GORMAN-RUPP S8A1-E95 460/3 Application guide

OM-06258-02
February 18, 2020
GORMAN‐RUPP PUMPS
www.grpumps.com
2020 Gorman‐Rupp Pumps Printed in U.S.A.
INSTALLATION, OPERATION,
AND MAINTENANCE MANUAL
WITH PARTS LIST
SUBMERSIBLE PUMPS
MODELS
S8A1-E95 460/3
and
S8A1-E95 575/3

Register your new
Gorman‐Rupp pump online at
www.grpumps.com
Valid serial number and e‐mail address required.
RECORD YOUR PUMP MODEL AND SERIAL NUMBER
Please record your pump model and serial number in the
spaces provided below. Your Gorman‐Rupp distributor
needs this information when you require parts or service.
Pump Model:
Serial Number:

TABLE OF CONTENTS
i
INTRODUCTION PAGE I - 1.................................................
SAFETY ‐ SECTION A PAGE A - 1............................................
INSTALLATION - SECTION B PAGE B - 1....................................
GENERAL INFORMATION PAGE B - 1..................................................
PUMP SEAL PAGE B - 1..............................................................
LUBRICATION PAGE B - 1.............................................................
PUMP INSTALLATION PAGE B - 1......................................................
Pump Motor Specifications PAGE B - 2..............................................
Pump Dimensions PAGE B - 2.....................................................
Lifting PAGE B - 2.................................................................
Piping PAGE B - 3................................................................
ELECTRICAL CONNECTIONS PAGE B - 4...............................................
Field Wiring Connections (Incoming Power) PAGE B - 4...............................
Grounding Methods PAGE B - 5....................................................
Pump Power Cable Connections PAGE B - 6.........................................
Control Box Specifications PAGE B - 7..............................................
Control Box Connections PAGE B - 7...............................................
Liquid Level Devices PAGE B - 7....................................................
WIRING DIAGRAMS PAGE B - 8.......................................................
OPERATION - SECTION C PAGE C - 1......................................
GENERAL INFORMATION PAGE C - 1..................................................
Pump Performance PAGE C - 1.....................................................
Control Box PAGE C - 1...........................................................
PUMP OPERATION PAGE C - 1........................................................
Liquid Temperature And Overheating PAGE C - 1.....................................
Impeller Rotation PAGE C - 2.......................................................
STARTING, STOPPING AND OPERATIONAL CHECKS PAGE C - 3.........................
Starting PAGE C - 3...............................................................
Stopping PAGE C - 3..............................................................
Operational Checks PAGE C - 3....................................................
COLD WEATHER PRESERVATION PAGE C - 4...........................................
LUBRICATION PAGE C - 4.............................................................
Draining Oil PAGE C - 5...........................................................
Condition of Oil Oil PAGE C - 5.....................................................
Adding Oil PAGE C - 5............................................................
TROUBLESHOOTING - SECTION D PAGE D - 1..............................
PREVENTIVE MAINTENANCE PAGE D - 3...............................................
PUMP MAINTENANCE AND REPAIR ‐ SECTION E PAGE E - 1.................
STANDARD PERFORMANCE CURVE PAGE E - 1........................................
PARTS LISTS:
Pump Assemblies PAGE E - 3......................................................
460V Terminal Housing and Cable Assemblies PAGE E - 5.............................

TABLE OF CONTENTS
(continued)
ii
575V Terminal Housing and Cable Assemblies PAGE E - 6.............................
PUMP AND SEAL DISASSEMBLY AND REASSEMBLY PAGE E - 7.........................
PUMP END DISASSEMBLY PAGE E - 8.................................................
Strainer Removal PAGE E - 8.......................................................
Draining Oil From Seal Cavity PAGE E - 8............................................
Draining Oil From Motor Cavity PAGE E - 8..........................................
Positioning Pump For Disassembly PAGE E - 8.......................................
Strainer Plate and Suction Head Removal PAGE E - 9.................................
Impeller Removal PAGE E - 9......................................................
Lower Seal Removal PAGE E - 9....................................................
Upper Seal Removal PAGE E - 9...................................................
PUMP END REASSEMBLY PAGE E - 10..................................................
Cleaning and Inspection of Pump Parts PAGE E - 10...................................
Upper Seal Installation PAGE E - 11..................................................
Lower Seal Installation PAGE E - 12..................................................
Impeller Installation PAGE E - 13.....................................................
Suction Head and Strainer Plate Installation PAGE E - 13...............................
Strainer Screen and Base Plate Installation PAGE E - 13................................
MOTOR DISASSEMBLY PAGE E - 14....................................................
Terminal Housing and Power Cable Removal and Disassembly PAGE E - 14..............
Intermediate and Motor Housing Disassembly PAGE E - 15.............................
Rotor and Bearing Removal PAGE E - 15.............................................
Stator Removal PAGE E - 16........................................................
Relief Valve PAGE E - 16............................................................
Hoisting Bail PAGE E - 17...........................................................
MOTOR REASSEMBLY PAGE E - 17.....................................................
Stator Installation PAGE E - 17......................................................
Bearing Installation PAGE E - 18.....................................................
Rotor and Intermediate Reassembly PAGE E - 19......................................
Rotor and Intermediate Installation PAGE E - 20.......................................
Terminal Housing and Power Cable Reassembly and Installation PAGE E - 20.............
Sealing Terminal Housing Connections With Silicone Adhesive PAGE E - 21..............
Sealing Terminal Housing Connections With Potting Compound PAGE E - 22.............
Terminal Housing Installation PAGE E - 23............................................
FINAL ASSEMBLY PAGE E - 23.........................................................
VACUUM TESTING PAGE E - 24........................................................
LUBRICATION PAGE E - 24.............................................................
Seal Cavity PAGE E - 24............................................................
Motor Housing Cavity PAGE E - 25...................................................

S SERIES PUMPS OM-06258
PAGE I - 1INTRODUCTION
INTRODUCTION
Thank You for purchasing a Gorman‐Rupp 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 in
structions and precautions for every aspect of
each specific application. Therefore, it is the re
sponsibility 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 com
promised by the installation. Pumps and related
equipment must be installed and operated ac
cording to all national, local and industry stan
dards.
If there are any questions regarding the pump or
its application which are not covered in this man
ual or in other literature accompanying this unit,
please contact your Gorman‐Rupp distributor, or
The Gorman‐Rupp Company:
The Gorman‐Rupp Company
P.O. Box 1217
Mansfield, Ohio 44901-1217
Phone: [phone]
or:
Gorman‐Rupp of Canada Limited
70 Burwell Road
St. Thomas, Ontario N5P 3R7
Phone: [phone]
For information or technical assistance on the
power source, contact the power source manufac
turer's local dealer or representative.
HAZARD AND INSTRUCTION
DEFINITIONS
The following are used to alert maintenance per
sonnel to procedures which require special atten
tion, to those which could damage equipment, and
to those which could be dangerous to personnel:
Immediate hazards which WILL result in
severe personal injury or death. These
instructions describe the procedure re
quired and the injury which will result
from failure to follow the procedure.
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.
Hazards or unsafe practices which COULD
result in minor personal injury or product
or property damage. These instructions
describe the requirements and the possi
ble damage which could result from failure
to follow the procedure.
NOTE
Instructions to aid in installation, operation, and
maintenance or which clarify a procedure.

OM-06258 S SERIES PUMPS
PAGE A - 1SAFETY
SAFETY - SECTION A
This information applies to the S Series
submersible motor driven pumps indi
cated on the front cover of this manual.
Because pump installations are seldom
identical, this manual cannot possibly
provide detailed instructions and pre
cautions for each specific application.
Therefore, it is the owner/installer's re
sponsibility to ensure that applications
not addressed in this manual are per
formed only after establishing that nei
ther operator safety nor pump integrity
are compromised by the installation.
Before attempting to open or service the
pump:
1. Familiarize yourself with this man
ual.
2. Lock out incoming power to the
control box to ensure that the
pump will remain inoperative.
3. Allow the pump to completely cool
if overheated.
4. Close the discharge valve (if
used).
This pump is not designed to pump vol
atile, explosive, or flammable materials.
Do not attempt to pump any liquids for
which you pump is not approved, or
which may damage the pump or endan
ger personnel as a result of pump fail
ure. Consult the factory for specific ap
plication data.
Before connecting any cable to the con
trol box, be sure to ground the control
box. Refer to the Control Box Manual for
the suggested grounding methods.
The pump motor is designed to be oper
ated through the control box furnished
with the pump. The control box provides
overload protection and power control.
Do not connect the pump motor directly
to the incoming power lines.
The electrical power used to operate
this pump is high enough to cause inju
ry or death. Obtain the services of a
qualified electrician to make all electri
cal connections. Make certain that the
pump and enclosure are properly
grounded; never use gas pipe as an
electrical ground. Be sure that the in
coming power matches the voltage and
phase of the pump and control before
connecting the power source. Do not
run the pump if the voltage is not within
the limits. If the overload unit is tripped
during pump operation, correct the
problem before restarting the pump.
The electrical power used to operate
this pump is high enough to cause inju
ry or death. Make certain that the control
handle on the control box is in the OFF

S SERIES PUMPS OM-06258
PAGE A-2 SAFETY
position and locked out, or that the pow
er supply to the control box has been
otherwise cut off and locked out, before
attempting to open or service the pump
assembly. Tag electrical circuits to pre
vent accidental start‐up.
Never attempt to alter the length or re
pair any power cable with a splice. The
pump motor and cable must be com
pletely waterproof. Injury or death may
result from alterations.
All electrical connections must be in ac
cordance with The National Electric
Code and all local codes. If there is a
conflict between the instructions pro
vided and N.E.C. Specifications, N.E.C.
Specifications shall take precedence.
All electrical equipment supplied with
this pump was in conformance with
N.E.C. requirements in effect on the
date of manufacture. Failure to follow
applicable specifications, or substitu
tion of electrical parts not supplied or
approved by the manufacturer, can re
sult in severe injury or death and void
warranty.
After the pump has been installed, make
certain that the pump and all piping or
hose connections are secure before op
eration.
Obtain the services of a qualified elec
trician to troubleshoot, test and/or ser
vice the electrical components of this
pump.
Approach the pump cautiously after it
has been running. Although the motor is
cooled by the liquid being pumped, nor
mal operating temperatures can be high
enough to cause burns. The tempera
ture will be especially high if operated
against a closed discharge valve. Never
operate against a closed discharge
valve for long periods of time.
Do not remove plates, covers, gauges,
pipe plugs, or fittings from an over
heated pump. Vapor pressure within the
pump can cause parts being disen
gaged to be ejected with great force. Al
low the pump to completely cool before
servicing.
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 suffi
cient capacity and that they are posi
tioned so that loads will be balanced
and the pump or components will not be
damaged when lifting. Suction and dis
charge hoses and piping must be re

OM-06258 S SERIES PUMPS
PAGE A - 3SAFETY
moved from the pump before lifting. Lift
the pump or component only as high as
necessary and keep personnel away
from suspended objects. Pumps and related equipment must be
installed and operated according to all na
tional, local and industry standards.

S SERIES PUMPS OM-06258
PAGE B - 1INSTALLATION
INSTALLATION - SECTION B
GENERAL INFORMATION
Review all SAFETY information in Section A.
Since pump installations are seldom identical, this
section is intended only to summarize general rec
ommendations and practices required to inspect,
position, and arrange the pump and piping. If there
are any questions concerning your specific instal
lation, contact your Gorman‐Rupp distributor or
the Gorman‐Rupp Company.
Liquid level devices are available from Gorman‐
Rupp as optional equipment. For information on
installing and operating these items, refer to the lit
erature accompanying them.
Pump Model Designation
Following is a description of the model numbering
system for S Series pumps. These submersible
pumps are available in a range of sizes. Refer to the
following chart to identify the size of your specific
pump model.
S
Series
Discharge Size
Pump Hydraulics
Pump Construction
H.P.
Voltage/Phase
3 C 1 E 230/3- 6.2
Pump Model
PREINSTALLATION INSPECTION
The pump assembly was inspected and tested be
fore shipment from the factory. Before installation,
check for damage which may have occurred dur
ing shipment. Check as follows:
a. Inspect the pump assembly for cracks, dents,
damaged threads, and other obvious dam
age.
b. Check for loose attaching hardware. Since
gaskets tend to shrink after drying, check for
loose hardware at the mating surfaces.
c. Inspect the power cable for cuts or any other
obvious damage.
d. Check that amperes, phase, voltage and
hertz indicated on the name plate match the
ratings on the control box and incoming pow
er.
e. Carefully read all tags, decals, and markings
on the pump, and perform all duties indicated.
f. Check for oil leaks. If there is any indication of
an oil leak, see LUBRICATION at the end of
this manual.
PUMP SEAL
There are two shaft seals in the pump. The lower
seal prevents liquid from entering the intermediate
cavity at the impeller end. The upper seal prevents
oil leakage from the motor housing cavity and acts
as back‐up protection in the event of lower seal fail
ure.
LUBRICATION
These pumps utilize two lubrication cavities. The
motor housing cavity provides lubrication to the
motor assembly and bearings, while the intermedi
ate cavity provides lubrication to the pump seal.
The pumps are fully lubricated when shipped from
the factory. However, lubrication levels must be
checked before installing the pump (see LU
BRICATION in MAINTENANCE AND REPAIR -
SECTION E). An additional quart (0,9 liter) of oil is
provided to “top off” the oil level in the pump motor
cavity. If the oil level is abnormally low, determine
the cause before putting the pump into service.
Due to differences in pump design, the quantity of
oil and manner in which oil is to be added to the
seal cavity varies between pump models. Refer to
Table B‐2 for oil capacities and positions for filling
the seal cavity in each pump. Motor cavities requir
ing lubrication should always be positioned verti
cally for filling. Refer to LUBRICATION, Section C
for lubrication specifications and intervals.
PUMP INSTALLATION
When installing or servicing the pump
or controls, follow all requirements for
the installation of wiring or electrical

OM-06258 S SERIES PUMPS
PAGE B - 2 INSTALLATION
equipment as outlined in the National
Electric Code. Follow all safety require
ments. Failure to observe these require
ments could result in injury or death to
personnel.
Do not allow the free end of the power
cable to enter the liquid being pumped.
The free end of the cable must be kept dry
to prevent liquid from wicking through the
cable and into the motor.
NOTE
Refer to the performance curve in Maintenance
and Repair - Section E when determining the
most efficient piping installation. The recom
mended maximum submergence depth is 65
feet.
Pump Motor Specifications
See Table B‐1 for pump specifications.
Table B‐1. Pump Specifications
Dual
Voltage
Locked
Rotor
Amperes
Pump
HP/
KW
Motor
Speed
(RPM)
Full
Load
Amperes
No
Load
Amperes
Discharge
Size
(NPT)
Model Voltage/
Phase
S8A
460/3
575/3 NO 8 INCH95 HP 1750
128
102
40.3
30.9
715
556
Table B‐2. Additional Specifications
Pump
Model
Voltage/
Phase
460/3
575/3
S8A
Approximate
Weight - Lbs. (kg) Oil Capacity
Ounces (Liters)
Seal Cavity
Filling
Position
(H)orizontal
(V)ertical
Pump 50 Ft. Cable Seal
Cavity
Motor
Cavity
870 (395) 105 (48) 176 (5,2) 576 (17) V
150 (68)
Pump Dimensions
For the approximate physical dimensions of your
pump, refer to the pump specification data sheet
or contact your Gorman‐Rupp distributor or the
Gorman‐Rupp Company.
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.
Refer to Table B-2 for the approximate maximum
weight for your pump.
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 suffi
cient capacity and that they are posi
tioned so that loads will be balanced
and the pump or components will not be
damaged when lifting. Suction and dis

S SERIES PUMPS OM-06258
PAGE B - 3INSTALLATION
charge hoses and piping must be re
moved from the pump before lifting. Lift
the pump or component only as high as
necessary and keep personnel away
from suspended objects.
Positioning the Pump
NOTE
Before installing and operating the pump, check
the direction of impeller rotation to ensure that the
pump is properly wired at the control box. See IM
PELLER ROTATION, Section C.
The pump is designed to operate fully or partially
submerged. The rotating parts are oil lubricated,
and the motor is cooled by a constant flow of liquid
or air discharged through internal passages.
As a safeguard against rupture or explosion due to
heat, models equipped with oil‐lubricated motors
are fitted with a pressure relief valve which will open
if vapor pressure within the pump motor reaches a
critical point.
The pump will operate if positioned on its side, but
this is not recommended because the motor
torque could cause the pump to roll during opera
tion.
The pump should be independently secured and
supported by the lifting device fitted on the pump.
If the application involves a lot of debris, protect the
pump from excessive wear and clogging by sus
pending it in a perforated barrel or culvert pipe. If
the bottom is heavily sludge‐covered, rest the
pump on support blocks or suspend it from a raft
or similar device near the surface of the liquid. See
Figure B-1 for typical pump installations.
All liquid entering the pump must pass through a
strainer screen. Any spherical solids which pass
through the screen will pass through the pump.
BY BAIL IN PERFORATED CULVERT PIPE ON SUPPORTS
Figure B-1 Typical Pump Installations
Piping
No suction piping is required in a standard installa
tion.
These pumps are provided with a suction strainer
to prevent large solids from clogging the impeller.
If required, the strainer can be removed and the
pump suction “staged” to the discharge of another

OM-06258 S SERIES PUMPS
PAGE B - 4 INSTALLATION
pump, allowing one pump to feed the other on high
discharge head applications.
To determine the size of the discharge connection,
see Table B-1, Pump Specifications. Either
hose or rigid pipe may be used. To facilitate mobil
ity and maintenance, it is recommended that the
discharge line be fitted with a quick disconnect fit
ting near the pump. The discharge line must be in
dependently supported to avoid strain and vibra
tion on the pump.
Either hose or rigid pipe may be used to make dis
charge connections. For maximum pumping ca
pacity, keep the line as short and straight as pos
sible. Elbows and fittings used in discharge lines
increase friction loss, minimize their use.
It is recommended that a check valve or throttling
valve be installed in the discharge line to control si
phoning or back flow when the pump is shut off.
ELECTRICAL CONNECTIONS
Install and operate this pump in accor
dance with the National Electrical Code
and all local codes. Have a qualified
electrician perform all checks and con
nections in this section.
Never attempt to alter the length of the
pump motor cable or to repair it with a
splice. The power cable and pump mo
tor must be kept completely waterproof.
Serious damage to the pump and injury
or death to personnel can result from
any alteration to the cable.
Control Box Installation
The pump is designed to be operated
through the control box furnished with
the pump. The control box provides
overload protection and power control.
Do not connect the pump motor directly
to the incoming power lines.
The control box is a rainproof enclosure with a pad
lockable front cover. The enclosure is not de
signed to be watertight, and should not be sub
merged. Refer to the control box manual for enclo
sure dimensions and parts.
Secure the control vertically on a level surface,
above flood level. The box should be easily acces
sible to the operator, and located close enough to
the pump to avoid excessive voltage drop due to
cable length (see Pump Power Cable Connec
tion). After the box is installed, make certain the
front cover latches properly.
Failure to mount the control box vertically
on a level surface may affect operation of
the pump controls.
Field Wiring Connections (Incoming Power)
The electrical power used to operate
this pump is high enough to cause inju
ry or death. Obtain the services of a
qualified electrician to make all electri
cal connections. Make certain that the
pump and enclosure are properly
grounded; never use gas pipe as an
electrical ground. Be sure that the in
coming power matches the voltage and
phase of the pump and control before
connecting the power source. Do not
run the pump if the voltage is not within
the limits.
Do not connect the pump motor directly
to the incoming power lines. The pump
motor is designed to operate through a
Gorman‐Rupp approved control box
which provides overload protection and
power control; otherwise, the pump
warranty will be voided. Make certain
that the pump and control box are prop

S SERIES PUMPS OM-06258
PAGE B - 5INSTALLATION
erly grounded. Install and operate the
control box in accordance with the Na
tional Electric Code and all local codes.
Failure to follow these could result in in
jury or death to personnel.
Field wiring is not provided with the pump, and
must be supplied by the user. The field wiring must
be of the proper size and type to ensure an ade
quate voltage supply to the pump. Voltage avail
able at the motor must be within the range indi
cated in Table B‐3.
To calculate the voltage available at the motor, pro
ceed as follows:
a. Measure the voltage across the incoming
lines (1 & 2 for single phase, 1 & 2, 2 & 3, and 1
& 3 for three phase) while the pump is oper
ating at full capacity. Refer to the literature
supplied with the control box for power supply
connections.
b. Next, subtract the motor cable voltage drop
(see Table 4, Pump Power Cable Specifica
tions).
c. Do not continue to operate the pump if this
voltage is not within the recommended limits.
Obtain the services of a qualified electrician to
determine the correct field wiring size and oth
er details to ensure an adequate voltage sup
ply to the pump.
Table B‐3. Pump Voltage Requirements
NOMINAL
VOLTAGE
3460 420 500
PHASE
MINIMUM
VOLTAGE
MAXIMUM
VOLTAGE
575 3 520 630
Make certain all connections are tight and that
cable entry points are rainproof. Support the cable
weight, if required, to prevent excessive strain on
cable clamps and cable.
Grounding Methods
Electrically ground the installation before connect
ing the field wiring to the control box. Install a
grounding terminal to the enclosure and connect
it to a properly embedded electrode.
The material used for the electrode must be an ex
cellent conductor of electricity, such as copper. If
iron or steel is used, it must be galvanized or other
wise metal plated to resist corrosion. Do not coat
the electrode with any material of poor conductiv
ity, such as paint or plastic.
The electrode must conform to the recommenda
tions of N.E.C. ARTICLE 250. Follow all installation
requirements of the N.E.C., and all applicable
codes. See Figure B-3 for some suggested
grounding methods.
ROCK
8 FEET
(2,4 M)
3/4 INCH (19,1
MM) NOMINAL
DIAMETER
(MINIMUM)
3/4 INCH (19,1 MM)
NOMINAL DIAMETER
(MINIMUM) 8 FEET
(2,4 M) LONG
SOIL
SOIL
SOIL
1/4 INCH (6,4 MM)
STEEL PLATE 2 SQ.
FEET (1858,1 SQ. CM)
SURFACE AREA
(MINIMUM)
a) PLATE ELECTRODE b) DRIVEN ELECTRODE c) BURIED ELECTRODE
Figure B-3. Suggested Grounding Methods
a. Plate Electrode: An iron or steel plate, 1/4
inch (6,4 mm) thick, completely impeded in
the ground. The plate must present a surface
area of at least 2 square feet (1858,1 sq. cm.).

OM-06258 S SERIES PUMPS
PAGE B - 6 INSTALLATION
b. Driven Electrode: A rod or pipe, 3/4 inch
(19,1 mm) in diameter minimum, 8 feet (2,4 m)
long, completely driven into the ground.
c. Buried electrode: If rock or stone prevents
embedding the full 8 foot (2,4 m) length of the
ground rod, bury it horizontally in a trench.
Space the ground rod or plates at least 6 feet
(1,8) from any other electrode or ground rod,
such as those used for signal circuits, radio
grounds, lightning rods, etc.
The earth surrounding the ground rod or plate
must contain enough moisture to make a
good electrical connection. In dry or sandy
areas, pour water around the rod, or consult
qualified personnel to devise a method of im
proving the connections.
The electrical power used to operate
this pump is high enough to cause inju
ry or death. Make certain that the control
box is properly grounded after installa
tion.
Refer to the literature accompanying the control
box for field wiring connections.
Pump Power Cable Connections
The electrical power used to operate
this pump is high enough to cause inju
ry or death. Obtain the services of a
qualified electrician to make all electri
cal connections. Make certain that in
coming power to the control box is in the
OFF position and locked out, or that the
power supply to the control box has
been otherwise cut off and locked out,
before connecting power or accessory
cables.
The pump is provided with a 50 ft. (15,2 m) power
cable (see Table B-4 for standard power cable
specifications). If a longer cable is required, an op
tional cable assembly must be ordered from the
factory. Splicing of the power cable is not recom
mended by the Gorman‐Rupp Company due to
safety and warranty considerations.
Never attempt to alter the length or re
pair any power cable with a splice. The
pump motor and cable must be com
pletely waterproof. Injury or death may
result from alternations.
Table B‐4. Pump Power Cable Specifications
Pump
Model
Voltage/
Phase
A.W.G
Cable
Size
Conductor
Dia.
Inches
(mm)
DC
Resistance
(ohms) at
25C (77F)
per 1000 ft.
(305 m)
Cable
O.D.
Inches
(mm)
Amp
Rating
(See
Note
Below)
Cable
Type 
NOTE: * Amp Rating at 30C (86F)  Canada Use Type SOW Cable
** Amp Rating at 40C (104F)
Voltage
Drop
per 100 ft.
(30,5m) at
Max. Load
GGC 2.90
575/3
S8A 1 1.51 (38) .38 (9,7) 142** 0.13
2.69
460/3 2/0 1.75 (44) .48 (12,2) 189** 0.09
When necessary to change or connect the pump
power cable to the control box, make certain the in
coming power is OFF and LOCKED OUT, Make
certain the control box is PROPERLY GROUNDED
and that the electrical data on the control matches
the motor name plate data.

S SERIES PUMPS OM-06258
PAGE B - 7INSTALLATION
Connect the pump power cable to the control box
as shown in the wiring diagrams in the control box
manual. Use conduit or cable clamps to secure the
power cable to the control box. Make certain that
all connections are tight and that cable entry points
are rainproof.
NOTE
The power cable furnished with the pump includes
three electrical conductors (white, red, and black),
two grounding conductors (green) and one ground
check conductor (yellow).The yellow ground
check lead is used in conjunction with customer‐
supplied ground monitoring equipment. If this
equipment is not used, the yellow lead should be
used as a ground conductor.
Control Box Specifications
Any control box used to operate the
pump must be approved by the Gor
man‐Rupp Company for the application.
Motor Cable Grounding Test
Do not connect the pump control cable
to the control box or incoming voltage
before verifying the pump ground;
otherwise, personnel will be exposed to
serious injury or death.
Using a volt‐ohm meter, connect one lead to the
motor cable green/yellow ground lead. Connect
the other lead to an uninsulated point on the pump
body. The test circuit should close.
If the test circuit does not close, there is a defect in
the cable or motor which must be corrected.
Control Box Connections
This pump is shipped completely wired for the volt
age shown on the name plate, and is ready for op
eration through an approved control box.
Ground and wire the control box in accordance
with the instructions accompanying it.
NOTE
For reference, internal motor wiring connections
are shown in Maintenance and Repair - Section
E.
Liquid Level Devices
The standard pump is not furnished with a means
to automatically regulate liquid level. However, the
pump may be controlled to perform filling or dewa
tering functions by using either of the following op
tional sensing devices (see Figure B-4):
Diaphragm Type: two fixed‐position sen
sors (upper and lower) each contain a dia
phragm which flexes with changes in liquid
level, thus activating an enclosed miniature
switch.
Bulb (Float) Type: a bulb raises or lowers
(floats) with the liquid level, thus activating
an enclosed miniature switch.
The liquid level circuitry may be prewired as a fac
tory option, or easily added to the standard control
box in the field by qualified personnel. The unit is
complete except for the remote float switches. For
installation and operation, see the detailed instruc
tions included with the optional package.
Liquid level devices must be positioned far
enough apart to allow 10 minutes between
starts. If the pump motor cycles more than
6 starts per hour, it will over‐heat, resulting
in damage to the motor windings or control
box components.
Other types of liquid level devices may also be
used. Consult the factory for the liquid level device
best suited for your application.
If the pump requires liquid level devices,
install the liquid level devices and connect
them to the control box in accordance with
the instructions accompanying the de
vices.

OM-06258 S SERIES PUMPS
PAGE B - 8 INSTALLATION
PUMP
CONTROL BOX
LIQUID LEVEL
RANGE
ON (FILLING)
TO LEVEL CONTROL CIRCUIT
IN MAIN CONTROL BOX
BULB (FLOAT TYPE)
OFF
DEWATERING
PUMP
CONTROL BOX
TO LEVEL CONTROL CIRCUIT
IN MAIN CONTROL BOX
LIQUID LEVEL
RANGE
OFF
DEWATERING
ON (FILLING)
DIAPHRAGM TYPE
Figure B-4. Liquid Level Devices
The internal wiring of the sensing devices
are different for filling and dewatering func
tions. Be sure to follow the instructions in
cluded with the option before making wir
ing connections.
WIRING DIAGRAMS
Refer to the appropriate wiring diagram in the liter
ature accompanying the control box when making
electrical connections.

S SERIES PUMPS OM-06258
PAGE C - 1OPERATION
OPERATION - SECTION C
GENERAL INFORMATION
Review all SAFETY information in Section A.
This pump is designed to handle most
non‐volatile, non‐flammable liquids. Do
not attempt to pump any liquids for
which your pump is not approved, or
which may damage the pump or endan
ger personnel as a result of pump fail
ure. Consult the factory for specific ap
plication data.
Follow the instructions on all tags, labels and de
cals attached to the pump.
Pump Performance
Since operation of the pump motor is de
pendent upon the quality and performance
of the electrical controls, the pump warran
ty is valid only when controls have been
specified or provided by The Gorman‐
Rupp Company.
Refer to the performance curve in Maintenance
and Repair - Section E for the specific perfor
mance for your pump.
Control Box
A control box is provided to facilitate operation of
the pump. It contains controls for starting and stop
ping the pump, and provides overload protection
for the pump motor. The pump control may be
equipped with an optional automatic liquid level
sensing device, in which case those circuits are
also contained within the control box.
The pump motor and control box are not
designed to be explosion‐proof. Do not
operate in an explosive atmosphere.
Any control box used to operate the
pump must be approved by the Gor
man‐Rupp Company for the application.
Improper location of a non‐explosion
proof control box could result in de
struction of equipment, injury or death
to personnel.
See the operating instructions furnished with the
control box, and with other optional accessories
and controls, before attempting to start the pump.
PUMP OPERATION
Liquid Temperature and Overheating.
Overheated pumps can cause severe
burns and injury. If the pump becomes
overheated:
1. Stop the pump immediately.
2. Lock out the power to the control
panel to ensure that the pump will
remain inoperative.
3. Allow the pump to completely cool
if overheated.
4. Close the discharge valve (if
used).
5. Refer to instructions in this manual
before restarting the pump.
Overheating can occur if the pump is misapplied;
if it is started more than 6 times within one hour; if
the temperature of the liquid being pumped ex
ceeds the temperature for which the pump was de
signed, if the control box fails to provide overload

OM-06258 S SERIES PUMPS
PAGE C - 2 OPERATION
or thermal protection, or if the pump is operated
against a closed discharge valve for an extended
period of time.
Do not start the pump more than 6 times
per hour. If the motor does not cool be
tween starts it will overheat, resulting in
damage to the motor windings.
As a safeguard against rupture or explosion due to
heat, models equipped with oil‐lubricated motors
are fitted with a pressure relief valve which will open
if vapor pressure within the pump motor reaches a
critical point. Always terminate power to the pump
and control before investigating pump or control
box problems.
Approach the pump cautiously after it
has been running. Although the motor is
cooled by the liquid being pumped, nor
mal operating temperatures can be high
enough to cause burns. The tempera
ture will be especially high if operated
against a closed discharge valve. Never
operate against a closed discharge
valve for long periods of time.
If overheating does occur, stop the pump immedi
ately and allow it to cool before servicing it. Ap
proach any overheated pump cautiously.
Overheated pumps can cause severe
burns and injuries. If overheating of the
pump occurs:
1. Stop the pump immediately.
2. Ventilate the area.
3. Allow the pump to completely cool.
4. Check the temperature before ser
vicing.
5. Vent the pump slowly and cau
tiously
6. Refer to instructions in this manual
before restarting the pump.
It is recommended that the pressure relief valve as
sembly be replaced at each overhaul, or any time
the pump motor overheats and activates the valve.
Never replace this valve with a substitute which
has not been specified or provided by the Gorman‐
Rupp Company.
Impeller Rotation
Check impeller rotation as follows before operation
to ensure that the impeller is rotating in the correct
direction.
While checking impeller rotation, secure
the pump to prevent the power cable from
coiling.
Suspend the pump from the lifting device fitted on
the pump. Apply power briefly and note the direc
tion of pump kickback. As viewed from the top, the
pump should kick in a counterclockwise direc
tion; this will indicate that impeller rotation is cor
rect.
If the pump kicks in a clockwise direction, impeller
rotation is incorrect. If the pump is powered by a
three‐phase motor, have a qualified electrician in
terchange the control box connections of any two
pump motor power leads. Re‐check pump kick
back; it should now be in a counterclockwise direc
tion.
If rotation is incorrect on a single‐phase motor, con
tact the factory before installing the pump.
The electrical power used to operate

S SERIES PUMPS OM-06258
PAGE C - 3OPERATION
this pump is high enough to cause inju
ry or death. Make certain that incoming
power is off and locked out before inter
changing motor leads.
DIRECTION OF
KICKBACK
AT STARTUP
Figure C-1. Checking Pump Rotation
STARTING, STOPPING, AND
OPERATIONAL CHECKS
Starting
Do not attempt to operate the pump until
impeller rotation has been checked; im
proper rotation will affect pump perform
ance and may damage the pump.
Follow the instructions accompanying the control
box, start the pump, and run any recommended
checks.
Never start the pump more than 6 times per
hour. If the pump motor does not cool be
tween starts, it will over‐heat, resulting in
damage to the motor windings.
Stopping
Follow the instructions accompanying the control
box for stopping the pump.
On pumps equipped with a motor ther
mal protector, the integral thermal over
load device will shut off the motor if the
temperature rises above design limits.
When the pump cools and the tempera
ture falls below these limits, the motor
will restart automatically. To avoid the
hazards of an unexpected motor start‐
up, do not attempt to handle or service
the pump unless all power to the motor
has been shut off and locked out at the
control box; otherwise, serious person
al injury could result.
During motor shutoff by the thermal
overload device, control box circuits re
main live. Do not attempt to service any
control box components unless incom
ing power has been shut off.
To stop the pump, turn the control handle OFF,
thereby opening the circuit breakers. This does
not terminate incoming power through the field
wiring connected to the control box.
After stopping the pump, be sure to perform all re
quired maintenance and preservation procedures.
Operational Checks
To detect minor problems, check the pump for
proper operation when it is first started, and at peri
odic intervals during operation.

OM-06258 S SERIES PUMPS
PAGE C - 4 OPERATION
To avoid serious damage to the pump,
check for unusual noises or excessive vi
bration while the pump is running. If noise
or vibration is excessive, stop operation
and refer to the troubleshooting chart in the
maintenance and repair manual.
The suction inlet or impeller may become clogged
with debris. In some cases, stopping the pump
momentarily may backflush this blockage. If back
flushing does not clear the debris, remove the
pump from the sump or wet well and clear manu
ally.
Never introduce air or steam pressure
into the pump casing to remove a block
age. This could result in personal injury
or damage to the equipment. If back
flushing is absolutely necessary, limit
liquid pressure input to 50% of the maxi
mum permissible operating pressure
shown in the pump performance curve
(refer to the accompanying Parts List
Manual).
Check the pump for overheating. Overheating can
occur if the pump is misapplied, required to start
repeatedly, if the control box fails to provide over
load or thermal protection, or if the pump is oper
ated against a closed discharge valve for an ex
tended period of time.
Do not start the pump more than 6 times
per hour. If the motor does not cool be
tween starts it will overheat, resulting in
damage to the motor windings.
Check the oil level(s) as indicated in the following
LUBRICATION section.
COLD WEATHER PRESERVATION
Do not attempt to thaw the pump by us
ing a torch or other source of flame. This
could damage gaskets, O‐rings or heat
the oil in the seal housing above critical
temperatures, causing the pump to rup
ture or explode.
The pump will not freeze as long as the casing is
submerged in liquid. If the casing is not sub
merged, or if the liquid begins to freeze, remove the
pump from the sump or wet well and dry it thor
oughly. Run the pump for two or three minutes to
dry the inner walls.
If the pump does freeze while it is out of the liquid,
submerge it until thawed; if the liquid is near freez
ing, the pump must be submerged for an extended
period of time. Check thawing by starting the pump
and checking that the shaft rotates freely. If the
pump remains frozen, allow additional thawing
time before attempting to restart.
If submerging does not thaw the pump, move it
into a warm area until completely thawed.
LUBRICATION
Do not remove plates, covers, gauges,
pipe plugs or fittings from an over
heated pump. Vapor pressure within the
pump can cause parts being disen
gaged to be ejected with great force. Al
low the pump to completely cool before
servicing.
On a new pump, check the oil level in both seal and
motor cavities before initial startup, and drain and
replace the oil after the first 200 hours of operation.
Following this, check the oil level in the seal cavity
after the first two weeks of operation, and every