EBARA GS Series Operating and maintenance manual

End Suction Centrifugal
GS Series
Operating Instructions, Installation & Maintenance Manual
EBARA Pumps Americas Corporation

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EBARA PUMPS AMERICAS CORPORATION
www.pumpsebara.com
(t) 803.327.5005 (f) 803.327.5097 rev. 03/22
End Suction Centrifugal GS Series
Contents
1. INTRODUCTION.....................................................................................................................................4
2. SAFETY.................................................................................................................................................4
2.1 PREPARATION AND TRAINING OF STAFF
2.2 MAINTENANCE
3. TRANSPORT AND STORAGE..............................................................................................................5
4. SPECIFICATIONS..................................................................................................................................5
5. OPERATING LIMITS..............................................................................................................................6
6. INSTALLATION......................................................................................................................................7
6.1 INSTALLATION POINT
6.2 LIFTING
6.3 CEMENTED BASE
6.4 PIPES
6.5 ALIGNMENT
6.6 ELECTRICAL SYSTEM
6.6.1 ELECTRICAL CONNECTION
6.6.2 ELECTRICAL MAINTENANCE
7. OPERATION........................................................................................................................................12
7.1 BEFORE STARTING THE PUMP
7.2 STARTING THE PUMP
7.3 STOPPING THE PUMP
8. MAINTENANCE...................................................................................................................................13
8.1 DAILY INSPECTION
8.2 PRECAUTIONS DURING OPERATION
8.3 PRECAUTIONS DURING STORAGE
8.4 REPLACING PARTS
8.5 TROUBLESHOOTING
8.6 RESIDUAL RISKS
9. CONSTRUCTION.................................................................................................................................20
10. DISMANTLING AND FITTING...........................................................................................................22
11. REPAIR AND WARRANTY................................................................................................................22

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Thank you for choosing this EBARA GS model pump. This operating manual describes the correct
installation, operation and maintenance procedures of the product. EBARA pays great attention to the
manufacturing of its products so that their use by end-users may be as safe as possible. However, using
this pump improperly may reduce its operating performance and lead to personal injury and damage to
property.
All our devices are delivered after being checked at our own plant and so they are in a condition to operate
correctly after being connected to the power supply and the water system, as shown in this manual.
When this device is delivered:
1. Check the nameplates. It is very important to check the voltage rating for the pump. Also, check the
value of the head, the capacity and the Rotation speed of the pumps, as well as the motor output.
2. Double check the equipment to make sure there is no damage generated during the startup and
that there are no loose screws or mountings.
3. Check that all the accessories, spare parts and required options are included within the supply.
We recommend that you keep this manual in a safe place so that it may be consulted whenever needed.
This instruction and maintenance manual includes the basic instructions that should be taken into
consideration during installation, operation and maintenance of the equipment.
Generic Hazard Electrical Voltage
It is essential that the worker/installer reads all the sections in this manual carefully before installation and
operation. We recommend that you keep this manual in the place where you plan to install the equipment.
In addition to the safety instructions found in this manual, it is also necessary to take into account the safety
regulations and standards in force in the country where you want to use the equipment, in order to achieve
greater protection.
Disregarding the safety instructions shown in this manual may lead to risks to persons and equipment.
1. INTRODUCTION
2. SAFETY

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2.1 PREPARATION AND TRAINING OF STAFF
The personnel involved in the installation, operation, maintenance and control of the equipment must
be properly trained so as to carry out their tasks as effectively as possible. The responsibility, skills and
supervision of the personnel fall within the remit of the employer. If the staff do not have the appropriate
knowledge, they must be duly trained. If required, the employer may receive proper training directly from
EBARA or from the distributor of this equipment.
2.2 MAINTENANCE
No technical or structural changes to the equipment are permitted without prior approval from EBARA.
Only genuine spare parts and accessories authorized by EBARA are suitable for meeting safety standards.
Rebuilding, modifying or using other spare parts may lead to the invalidation of your warranty.
Sound operation of the equipment depends on whether it is being used in accordance with the instructions
given in this instruction manual. The working conditions and limits set out in this manual may not be
exceeded in any way.
Always keep the nameplates legible and in good condition because the details shown will be needed for
future reference or to request spare parts.
3. TRANSPORT AND STORAGE
If necessary, the equipment must be handled and stored in appropriate packaging. It must not be stored
in damp environments with strong variations in temperature or in corrosive atmospheres. Condensates
may attack the seal areas, metal parts and its electrical operation. In this case, any claims made under the
warranty will be refused.
4. SPECIFICATIONS
Pump Tag:
1. Product code
2. Serial number
3. Flow rate
4. Head
5. PEI Value
6. Impeller Diameter
7. Motor Model
8. Motor HP
9. Motor Rotational Speed
10. Assembly Date
1.
2.
3. 4.
5. 6.
7.
8. 9.
10.

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Its applications include climate control and building services, water supply, industry, etc. Other specications
are shown in the following table:
Pump body in cast iron ASTM A48 CL35
5. OPERATING LIMITS
Unless EBARA has been previously notied, in general, the equipment must be mounted inside (below roof
level), in adequately ventilated rooms and where access is restricted to authorized personnel, in addition
to working within the following limits:
• Ambient temperature: must not exceed 104°F and the average temperature over 24 hours must
not be above 95°F. The minimum air temperature in the space will be 39°F.
• Humidity: humidity must not exceed 50% and a temperature of 104°F. Higher humidity levels can
be accepted at very low temperatures.
• Pollution: the air inside the aforesaid space must be clean and non-corrosive or, failing that, the
pollution level must be low and electrically non-conductive through condensation.
• Altitude: the altitude where the pump is installed must not exceed 1000m/3300ft.
If the conditions of use are di󰀨erent from those indicated, EBARA must be notied of these conditions; such
as installation outdoors or in places open to the public; any temperature, humidity, and altitude values other
than those described; heavy pollution due to dust, fumes, vapors or salt; exposure to strong magnetic or
electrical elds; locations exposed to risks of explosion, mechanical vibrations and signicant shocks.
Standard
2 and 4 poles
Temperature
14 to 176ºF
in accordance with
requirements
in accordance with
requirements
200 PSI (13.8 Bar)
Impeller
Closed
Mechanical
Carbon/Ceramic
Bearings
Shielded ball bearings
ANSI B16.1-125# FF
Pump body
Cast iron ASTM A48 CL35
Impeller
Cast iron ASTM A48 CL35
Shaft
AISI 431 stainless steel
Casing ring
420 SS
O-ring/elastomer
Buna
Material
Flange
Description
Density
Viscosity
Maximum operating pressure
Seal
Clean Water
Construction

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6. INSTALLATION
6.1 INSTALLATION POINT
(1) Install the equipment in an easily accessible place in order to carry out overhauls and maintenance.
(2) Prohibit access to unauthorized persons by using related closure points.
(3) Place the equipment as close as possible to the water supply, making sure that the di󰀨erence in
height between the water surface and the pump shaft is minimal and that the length of the suction
pipe is as short as possible.
(4) The sum between the suction pressure and the gauge pressure of the pump must always be
less than the minimum permissible pressure (see section 4 - Specications).
6.2 LIFTING
In order to move the electric pump or the individual pump you must lift the load by means of straps, creating
an angle of less than 60 degrees, as shown in the gure:
6.3 CEMENTED BASE
One should note that electric pump units must be xed in a stable and durable manner to a solid cemented
base so that the axes of the pumps and the motors always remain correctly and securely aligned. The
cement base must be su󰀩ciently rigid, permanent and aligned, as well as being located on ground capable
of bearing a permitted load of adequate support facilities. The top part of the unit must rest completely
on the cemented base; once the top part has been secured, the alignment of the coupling needs to be
checked again.
If you need to limit, as much as possible, the vibrations of the equipment by using elastic dampers, the
latter should not be placed directly under the metal proles, but instead, you will need to produce a solid
plate with a weight of one and a half times or two times the overall weight of the unit, arranging the dampers
under the assembly that combines the top part with the plate. There are several valid methods although
this plate is typically made with concrete and its dimensions exceed those of the top by about 1.875” (0.2
meters) on all four sides.
Ensure that there are no personnel exposed to
danger during the operation. To lift the assembly,
do not use the attachment points of the motor or the
pump because they may not have been designed
to bear the combined weight of the pump, motor
and base.

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Generally, an incorrect cement base is the cause of premature failure and this invalidates the warranty
period.
6.4 PIPES
The installation must be done according to the arrangement shown in the Figure:
1. Make sure that the suction and delivery ducts do not transmit any stresses to the pump, by installing
su󰀩ciently strong supports. If this is not done, the pump could become misaligned and even break.
2. Fit any check valves (between the pump and the delivery valve) in the following cases:
- In very long pipes.
- If the head is high.
- If the operation is automatic.
- When you ll a tank under pressure.
- When the operation is in parallel.
3. Mount air relief valves, if required, in those parts of the installation where it is impossible to avoid the
formation of air bubbles. However, they must not be tted at points where the pressure is less than
atmospheric pressure since the valve would suck in air rather than expel it.
4. To reduce the e󰀨ect of a water hammer, mount a check valve with spring.
1 Pump
2Motor
3Mount
4Elastic sleeve
5Check valve
6Shut-off valve
7Bottom valve
8Eccentric reduction

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5. Suction systems:
- The bottom end of the suction pipe must remain submerged and at a depth of at least twice the
diameter of the pipe (2D) and at a distance from the bottom of 1 time to 1 and a half times the diameter
(1~1.5 D).
- Fit a bottom valve with a lter at the beginning of the suction pipe to prevent the entry of any foreign
bodies.
-The suction pipe will be installed with an upward gradient towards the pump (of more than 1%) to avoid
the formation of air bubbles. The pipes and other accessories must be connected in such a way so as
not to create any air intake between the di󰀨erent elements.
- Make sure that the suction pipe is as short and straight as possible and try to avoid any unnecessary
curves or additional length. Do not install any shut-o󰀨 valve in this section.
- Unless the installation project indicates something di󰀨erent, use the dimensions for the suction pipe
and eccentric reduction recommended in this Table. The eccentric reduction will be installed with an
upward gradient towards the pump to avoid the formation of air bubbles.
6. In systems where a booster pump is present:
- The installation of a shut-o󰀨 valve is recommended in the suction pipe to facilitate dismantling and
overhauls.
- Install the suction pipe with an upward gradient towards the pump to avoid the formation of air bubbles.
Pipe Size Reduction Pipe Size Reduction
50 x 32 65 65 x 50 80 80 x 50
2” X 1.25” 2.5” 2.5” x 2” 3” 3” x 2”
65 x 40 80 80 x 65 100 100 x 65
2.5” x 1.5” 3” 3” x 2.5” 4” 4” x 2.5”
65 x 50 100 100 x 65 125 125 x 65
2.5” x 2” 4” 4” x 2.5” 5” 5” x 2.5”
80 x 65 125 125 x 80 150 150 x 80
3” x 2.5” 5” 5” x 3” 6” 6” x 3”
100 x 80 150 150 x 100 200 200 x 100
4” x 3” 6” 6” x 4” 8” 8” x 4”
125 x 100 200 200 x 125 250 250 x 125
5” x 4” 8” 8” x 5” 10” 10” x 5”
150 x 125 250 250 x 150 300 300 x 150
6” x 5” 10” 10” x 6” 12” 12” x 6”
Suction x
Discharge
2 Pole 4 Pole

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6.5 ALIGNMENT
Pumps supplied with motors are connected to these through a simple elastic coupling or with a spacer.
The pumps come on the market after being aligned within the production center; nevertheless, during
installation, the top of the coupling assembly usually becomes misaligned due to anchoring with anchor
pins. Therefore, the coupling needs to be adjusted by using shims underneath and aligning the pump while
staying within the tolerances shown in the gure below.
External diameter CA, B A-B inch mm Min Max
1.85 < 0.063 0.03 - 0.13 < 0.03 WE2 1.85 0.063 1.6 0.030 0.130 0.030
2.32 < 0.063 0.04 - 0.16 < 0.04 WE3 2.32 0.063 1.6 0.040 0.160 0.040
2.6 < 0.063 0.05 - 0.18 < 0.05 WE4 2.6 0.063 1.6 0.050 0.180 0.050
3.13 < 0.063 0.06 - 0.22 < 0.06 WE5 3.13 0.063 1.6 0.060 0.220 0.060
3.65 < 0.063 0.06 - 0.22 < 0.06 WE10 3.65 0.063 1.6 0.060 0.220 0.060
4.48 < 0.094 0.08 - 0.23 < 0.08 WE20 4.48 0.094 2.4 0.080 0.230 0.080
5.42 < 0.094 0.1 - 0.28 < 0.1 WE30 5.42 0.094 2.4 0.100 0.280 0.100
6.63 < 0.094 0.12 - 0.35 < 0.12 WE40 6.63 0.094 2.4 0.120 0.350 0.120
8.13 < 0.094 0.14 - 0.43 < 0.14 WE50 8.13 0.094 2.4 0.140 0.430 0.140
C
Dimension [mm]
A, B [inch]
A-B
[inch]
size B dimension
External diameter CA, B A-B inch mm Min Max
1.85 < 0.063 0.03 - 0.13 < 0.03 WE2 1.85 0.063 1.6 0.030 0.130 0.030
2.32 < 0.063 0.04 - 0.16 < 0.04 WE3 2.32 0.063 1.6 0.040 0.160 0.040
2.6 < 0.063 0.05 - 0.18 < 0.05 WE4 2.6 0.063 1.6 0.050 0.180 0.050
3.13 < 0.063 0.06 - 0.22 < 0.06 WE5 3.13 0.063 1.6 0.060 0.220 0.060
3.65 < 0.063 0.06 - 0.22 < 0.06 WE10 3.65 0.063 1.6 0.060 0.220 0.060
4.48 < 0.094 0.08 - 0.23 < 0.08 WE20 4.48 0.094 2.4 0.080 0.230 0.080
5.42 < 0.094 0.1 - 0.28 < 0.1 WE30 5.42 0.094 2.4 0.100 0.280 0.100
6.63 < 0.094 0.12 - 0.35 < 0.12 WE40 6.63 0.094 2.4 0.120 0.350 0.120
8.13 < 0.094 0.14 - 0.43 < 0.14 WE50 8.13 0.094 2.4 0.140 0.430 0.140
C
Dimension [mm]
A, B [inch]
A-B
[inch]
size B dimension

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If the pump was purchased without a motor, but the intention is to connect one during installation, you will
need to correct the shift of the coupling by inserting a plate under the feet of the motor, by adjusting the
disparity according to the range shown in the Figure.
The alignment operation is achieved by removing the coupling guard, although this will need to be retted
carefully before starting up the pump.
The size of the coupling depends on the power and speed of the motor connected to the pump. For further
information contact EBARA.
6.6 ELECTRICAL SYSTEM
Checkthat the motor is cooled properly, by leaving the air inletsandoutlets unobstructed. Our recommendation
is to install the equipment in a ventilated place away from any heat source.
The condensate drainage outlets must be located in the lower part of the motor. The drainage caps can
only be removed when the motor is protected from the water.
6.6.1 ELECTRICAL CONNECTION
All electrical connections of the equipment must be carried out by qualied personnel with the power supply
switched o󰀨.
- Use power supply cables that are adequately sized to carry the maximum current absorbed by the
motor, in addition to the margin set by local requirements; this will avoid any overheating and/or voltage
drops (voltage drops must be less than 5% during the start-up phase).
- Make sure the cables reach the terminal box with a curve that prevents water from getting in and
running over them.
- The contact surfaces of the connections must be clean and protected against rust. Do not place any
washers or nuts between the terminals on the motor and those providing access to the mains.
- Check the airtight sealing of the cable gland to ensure the degree of protection indicated on the
nameplate.
- Avoid any mechanical stress being transferred to the motor terminals.
- Comply with the current and frequency limits indicated on the nameplate of the motor.
- A switch must be installed to prevent any accidents involving electrical discharges, and overload
protection against power surges for motors with the aim of avoiding any damage due to overheating.

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6.6.2 ELECTRICAL MAINTENANCE
Any work on the motor must be carried out with the appliance switched o󰀨 and after disconnecting the
mains power supply.
- Check on a regular basis that the requirements regarding installation and electrical connections are
complied with.
- It is recommended that bearings are replaced after three years.
7. OPERATION
7.1 BEFORE STARTING THE PUMP
1. Make sure that the pipes are ushed after the installation is completed, since any impurities may lead
to faults, noise and excess wear around the mechanical closure and the other parts of the pump.
2. Check that the pump turns easily by spinning the shaft with your hand. If the movement is sti󰀨 or
irregular, check the pump because the mechanical closure may be damaged, the gasket too tight or
there might even be rust inside the pump.
3. Check the operating details of the motor, which are listed on the nameplate.
4. Do not operate the pump before priming it rst. If the system is in suction mode, the pump and the
suction pipe must be lled with water via the relevant device duly installed on the delivery pipe. If the
suction is primed, the pump must be lled with water by opening the suction and delivery valves. Make
sure that no air remains inside the pump, to do this, you need to rotate the shaft by hand.
5. Check the direction of rotation of the motor, as shown below:
- Close the delivery and suction valves.
- Switch on the motor for 1 or 2 seconds, then stop it.
- Visually check that the direction of rotation is correct via the connection or the fan on the
motor. The direction of rotation is indicated by an arrow on the pump body. Generally, it is
clockwise (to the right) when the observer is facing the fan on the motor.
- After removing the coupling guard, put it back immediately after checking the rotation.

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7.2 STARTING THE PUMP
1. Shut o󰀨 the main delivery valve. Open the suction valve if it is closed.
2. Turn on and o󰀨 the switch to start the motor once or twice, to ensure that there are no faults in the
startup.
3. When the rotation speed remains stable at the nominal speed, gradually open the delivery valve.
4. Check that there are no signicant variations in the pump pressure and in the current absorbed by the
motor. Check that there are no signicant vibrations and/or unusual noises.
5. Follow the same procedure during subsequent startups if the operating conditions are normal, observing
the instructions in Chapter 8. Maintenance.
7.3 STOPPING THE PUMP
Before stopping the pump, you are advised to close the delivery valve gradually.
If the pump stops due to a sudden lack in the power supply, disconnect the motor switch. This will avoid the
pump starting up again as soon as the power supply returns, thereby endangering sta󰀨.
8. MAINTENANCE
Maintenance operations must be performed by qualied personnel: an error may lead to damage caused
by electrical discharge, re or malfunctions that in turn could lead to an accident.
Make sure that the operating power switch is disconnected during maintenance; the pump could start up
suddenly if it is in automatic mode.
If the liquid being pumped is hot water, keep at a safe distance until it has cooled down. Similarly, do not
touch the surface of the motor without making sure that the temperature has dropped to a tolerable level.
8.1 DAILY INSPECTION
1. Signicant variations in pressure, capacity, electricity, vibrations or noise may be a sign of a malfunction
of the pump. Refer to section 8.5 “Troubleshooting”. It is advisable to keep a daily register on the
operating conditions to allow discovering any symptoms that may be the result of a potential failure.
2. The maximum temperature for the bearing is 104°F above the ambient temperature, with a maximum
total limit of 176°F
3. Generally, the mechanical seal does not show any leaks. Sometimes, at the beginning of operation
there is a small leak of water which then gradually decreases. If, during normal operation, there is a
major leak of water, you need to replace the seal.

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8.2 PRECAUTIONS DURING OPERATION
1. Operating the pump for a long period of time with the delivery valve closed may cause damage to some
of the pump components due to overheating inside the pump.
2. Too many stops and starts can cause damage to the pump. Limiting the number of starts is recommended
in line with the following:
N ≤ 6 when P ≤ 10 hp
N ≤ 4 when 15 hp ≤ P ≤ 30 hp
N ≤ 3 when P>30 hp
N = startup/h
P = motor power
8.3 PRECAUTIONS DURING STORAGE
1. The pump body may fracture if the water inside freezes; insulate the pump or remove all the water from
the inside.
2. If you have any spare pumps, you must perform test runs on them on a regular basis and keep them
ready for use at all times.
3. When a pump remains o󰀨 for a long period of time, you must take great care to prevent any oxidation
on the surface of the bearing, shaft, coupling, etc.
8.4 REPLACING PARTS
Replace worn parts according to the following table:
This replacement period is an average and refers to normal operating conditions.
Part Condition Replacement period
Mechanical seal Water leakage Yearly
Ball bearings Excessive noise or vibration Every 2 or 3 years
Pump body O-ring After every dismantling ---
Coupling rubber parts As soon as any signs of
damage appear Yearly

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8.5 TROUBLESHOOTING
Although the equipment usually functions according to the user’s requirements, in some cases its operation
may not come up to expectations due to problems with the system or the power supply. The following table
may be useful in nding possible solutions in the event of failures or malfunctions:
PUMP
Fault Causes Measures to be taken
- The control panel is not working
correctly.
-
Check all conditions.
-
Motor failure. -
Repair the motor.
-
Faults in the power supply. -
Check and repair.
-
Rotate it by hand. Reassemble.
-
Friction on rotation shaft. -
Repair in specialist workshop.
-
Pump clogged. -
Remove foreign bodies.
-
Foreign bodies in the bottom
valve.
-
Remove foreign bodies.
-
Malfunction in the bottom valve. -Replace the valve.
-
Water leakage from the suction
pipe.
-
Check the suction pipe.
- Air entering the suction pipe or
seal.
- Check the suction pipe and
mechanical seal.
-
The pump does not turn. -
Check that the impeller is free.
-
The delivery valve is closed or
half-closed.
-
Open the valve.
-
The suction head is too low for
the pump.
-
Check the project.
-
The direction of rotation is not
correct.
-
Correct the electrical
connections.
-
Low rotation speed.
-
Measure the RPM with a
tachometer.
-
Low voltage. -
Check the power supply.
-
Blocking in the bottom valve or in
the filter.
-
Remove foreign bodies.
-
Impeller is blocked. -
Remove foreign bodies.
-
Pipe clogged. -
Remove foreign bodies.
-
Air entering the system.
-
Check and repair the suction
pipe and shaft seal.
The motor will not start.
Low flow rate
There is no priming.
The pump has no flow rate

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Fault Causes Measures to be taken
-
Leakage in the delivery pipe. -
Check and repair.
-
Impeller worn. -
Check the impeller.
-
Significant head losses in the
system.
-
Review the project.
-
Liquid temperature very high. The
liquid is volatile.
-
Review the project.
-
Cavitation. -
Seek expert advice.
-
The pump has not been primed. -
Prime the pump correctly.
-
Air entering the system.
-
Check and repair the suction
pipe and shaft seal.
-
Air bubbles in the suction pipes. -
Vent the pipes.
-
The suction head is too high for
the pump.
-
Review the project.
-
The voltage is low or the
imbalance between the phases is
high.
-
Check the power supply.
-
The flow rate is too high or the
head is too low.
-
Partially shut off the delivery valve.
-
Foreign bodies inside the pump. -
Remove foreign bodies.
-
The mechanical seal was not
fitted correctly.
-
Fit it correctly.
-
Bearings damaged. -
Replace the bearings.
-
Friction in the rotation areas. The
shaft is bent.
-
Repair in specialist workshop.
-
The direction of rotation is not
correct.
-
Check and correct the
connection.
-
The density and/or viscosity level
of the liquid is high.
-
Review the project.
-
Bearings damaged. -
Replace the bearings.
-
In operation for a long time with
the valve closed or half-closed.
-
Avoid such a situation; close the
valve or stop the pump.
The bearings are
overheating.
Power surge
Water comes out initially
and then stops abruptly.
Low flow rate continued

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End Suction Centrifugal GS Series
MOTOR
Fault Causes Measures to be taken
-
Fault in installation. -
Check installation.
-
Bearings damaged. -
Replace the bearings.
-
Flow rate too high.
-
Reduce the aperture of the
delivery valve.
-
Flow rate too low.
-
Increase the aperture of the
delivery valve.
-
Impeller is blocked. -
Remove foreign bodies.
-
The direction of rotation is not
correct.
-
Check and correct the
connection.
-
Friction in the rotation areas. The
shaft is bent.
-
Repair in specialist workshop.
-
Cavitation. -
Seek expert advice.
-
Vibrations in the piping.
-
Reinforce the piping or fit an
inverter
-
Defective fitting of the mechanical
seal.
-
Fit it correctly.
-
The mechanical seal is damaged. -
Replace the mechanical seal.
-
Overpressure in delivery. -
Review the project.
-
The shaft is bent. -
Repair in specialist workshop.
Excessive water leakage
from the shaft seal.
Excessive operating
vibration and noise.
Fault Causes Measures to be taken
-
The winding is broken or has
been cut.
-
Repair in specialist workshop.
-
Stator short-circuited. -
Repair in specialist workshop.
-
Grounded. -
Repair in specialist workshop.
-
The bearings are blocked. -
Repair the bearings.
-
The voltage is low. -
Change the nominal voltage.
-
Loss of phases in the power
supply.
-
Check the power supply.
Motor does not start

18
EBARA PUMPS AMERICAS CORPORATION
www.pumpsebara.com
(t) 803.327.5005 (f) 803.327.5097 rev. 03/22
End Suction Centrifugal GS Series
Fault
Causes Measures to be taken
-
Operation without a phase. -
Check the power supply.
-
Power surges. -
Correct the power surges.
-
Friction between the rotor and
stator.
-
Align and/or replace the bearing.
-
Obstructions in the cooling fan. -
Remove foreign bodies.
-
Fault in installing the motor. -
Connect the pump correctly.
-
Poor Star/Delta commutation. -
Correct the cabling.
-
High power surges. -
Correct the power surges.
-
Fan is blocked. -
Release the fan.
-
Wrong voltage.
-
Change the motor for one with
the appropriate voltage.
-
The bearings are blocked. -
Repair the bearings.
-
Stator short-circuited. -
Repair in specialist workshop.
-
Stator grounded. -
Repair in specialist workshop.
-
Low voltage. -
Change the nominal voltage.
-
Poor Star/Delta commutation. -
Correct the cabling.
-
Overloading. -
Reduce the current.
-
Defective electrical connection.
-
Correct the electrical
connections.
Abnormal noise or
excessive vibrations.
Low rotation speed.
Motor overheating.
Appearance of smoke
and/or bad smell.

19
EBARA PUMPS AMERICAS CORPORATION
www.pumpsebara.com
(t) 803.327.5005 (f) 803.327.5097 rev. 03/22
End Suction Centrifugal GS Series
8.6 RESIDUAL RISKS
The use and maintenance of the following pieces of equipment may lead to risks beyond the capacity of the
manufacturer and, therefore, the user must pay the utmost attention to maintenance work and the handling
of the equipment. The following risks need to be considered:
Operation Risk Measures to be taken
-
Burns
-
Wait until the temperature goes
down
-
Check the temperature before
touching
-
Damage caused due to it being
empty or due to pressure
-
Stop the pump and proceed very
carefully
-
Damage caused by entrapment
-
Stop the pump and proceed very
carefully
-
Always fit protection guards
-
Keep your distance from rotating
parts
Transport and lifting - Impacts and falls - Proceed with care
Maintenance

20
EBARA PUMPS AMERICAS CORPORATION
www.pumpsebara.com
(t) 803.327.5005 (f) 803.327.5097 rev. 03/22
End Suction Centrifugal GS Series
GSU Standard Construction Parts Reference
9. CONSTRUCTION
Num. Name Quant.
1Casing 1
10 Pump Guard 2
11
Casing Cover 1
21 Impeller 1
31
Shaft 1
039-1 Key 1
039-2 Key 1
048-1 Impeller Nut 1
048-2
Impeller Nut 1
51 Bearing Housing 1
845
Bearing Cover 1
849 Ball Bearing 2
13
Deflector 2
696 Support Foot 1
107 Casing Wear Ring 1
Num. Name Quant.
25 Impeller Wear Ring 1
111
Mechanical seal 1
115 Casing O-ring 1
120-1
Casing Bolt 6
120-2 Nut and Washer 6
120-3
Bolt 1
120-4
Bolt 4
120-5 Bolt 1
120-6
Washer 4
137 Impeller washer 1
137-2
Lock Washer 1
234 Spacer Ring 1
193
Plug 1
217 Drain Plug 1
50
Spring Pin 2
Num. Name Quant.
1
Casing 1
10 Pump Guard 2
11
Casing Cover 1
21 Impeller 1
31
Shaft 1
039-1 Key 1
039-2
Key 1
048-1 Impeller Nut 1
048-2
Impeller Nut 1
51 Bearing Housing 1
845
Bearing Cover 1
849 Ball Bearing 2
13
Deflector 2
696 Support Foot 1
107
Casing Wear Ring 1
Num. Name Quant.
25 Impeller Wear Ring 1
111
Mechanical seal 1
115 Casing O-ring 1
120-1 Casing Bolt 6
120-2 Nut and Washer 6
120-3
Bolt 1
120-4 Bolt 4
120-5 Bolt 1
120-6
Washer 4
137 Impeller washer 1
137-2
Lock Washer 1
234 Spacer Ring 1
193 Plug 1
217 Drain Plug 1
50
Spring Pin 2
1
A A
B B
4
4
3
3
2
21
39-1
193
120-6
107
21
137-2
1
137-1
48-2
111
25
234
120-2
13
120-1
51
845
120-2
120-1
696
115
120-7
120-4
31
48-1
217
39-2
120-3
13
120-5
849
11
10
849
REVISIONS
NO. DESCRIPTION DATE APPROVED BY
A