Wilo American-Marsh Pumps SXT-3"X3" User manual

490 Series SXT 3”x3”
Self-Priming Pumps
Installation and Operating Manual
*077-0238-000*

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IOM 490 SXT 3”X3”_1222
TABLE OF CONTENTS
INTRODUCTION .............................................................................................................................. 3
SAFETY SECTION A ......................................................................................................................... 5
INSTALLATION SECTION B .............................................................................................................. 6
Pump Dimensions ............................................................................................................... 6
PREINSTALLATION INSPECTION ............................................................................................... 7
POSITIONING PUMP .................................................................................................................. 7
Lifting ................................................................................................................................. 7
Mounting ............................................................................................................................ 7
Clearance ........................................................................................................................... 7
SUCTION AND DISCHARGE PIPING ........................................................................................... 8
Materials ............................................................................................................................. 8
Line Configuration ............................................................................................................. 8
Connections to Pump ......................................................................................................... 8
Gauges ................................................................................................................................ 8
SUCTION LINES ......................................................................................................................... 8
Fittings ............................................................................................................................... 8
Strainers ............................................................................................................................. 8
Sealing ................................................................................................................................ 9
Suction Lines In Sumps ...................................................................................................... 9
Suction Line Positioning .................................................................................................... 9
DISCHARGE LINES ................................................................................................................... 10
Siphoning ......................................................................................................................... 10
Valves ............................................................................................................................... 10
Bypass Lines ..................................................................................................................... 11
AUTOMATIC AIR RELEASE VALVE .......................................................................................... 11
Theory of Operation ......................................................................................................... 11
ALIGNMENT ............................................................................................................................ 13
Coupled Drives ................................................................................................................. 13
Drive Belts ........................................................................................................................ 14
OPERATION SECTION C ................................................................................................................ 15
PRIMING .................................................................................................................................. 15
STARTING ............................................................................................................................... 15
Rotation ........................................................................................................................... 15
OPERATION ............................................................................................................................ 16
Lines With a Bypass .......................................................................................................... 16
Lines Without a Bypass .................................................................................................... 16
Leakage ............................................................................................................................ 16
Liquid Temperature And Overheating ............................................................................. 16
Strainer Check .................................................................................................................. 17
Pump Vacuum Check ....................................................................................................... 17

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IOM 490 SXT 3”X3”_1222
STOPPING ............................................................................................................................... 17
Cold Weather Preservation .............................................................................................. 17
BEARING TEMPERATURE CHECK ............................................................................................ 18
TROUBLESHOOTING SECTION D ................................................................................................... 18
PREVENTIVE MAINTENANCE .................................................................................................. 20
PERFORMANCE CURVE ........................................................................................................... 22
ILLUSTRATION ........................................................................................................................ 23
PARTS LIST ............................................................................................................................. 24
PUMP AND SEAL DISASSEMBLY AND REASSEMBLY ............................................................... 25
Back Cover and Wear Plate Removal ............................................................................... 25
Suction Check Valve Removal ......................................................................................... 26
Rotating Assembly Removal ............................................................................................ 26
Impeller Removal ............................................................................................................. 27
Seal Removal .................................................................................................................... 28
Shaft and Bearing Removal and Disassembly .................................................................. 28
Shaft and Bearing Reassembly and Installation ............................................................... 29
Seal Installation ................................................................................................................ 30
Impeller Installation and Adjustment .............................................................................. 33
Rotating Assembly Installation ........................................................................................ 33
Suction Check Valve Installation ..................................................................................... 34
Back Cover and Wear Plate Installation and Adjustment ................................................ 34
PRESSURE RELIEF VALVE MAINTENANCE .............................................................................. 36
Final Pump Assembly ....................................................................................................... 36
LUBRICATION ......................................................................................................................... 36
Seal Assembly .................................................................................................................. 36
Power Source ................................................................................................................... 37
WARRANTY ................................................................................................................................... 38

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IOM 490 SXT 3”X3”_1222
INTRODUCTION
Thank You
for purchasing an American-Marsh Pump. Read this manual carefully to learn how to
safely install and operate your pump. Failure to do so could result in personal injury or damage to the
pump.
Because pump installations are seldom identical, this manual cannot possibly provide detailed
instructions and precautions for every aspect of each specific application. Therefore, it is the
responsibility of the owner/installer of the pump to ensure that applications not addressed in this
manual are performed only after establishing that neither operator safety nor pump integrity are
compromised by the installation. Pumps and related equipment must be installed and operated
according to all national, local and industry standards.
If there are any questions regarding the pump or its application which are not covered in this manual
or in other literature accompanying this unit, please contact your AMP distributor:
American-Marsh Pumps
550 E. South St.
Collierville, TN 38017
Phone: [phone]
For information or technical assistance on the power source, contact the power source
manufacturer's local dealer or representative.
RECORD YOUR PUMP MODEL AND SERIAL NUMBER
Please record your pump model and serial number in the spaces provided below.
Your American-Marsh Pumps (AMP) distributor needs this information when you require parts or service.
Pump Model:
Serial Number:

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IOM 490 SXT 3”X3”_1222
HAZARD AND INSTRUCTION DEFINITIONS
The following are used to alert maintenance personnel to procedures which require special attention,
to those which could damage equipment, and to those which could be dangerous to personnel:
DANGER: Immediate hazards which WILL result in severe personal injury or death. These
instructions describe the procedure required and the injury which will result from failure to
follow the procedure.
WARNING: Hazards or unsafe practices which COULD result in severe personal injury or
death. These instructions describe the procedure required and the injury which could result
from failure to follow the procedure
CAUTION: Hazards or unsafe practices which COULD result in minor personal injury or
product or property damage. These instructions describe the requirements and the possible
damage which could result from failure to follow the procedure
NOTE
Instructions to aid in installation, operation, and maintenance or which clarify a procedure.

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IOM 490 SXT 3”X3”_1222
SAFETY SECTION A
This information applies to the 490 Series SXT 3”x3” pumps. AMP has no control over or particular
knowledge of the power source which will be used. Refer to the manual accompanying the power
source before attempting to begin operation.
This manual will alert personnel to known procedures which require special attention, to those which
could damage equipment, and to those which could be dangerous to personnel. However, this
manual cannot possibly provide detailed instructions and precautions for each specific application
or for every situation that might occur during maintenance of the unit. Therefore, it is the
responsibility of the owner, installer and/or maintenance personnel to ensure that applications
and/or maintenance procedures
NOT addressed in this manual are performed ONLY after
establishing that neither personal safety
NOR pump integrity are compromised by such applications
or procedures.
This pump is designed to handle most non ‐ volatile, non ‐ flammable liquids containing
specified entrained solids. DO NOT attempt to pump volatile, corrosive, or flammable
materials which may damage the pump or endanger personnel as a result of pump
failure.
After the pump has been positioned, make certain that the pump and all piping
connections are tight, properly supported, and secure
before operation.
DO NOT operate the pump without the guards in place over the rotating parts. Exposed
rotating parts can catch clothing, fingers, or tools, causing severe injury to personnel.
DO NOT remove plates, covers, gauges, pipe plugs, or fittings from an overheated
pump. Vapor pressure within the pump can cause parts being disengaged to be ejected with great
force. Allow the pump to cool before servicing.
DO NOT operate the pump against a closed discharge valve for long periods of time. If
operated against a closed discharge valve, pump components will deteriorate, and the
liquid could come to a boil, build pressure, and cause the pump casing to rupture or
explode.
Death or serious personal injury and damage to the pump or components can occur if proper
lifting procedures are not observed. Make certain that hoists, chains, slings, or cables are in good
working condition and of sufficient capacity and that they are positioned so that loads will be
balanced, and the pump or components will not be damaged when lifting. Suction and discharge
hoses and piping must be removed from the pump before lifting. Lift the pump or component
only as high as necessary and keep personnel away from suspended objects
.

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IOM 490 SXT 3”X3”_1222
INSTALLATION SECTION B
Review all SAFETY information in Section A.
Since pump installations are seldom identical, this section offers only general recommendations and
practices required to inspect, position, and arrange the pump and piping.
Most of the information pertains to a standard static lift application where the pump is positioned
above the free level of liquid to be pumped.
If installed in a flooded suction application where the liquid is supplied to the pump under pressure,
some of the information such as mounting, line configuration, and priming must be tailored to the
specific application. Since the pressure supplied to the pump is critical to performance and safety,
be sure to limit the incoming pressure to 50% of the maximum permissible operating pressure as
shown on the pump performance curve.
For further assistance, contact your AMP distributor.
Pump Dimensions
See Figures 1 for the approximate physical dimensions of the pump.
OUTLINE DRAWING
Figure 1. Pump Model SXT-3”X3”

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IOM 490 SXT 3”X3”_1222
PREINSTALLATION INSPECTION
The pump assembly was inspected and tested before shipment from the factory. Before installation,
inspect the pump for damage which may have occurred during shipment. Check as follows:
a.
Inspect the pump for cracks, dents, damaged threads, and other obvious damage.
b.
Check for and tighten loose attaching hardware. Since gaskets tend to shrink after drying, check
for loose hardware at mating surfaces.
c.
Carefully read all warnings and cautions contained in this manual or affixed to the pump, and
perform all duties indicated. Note the direction of rotation indicated on the pump. Check that
the pump shaft rotates counterclockwise when facing the impeller.
Only operate this pump in the direction indicated by the arrow on the pump body and on
the accompanying decal. Refer to ROTATION in OPERATION, Section C.
d. Check levels and lubricate as necessary. Refer to LUBRICATION in the MAINTENANCE AND
REPAIR section of this manual and perform duties as instructed.
e.
If the pump and power source have been stored for more than 12 months, some of the
components or lubricants may have exceeded their maximum shelf life. These must be inspected
or replaced to ensure maximum pump service.
If the maximum shelf life has been exceeded, or if anything appears to be abnormal, contact your
AMP distributor to determine the repair or updating policy. DO NOT put the pump into service until
appropriate action has been taken.
POSITIONING PUMP
Lifting
Pump unit weights will vary depending on the mounting and drive provided. Check the shipping tag
on the unit packaging for the actual weight, and use lifting equipment with appropriate capacity.
Drain the pump and remove all customer
‐ installed equipment such as suction and discharge hoses
or piping before attempting to lift existing, installed units.
Death or serious personal injury and damage to the pump or components can occur if
proper lifting procedures are not observed. Make certain that hoists, chains, slings or
cables are in good working condition and of sufficient capacity and that they are
positioned so that loads will be balanced, and the pump or components will not be
damaged when lifting. Suction and discharge hoses and piping must be removed from the pump
before lifting. Lift the pump or component only as high as necessary and keep personnel.
Mounting
Locate the pump in an accessible place as close as practical to the liquid being pumped. Level
mounting is essential for proper operation.
The pump may have to be supported or shimmed to provide for level operation or to eliminate
vibration
Clearance
It is recommended that
18 inches (457 mm) of clearance be provided in front of the back cover to

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IOM 490 SXT 3”X3”_1222
permit removal of the cover and easy access to the pump interior. A minimum clearance of 9 inches
(229 mm)
must be maintained to permit removal of the cover.
SUCTION AND DISCHARGE PIPING
Pump performance is adversely affected by increased suction lift, discharge elevation, and friction
losses. See the performance curve and operating range shown in
SECTION E to be sure your overall
application allows pump to operate within the safe operation range.
Materials
Either pipe or hose maybe used for suction and discharge lines; however, the materials must be
compatible with the liquid being pumped. If hose is used in suction lines, it must be the rigid
‐ wall,
reinforced type to prevent collapse under suction. Using piping couplings in suction lines is not
recommended.
Line Configuration
Keep suction and discharge lines as straight as possible to minimize friction losses. Make minimum
use of elbows and fittings, which substantially increase friction loss. If elbows are necessary, use the
long
‐ radius type to minimize friction loss.
Connections to Pump
Before tightening a connecting flange, align it exactly with the pump port. Never pull a pipeline into
place by tightening the flange bolts and/or couplings.
Lines near the pump must be independently supported to avoid strain on the pump which could
cause excessive vibration, decreased bearing life, and increased shaft and seal wear. If hose
‐ type
lines are used, they should have adequate support to secure them when filled with liquid and under
pressure.
Gauges
Most pumps are drilled and tapped for installing discharge pressure and vacuum suction gauges. If
these gauges are desired for pumps that are not tapped, drill and tap the suction and discharge lines
not less than 18 inches (457,2 mm) from the suction and discharge ports and install the lines.
Installation closer to the pump may result in erratic readings.
SUCTION LINES
To avoid air pockets, which could affect pump priming, the suction line must be as short and direct
as possible. When operation involves a suction lift, the line must always slope upward to the pump
from the source of the liquid being pumped; if the line slopes down to the pump at any point along
the suction run, air pockets will be created.
Fittings
Suction lines should be the same size as the pump inlet. If reducers are used in suction lines, they
should be the eccentric type, and should be installed with the flat part of the reducers uppermost to
avoid creating air pockets. Valves are not normally used in suction lines, but if a valve is used, install
it with the stem horizontal to avoid air pockets.
Strainers
If a strainer is furnished with the pump, be certain to use it; any spherical solids which pass through
a strainer furnished with the pump will also pass through the pump itself.

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IOM 490 SXT 3”X3”_1222
If a strainer is not furnished with the pump, but is installed by the pump user, make certain that the
total area of the openings in the strainer is at least three or four times the cross section of the suction
line, and that the openings will not permit passage of solids larger than the solids handling capability
of the pump.
This pump is designed to handle up
to 2-1/2-inch (63,5 mm) diameter spherical solids.
Sealing
Since even a slight leak will affect priming, head, and capacity, especially when operating with a high
suction lift, all connections in the suction line should be sealed with pipe dope to ensure an air-tight
seal. Follow the sealant manufacturer's recommendations when selecting and applying the pipe
dope. The pipe dope should be compatible with the liquid being pumped.
Suction Lines In Sumps
If a single suction line is installed in a sump, it should be positioned away from the wall of the sump
at a distance equal to 1 1/2 times the diameter of the suction line.
If there is a liquid flow from an open pipe into the sump, the flow should be kept away from the
suction inlet because the inflow will carry air down into the sump, and air entering the suction line
will reduce pump efficiency.
If it is necessary to position inflow close to the suction inlet, install a baffle between the inflow and
the suction inlet at a distance 1 1/2 times the diameter of the suction pipe. The baffle will allow
entrained air to escape from the liquid before it is drawn into the suction inlet.
If two suction lines are installed in a single sump, the flow paths may interact, reducing the efficiency
of one or both pumps. To avoid this, position the suction inlets so that they are separated by a
distance equal to at least 3 times the diameter of the suction pipe.
Suction Line Positioning
The depth of submergence of the suction line is critical to efficient pump operation. Figure 2 shows
recommended minimum submergence vs. velocity.
NOTE
The pipe submergence required may be reduced by installing a standard pipe increaser fitting at the
end of the suction line. The larger opening size will reduce the inlet velocity. Calculate the required
submergence using the following formula based on the increased opening size (area or diameter).