump
and enough of the discharge line to establish a
liquid level one or two feet above the top of the
pump case. Turn the pump shaft by hand so
that air trapped within the immpeller can escape.

R) is available. When the suction

SUCTION PIPING - Place pump as close to

the liquid source as possible. The suction line
should be short, and large, with as few fittings
as possible and with smooth long radius el­bows, where space permits, to keep friction
loss at a minimum. When necessary, a good
strainer or foot valve for priming should be
used. A valve is usually included in the suc­tion line to facilitate servicing the pump. Suc­tion piping must be absolutely free of leaks.

The FLOMAX 40 is a self-priming pump. The
pump case must be filled with water for initial
start-up. The suction line of this pump does not
have to be filled as the pump will evacuate the
air from the line when it performs its self-priming
function.

Make sure that the gate valve between the suc­tion of the pump and the source of supply is open.

FORM 3021-D (10/04)

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IMPORTANT:

Check for correct direction of rotation of
prime-mover. Check rotation of three phase

motors by turning on power only for an instant
so that pump

longed operation of pump in wrong direction may
damage it). If direction is wrong, reverse rotation
by interchanging any two of the three wires, ei­ther at the motor or electric starter , in a three phase

electrical system.

Close gate valve in discharge line and start pump.
Open valve gradually to half-open position after driver
attains full speed. If pump fails to function after a few
seconds of operation, stop it, add more priming liquid
if needed, and let air escape completely. Restart the
pump.

FLOMAX 40, as a self-priming pump, requires that
the discharge valve be in the fully open position on
start-up to permit the air in the suction line to be ex­pelled into the discharge line. Failure to open the dis­charge line will prohibit the pump from priming itself.
Self-priming requires a minute or more for the pump
to evacuate the air from the suction before pumping
begins.

turns just a few revolutions (pro-

There are two possible causes for leaks along the pump
shaft:

1. The impeller sealing gaskets could be worn or de­ fective causing leakage through the sleeve.(See Fig­ ure1). When the pump is operating this leakage can
be detected by visual inspection of the juncture be­ tween sleeve and the shoulder on the pump shaft.

2. A worn or defective seal. In most cases, a seal
leak will be a much higher capacity leak than that
of a leak underneath the sleeve. In addition, it will
be evident that leakage is coming out along the shaft
from underneath the seal.

As the pump is disassembled, carefully check the parts
to determine if the leakage was through the impeller seal­ing gaskets rather than the seal. The removal proce­dure outlined below may result in the destruction of the
seal and should not be used unless it is definitely estab­lished that the seal is leaking.

ST ANDARD AND SEVERE SERVICE SEAL CHANGE
PROCEDURE:

Remove the pump housing as follows:

1. Remove the housing capscrews.

Do not permit the pump to run for more than a few
seconds unless it remains full of liquid and is discharg­ing properly. Prolonged operation of an unprimed
pump can cause severe damage to rotating parts.

If the pump must be shut down after initial start up
while exposed to below freezing weather, protect it
and connected piping from damage by draining the
system completely or by introducing a corrosion in­hibiting antifreeze to the system.

SERVICE AND MAINTENANCE INSTRUCTIONS

When seal maintenance is required, they can be ser­viced by leaving the housing in the piping. All pumps
have back pull out design. Jackscrews are provided
to assist in removing the housing and seal cover.

NOTE:

A lifting eye is provided to lift the pump only. This
should not be used to lift the electric motor, base,
and pump assembly.

The following instructions assume the entire pump has
been removed from the piping and is on a bench to be
serviced. The instructions for back pullout are the
same with the exception that the two bolts holding the
bearing assembly to the rear support bracket should
be removed allowing the bearing adaptor, impeller,
and shaft assembly to be removed in the back pullout
mode. Refer to proper parts list.

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2. Using the outer set of jackscrews start the removal
of the housing. If the screws are missing use two of
the capscrews removed from the housing. The jack­ screws are not long enough to completely disengage
the housing from the adaptor.

Remove the impeller as follows:

1. Hold impeller with a small pry bar or piece of hard
wood in the discharge of the impeller.

2. Remove seal bolt with 3/4” socket. Also remove
stainless steel and Teflon sealing washers and O-ring,

3. Slide the impeller off the shaft. It may be necessary
use two small pry bars or large screwdrivers behind
the impeller to break it loose.

The seal head will frequently set up on the sleeve so
that it cannot be easily removed by hand. If this occurs,
it will be necessary to use the seal cover to assist in
removing the seal head from the sleeve as follows:

1. Remove the two capscrews holding the seal cover in
place.

2. Use the two jackscrews to start removal of the seal
cover.

3. When the jackscrews have been moved to the limit
the seal cover can be removed by hand. This will
remove the seal from the pump. In the event the
seal is firmly attached to the sleeve, the shaft sleeve
may also be removed with this procedure.