GORMAN-RUPP PUMPS RP Series User manual

OM-06203-01
September 9, 2008
Rev. A 11‐08‐17
GORMAN‐RUPP PUMPS
www.grpumps.com
2008 Gorman‐Rupp Pumps Printed in U.S.A.
INSTALLATION, OPERATION,
AND MAINTENANCE MANUAL
WITH PARTS LIST
RP SERIES PUMP
MODEL
RP6C60
Including FRAME And SAE Models

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:
The engine exhaust from this
product contains chemicals
known to the State of California to
cause cancer, birth defects or
other reproductive harm.

TABLE OF CONTENTS
i
INTRODUCTION PAGE I - 1.................................................
SAFETY ‐ SECTION A PAGE A - 1............................................
INSTALLATION - SECTION B PAGE B - 1....................................
PREINSTALLATION INSPECTION PAGE B - 1............................................
Battery Installation PAGE B - 1.....................................................
ELECTRICAL CONNECECTIONS (ELECTRIC MOTOR DRIVEN UNITS) PAGE B - 1...........
Field Wiring Connections (Incoming Power) PAGE B - 2...............................
POSITIONING PUMP PAGE B - 2.......................................................
Lifting PAGE B - 3.................................................................
Mounting PAGE B - 3.............................................................
SUCTION AND DISCHARGE PIPING PAGE B - 3.........................................
Materials PAGE B - 3..............................................................
Line Configuration PAGE B - 3......................................................
Connections to Pump PAGE B - 3..................................................
Gauges PAGE B - 3...............................................................
SUCTION LINES PAGE B - 3...........................................................
Fittings PAGE B - 4...............................................................
Strainers PAGE B - 4..............................................................
Sealing PAGE B - 4...............................................................
Suction Lines In Sumps PAGE B - 4.................................................
Suction Line Positioning PAGE B - 4................................................
DISCHARGE LINES PAGE B - 5........................................................
Siphoning PAGE B - 5.............................................................
Valves PAGE B - 5................................................................
ALIGNMENT PAGE B - 5..............................................................
Factory Installed Engine Driven Units PAGE B - 5.....................................
Electric Motor Driven Units PAGE B - 5..............................................
Coupled Drives PAGE B - 6........................................................
V‐belt Drives PAGE B - 6...........................................................
V‐BELT TENSIONING PAGE B - 7......................................................
General Rules of Tensioning PAGE B - 7.............................................
Tension Measurement PAGE B - 7..................................................
AUTO‐START PAGE B - 9.............................................................
Float Switch Installation PAGE B - 9.................................................
Submersible Transducer Installation PAGE B - 9......................................
Submersible Connections PAGE B - 11...............................................
OPERATION - SECTION C PAGE C - 1......................................
OPERATION OF FACTORY‐EQUIPPED ELECTRIC MOTOR DRIVEN UNITS PAGE C - 1.......
Component Function PAGE C - 1...................................................
Rotation PAGE C - 2..............................................................
Priming PAGE C - 2...............................................................
OPERATION OF FACTORY‐EQUIPPED ENGINE MOTOR DRIVEN UNITS PAGE C - 2.........
Before Starting PAGE C - 2........................................................
Manual Starting (Deutz Powered Units) PAGE C - 2...................................
Manual Starting (John Deere and Caterpillar Powered Units) PAGE C - 3................

TABLE OF CONTENTS
(continued)
ii
Automatic Starting (Deutz Powered Units) PAGE C - 3.................................
Automatic Starting (John Deere and Caterpillar Powered Units) PAGE C - 4..............
PRIMING PAGE C - 4.................................................................
ROUTINE OPERATION (Engine Driven Units) PAGE C - 4.................................
OPERATION IN EXTREME HEAT (Engine Driven Units) PAGE C - 5.........................
OPERATIONAL CHECKS (All Models) PAGE C - 5........................................
Leakage PAGE C - 5..............................................................
Pump Vacuum Check PAGE C - 5..................................................
Vacuum Pump Discharge Line PAGE C - 5...........................................
Liquid Temperature And Overheating PAGE C - 5.....................................
Strainer Check PAGE C - 5.........................................................
STOPPING (Electric Motor Driven Units) PAGE C - 6......................................
STOPPING (Engine Driven Units) PAGE C - 6............................................
Manual Stopping (Deutz Powered Units) PAGE C - 6..................................
Manual Stopping (John Deere Powered Units) PAGE C - 6.............................
Automatic Stopping PAGE C - 6....................................................
Safety Shutdown System PAGE C - 6...............................................
PERIODIC CHECKS (All Models) PAGE C - 7............................................
Seal Cavity And Bearing Lubrication PAGE C - 7......................................
Bearing Temperature Check PAGE C - 7.............................................
PERIODIC CHECKS (Engine Driven Units) PAGE C - 7....................................
Engine Fuel Filter PAGE C - 7......................................................
Engine Oil PAGE C - 7.............................................................
Belts PAGE C - 7.................................................................
COLD WEATHER PRESERVATION (All Models) PAGE C - 7...............................
TROUBLESHOOTING - SECTION D PAGE D - 1..............................
PREVENTIVE MAINTENANCE PAGE D - 3...............................................
PUMP MAINTENANCE AND REPAIR ‐ SECTION E PAGE E - 1.................
PERFORMANCE CURVES PAGE E - 1..................................................
PARTS LISTS:
Pump Models PAGE E - 3.........................................................
Pump Model (SAE 4/10) PAGE E - 5................................................
Pump Model (FRAME) PAGE E - 7..................................................
Vacuum Pump Assembly PAGE E - 9...............................................
Priming Chamber Kit PAGE E - 10...................................................
Check Valve Kit PAGE E - 11........................................................
Drive Assembly (Factory‐Equipped Engine Driven Units) PAGE E - 12....................
PUMP MAINTENANCE AND REPAIR PAGE E - 13.........................................
DISCHARGE CHECK VALVE DISASSEMBLY AND REASEMBLY PAGE E - 14.................
Discharge Check Valve Removal and Disassembly PAGE E - 14.........................
Discharge Check Valve Assembly and Installation PAGE E - 14..........................
PRIMING CHAMBER DISASSEMBLY AND REASEMBLY PAGE E - 14........................
Suction Spool and Priming Chamber Removal and Disassembly PAGE E - 14.............
Suction Spool and Priming Chamber Assembly and Installation PAGE E - 15..............
VACUUM PUMP MAINTENANCE AND REPAIR PAGE E - 15................................
Vacuum Pump Removal PAGE E - 15................................................
Vacuum Pump Disassembly PAGE E - 15.............................................

TABLE OF CONTENTS
(continued)
iii
Vacuum Pump Reassembly PAGE E - 16.............................................
Vacuum Pump Installation PAGE E - 18...............................................
Vacuum Pump Lubrication PAGE E - 18..............................................
PUMP AND SEAL DISASSEMBLY AND REASSEMBLY PAGE E - 18.........................
Pump Casing Removal PAGE E - 18.................................................
Impeller Removal PAGE E - 19......................................................
Seal Removal PAGE E - 19..........................................................
Back Plate Removal PAGE E - 19....................................................
Separating Pump Frame And Drive Assembly From Engine PAGE E - 20.................
Pump Shaft and Bearing Removal and Disassembly PAGE E - 20........................
Bearing Cleaning And Inspection PAGE E - 20........................................
Pump Shaft and Bearing Reassembly and Installation PAGE E - 21......................
Drive Assembly Installation PAGE E - 22..............................................
Seal Reassembly and Installation PAGE E - 22........................................
Impeller Installation PAGE E - 24.....................................................
Pump Casing and Wear Ring Installation PAGE E - 25..................................
PUMP LUBRICATION PAGE E - 25......................................................
Seal Assembly PAGE E - 25.........................................................
Bearings PAGE E - 25..............................................................
Engine PAGE E - 25................................................................

OM-06203
RP SERIES
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. This Installation, Operation, and Mainte
nance manual is designed to help you achieve the
best performance and longest life from your Gor
man‐Rupp pump.
This pump is an RP Series, priming‐assisted cen
trifugal model. It is designed for handling non‐vola
tile, non‐flammable liquids containing specified en
trained solids. The basic material of construction is
gray iron.
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
which are not covered in this manual or in other lit
erature accompanying the 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 en
gine, contact the engine manufacturer's local
dealer or representative.
The following are used to alert personnel to proce
dures which require special attention, 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 de
scribe 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.

RP SERIES OM-06203
PAGE A - 1SAFETY
SAFETY ‐ SECTION A
This information applies to RP Series
pumps. Refer to the manual accompa
nying the engine or power source be
fore attempting to begin operation.
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. Shut down the engine and discon
nect the positive battery cable, or
lock out incoming power to the mo
tor and take precautions to ensure
that the pump will remain inopera
tive.
3. Allow the pump to completely cool
if overheated.
4. Check the temperature and make
sure the pump is cool before open
ing any covers, plates, or plugs.
5. Close the suction and discharge
valves.
6. Vent the pump slowly and cau
tiously.
7. Drain the pump.
This pump is designed to handle most
non‐volatile, non‐flammable liquids
containing specified entrained solids.
Do not attempt to pump volatile, corro
sive, or flammable liquids which may
damage the pump or endanger person
nel as a result of pump failure.
Use lifting and moving equipment in
good repair and with adequate capacity
to prevent injuries to personnel or dam
age to equipment. Attach lifting equip
ment to the lifting device fitted to the
pump. If chains or cable are wrapped
around the pump to lift it, make certain
that they are positioned so as not to
damage the pump, and so that the load
will be balanced. The bail is intended for
use in lifting the pump assembly only.
Suction and discharge hoses and pip
ing must be removed from the pump be
fore lifting.
After the pump has been installed, make
certain that the pump and all piping or
hose connections are tight, properly
supported and secure before operation.
Do not operate the pump against a
closed discharge valve. If operated
against a closed discharge valve, pump
components will deteriorate, and the
liquid could come to a boil, build pres
sure, and cause the pump casing to rup
ture or explode. Momentary closure of a
discharge valve is acceptable only
when required for startup or shutdown
procedures.
Do not remove plates, covers, gauges,

RP SERIESOM-06203
PAGE A - 2 SAFETY
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 cool completely before
servicing.
Do not operate the pump without a
guard in place over the rotating parts.
Exposed rotating parts can catch cloth
ing, fingers, or tools, causing severe in
jury to personnel.
This pump may be used to handle mate
rials which could cause illness through
direct exposure or emitted fumes. Wear
adequate protective clothing when
working on the pump or piping.
This pump may be equipped with auto
matic liquid level controls, and there
fore subject to automatic restart. Keep
hands and clothing away from the unit to
prevent injury during automatic opera
tion. Shut down the engine and discon
nect the positive battery cable, or lock
out incoming power to the motor before
performing any maintenance. Failure to
do so may result in serious personal in
jury.
Make sure the pump is level. Lower jack
stands and chock the wheels, if so
equipped. Use caution when positioning
the skid‐mounted unit to prevent damage
to the fuel tank.
If the pump is powered by an electric
motor, the motor must be operated
through a control box that provides
overload protection and power control.
Do not connect the pump motor directly
to the incoming power lines.
If the pump is powered by an electric
motor, the electrical power high enough
to cause injury or death. Obtain the ser
vices of a qualified electrician to make
all electrical connections. Make certain
that the pump is properly grounded;
never use gas pipe as an electrical
ground. Be sure that the incoming pow
er matches the voltage and phase of the
motor and control before connecting to
the incoming power. Do not run the
pump if the voltage is not within the lim
its.
If the pump is powered by an electric
motor, the electrical power high enough
to cause injury or death. Make certain
that the handle on 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 attempting to open or service the
pump assembly. Tag electrical circuits
to prevent accidental start‐up.
If the pump is powered by an electric
motor, all electrical connections must
be in accordance with The National
Electric Code and all local codes. If
there is a conflict between the instruc

RP SERIES OM-06203
PAGE A - 3SAFETY
tions provided and N.E.C. Specifica
tions, N.E.C. Specifications shall take
precedence. All electrical equipment
supplied with this pump was in confor
mance with N.E.C. requirements in ef
fect on the date of manufacture. Failure
to follow applicable specifications, or
substitution of electrical parts not sup
plied or approved by the manufacturer,
can result in severe injury or death and
void warranty.
Obtain the services of a qualified elec
trician to troubleshoot, test and/or ser
vice the electrical components of this
pump.
If the pump is powered by an internal
combustion engine, do not operate the
engine in an explosive atmosphere.
When operating an internal combustion
engine in an enclosed area, make sure
exhaust fumes are piped to the outside.
These fumes contain carbon monoxide,
a deadly gas that is colorless, tasteless
and odorless.
If the pump is powered by an internal
combustion engine, the engine fuel
presents an extreme explosion and fire
hazard. Make certain that all fuel lines
are securely connected and free of
leaks. Never refuel a hot or running en
gine. Avoid overfilling the fuel tank. Al
ways use the correct type of fuel.
If the pump is powered by an internal
combustion engine, never tamper with
the governor to gain more power. The
governor establishes safe operating
limits that should not be exceeded. Re
fer to the Performance Curve in Section
E, Page E‐1 for the maximum continu
ous operating speed for this pump.
Pumps and related equipment must be
installed and operated according to all na
tional, local and industry standards.

RP SERIES OM-06203
PAGE B - 1INSTALLATION
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 ar
range 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 Gorman‐Rupp
distributor or the Gorman‐Rupp Company.
PREINSTALLATION INSPECTION
The pump assembly was inspected and tested be
fore shipment from the factory. Before installation,
inspect the pump for damage which may have oc
curred 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 hard
ware. Since gaskets tend to shrink after dry
ing, check for loose hardware at mating sur
faces.
c. Carefully read all tags, decals, and markings
on the pump assembly, and perform all duties
indicated. Note that the pump shaft rotates in
the required direction.
d. Check levels and lubricate as necessary. Re
fer to LUBRICATION in the Maintenance and
Repair Manual and perform duties as in
structed.
e. If the pump and/or power source have been
stored for more than 12 months, some of the
components or lubricants may have ex
ceeded their maximum shelf life. These must
be inspected or replaced to ensure maxi
mum pump service.
If the maximum shelf life has been exceeded, or if
anything appears to be abnormal, contact your
Gorman‐Rupp distributor or the factory to deter
mine the repair or updating policy. Do not put the
pump into service until appropriate action has
been taken.
Battery Installation (Engine Driven Units)
Unless otherwise specified on the pump order, the
engine battery is not included with engine driven
units.
Refer to the information accompanying the battery
and/or electrolyte solution for activation and charg
ing instructions.
Before installing the battery, clean the positive and
negative cable connectors, and the battery termi
nals. Secure the battery by tightening the
holddown brackets. The terminals and clamps
may be coated with petroleum jelly to retard corro
sion. Connect and tighten the positive cable first,
then the negative cable.
ELECTRICAL CONNECTIONS
(ELECTRIC MOTOR DRIVEN UNITS)
Rotation
The correct direction of pump rotation is indicated
by an arrow on the pump body or accompanying
decals. Reverse rotation could damage the pump
and adversely affect performance.
The pump must operate in the direction in
dicated by the arrow on the pump, or ac
companying decals. Reverse rotation
could damage the pump and adversely af
fect performance.

OM-06203 RP SERIES
PAGE B - 2 INSTALLATION
To check electric motor rotation, disconnect the
pump from the motor before checking motor
rotation. Operate the motor independently while
observing the direction of the motor shaft or cool
ing fan.
If rotation is incorrect on a three‐phase motor, have
a qualified electrician interchange any two of the
three phase wires to change direction.
Field Wiring Connections (Incoming Power)
Power used to operate electric motor
driven units is high enough to cause in
jury or death. Obtain the services of a
qualified electrician to make all electri
cal connections. Do not connect a motor
directly to the incoming power lines. Be
sure that the incoming power matches
the voltage and phase of the motor and
control before connecting the power
source. Do not run the motor if the volt
age is not within the limits.
The motor is designed to operate
through a control box which provides
overload protection and power control.
Make certain that the pump and control
box are properly grounded. Install and
operate the control box in accordance
with the National Electric Code and all
local codes. Failure to follow these in
structions could result in injury or death
to personnel.
Before connecting the control box to the incoming
power, check that the electrical service available
matches the motor requirements stamped on the
motor nameplate.
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 motor. Voltage avail
able at the motor must be within the range indi
cated in Table B-1.
To calculate the voltage available at the motor, pro
ceed as follows:
a. Measure the voltage across the lines on the
load side of the control box (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.
Do not continue to operate the motor if this voltage
is not within the recommended limits. Obtain the
services of a qualified electrician to determine the
correct field wiring size and other details to ensure
an adequate voltage supply to the motor.
Table B-1. Pump Voltage Requirements
NOMINAL
VOLTAGE
3
3
230
460
210
420
250
500
PHASE
MINIMUM
VOLTAGE
MAXIMUM
VOLTAGE
575 3 520 630
3380 340 418
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.
POSITIONING 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
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.

RP SERIES OM-06203
PAGE B - 3INSTALLATION
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.
The pump assembly can be seriously
damaged if the chains or cables used to lift
and move the unit are improperly wrapped
around the pump.
Mounting
Locate the pump in an accessible place as close as
practical to the liquid being pumped. Level mount
ing is essential for proper operation. The pump
may have to be supported or shimmed to provide
for level operation and eliminate vibration.
For engine driven units, the pump must be posi
tioned as level as possible to ensure sufficient lubri
cation and fuel supply to the engine.
If the pump has been mounted on a moveable
base, make certain the base is stationary by setting
the brake and blocking the wheels before attempt
ing to operate the pump.
If the pump has been mounted on a mov
able base, do not attempt to operate the
pump unless the unit is level. Be sure
the leveling stands are positioned on a
solid surface, and the wheels are
chocked.
SUCTION AND DISCHARGE PIPING
Pump performance is adversely effected by in
creased suction lift, discharge elevation, and fric
tion losses. See the performance curve and oper
ating range shown on Page E‐1 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, rein
forced type to prevent collapse under suction. Us
ing piping couplings in suction lines is not recom
mended.
Line Configuration
Keep suction and discharge lines as straight as
possible to minimize friction losses. Make mini
mum use of elbows and fittings, which substan
tially 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 ex
actly with the pump port. Never pull a pipe line into
place by tightening the flange bolts and/or cou
plings.
Lines near the pump must be independently sup
ported 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 prim
ing, the suction line must be as short and direct as

OM-06203 RP SERIES
PAGE B - 4 INSTALLATION
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 in
stalled with the flat part of the reducers uppermost
to avoid creating air pockets. Valves are not nor
mally used in suction lines, but if a valve is used,
install it with the stem horizontal to avoid air pock
ets.
Strainers
Be certain to use the strainer furnished with the
pump; any spherical solids which pass through the
strainer will also pass through the pump itself.
If a strainer not furnished with the pump 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.
Refer to the performance curves in Section E, Page
E-1 for the solids handling capabilities of this
pump.
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 rec
ommendations 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 di
ameter 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 suc
tion inlet because the inflow will carry air down into
the sump, and air entering the suction line will re
duce pump efficiency.
If it is necessary to position inflow close to the suc
tion inlet, install a baffle between the inflow and the
suction inlet at a distance 1-1/2 times the diame
ter of the suction pipe. The baffle will allow en
trained 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 dis
tance 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 B-1
shows recommended minimum submergence vs.
velocity.
Although not recommended, the vacuum assisted
priming feature allows the pump to be operated
temporarily in a “slurping” application with varying
water levels.
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).

RP SERIES OM-06203
PAGE B - 5INSTALLATION
Figure B-1. Recommended Minimum Suction Line Submergence vs. Velocity
DISCHARGE LINES
Siphoning
Do not terminate the discharge line at a level lower
than that of the liquid being pumped unless a si
phon breaker is used in the line. Otherwise, a si
phoning action causing damage to the pump
could result.
Valves
This pump is designed with a check valve in the
discharge line.
If a throttling valve is desired in the discharge line,
use a valve as large as the largest pipe to minimize
friction losses. Never install a throttling valve in a
suction line.
With high discharge heads, it is recommended that
a throttling valve be installed in the discharge line
to protect the pump from excessive shock pres
sure and reverse rotation when it is stopped.
If the application involves a high discharge
head, gradually close the discharge
throttling valve before stopping the pump.
ALIGNMENT
Factory Installed Engine Driven Units
The alignment of the pump and engine is critical for
trouble‐free mechanical operation. Refer to Sec
tion E, Maintenance and Repair, for detailed
alignment information.
Electric Motor Driven Units
The alignment of the pump and its power source is
critical for trouble‐free mechanical operation. RP
Series electric motor driven pumps utilize both a
flexible coupling for connection to the motor and a
V‐belt drive to power the integral diaphragm vacu
um pump. Both the motor and pump must be
mounted so that their shafts are aligned with and

OM-06203 RP SERIES
PAGE B - 6 INSTALLATION
parallel to each other. It is imperative that alignment
be checked after the pump and piping are in
stalled, and before operation.
NOTE
Check Rotation, Section C, before final alignment
of the pump.
When mounted at the Gorman‐Rupp factory, the
motor and pump are aligned before shipment.
Misalignment will occur in transit and handling.
Pumps must be checked and realigned before
operation. Before checking alignment, tighten the
foundation bolts. The pump casing feet and/or
pedestal feet, and the motor mounting bolts
should also be tightly secured.
When checking alignment, shut down
incoming power and lock it out to en
sure that the pump will remain inopera
tive.
Adjusting the alignment in one direction
may alter the alignment in another direc
tion. Check each procedure after altering
alignment.
Coupled Drives
When using couplings, the axis of the motor must
be aligned to the axis of the pump shaft in both the
horizontal and vertical planes. Most couplings re
quire a specific gap or clearance between the driv
ing and the driven shafts. Refer to the coupling
manufacturer's service literature.
Align spider insert type couplings by using calipers
to measure the dimensions on the circumference
of the outer ends of the coupling hub every 90.
The coupling is in alignment when the hub ends
are the same distance apart at all points (see Fig
ure B-2).
Figure B-2. Aligning Spider‐Type Couplings
Align non‐spider type couplings by using a feeler
gauge or taper gauge between the coupling halves
every 90. The coupling is in alignment when the
hubs are the same distance apart at all points (see
Figure B-3).
Figure B-3. Aligning Non‐Spider Type
Couplings
Check parallel adjustment by laying a straightedge
across both coupling rims at the top, bottom, and
side. When the straightedge rests evenly on both
halves of the coupling, the coupling is in horizontal
parallel alignment. If the coupling is misaligned,
use a feeler gauge between the coupling and the
straightedge to measure the amount of misalign
ment.
V‐Belt Drives
When using V‐belt drives, the motor and the pump
must be parallel. Use a straightedge along the
sides of the pulleys to ensure that the pulleys are
properly aligned (see Figure B-4). In drive sys
tems using two or more belts, make certain that the
belts are a matched set; unmatched sets will cause
accelerated belt wear.

RP SERIES OM-06203
PAGE B - 7INSTALLATION
MISALIGNED:
SHAFTS
NOT PARALLEL
MISALIGNED:
SHAFTS
NOT IN LINE
ALIGNED: SHAFTS
PARALLEL AND
SHEAVES IN LINE
Figure B-4. Alignment of V‐Belt Driven Pumps
Tighten the belts in accordance with the belt manu
facturer's instructions. If the belts are too loose,
they will slip; if the belts are too tight, there will be
excessive power loss and possible bearing failure.
Select pulleys that will match the proper speed ra
tio; overspeeding the pump may damage both
pump and motor.
Do not operate the pump without a
guard in place over the rotating parts.
Exposed rotating parts can catch cloth
ing, fingers, or tools, causing severe in
jury to personnel.
V‐BELT TENSIONING
General Rules of Tensioning
For new V‐belts, check the tension after 5, 20 and
50 hours of operation and re‐tension as required
(see the following procedure for measuring belt
tension). Thereafter, check and re‐tension if re
quired monthly or at 500 hour intervals, whichever
comes first.
Ideal V‐belt tension is the lowest tension at which
the belt will not slip under peak load conditions. Do
not over‐tension V‐belts. Over‐tensioning will short
en both V‐belt and bearing life. Under‐tensioning
will cause belt slippage. Always keep belts free
from dirt, grease, oil and other foreign material
which may cause slippage.
Tension Measurement
Correct V‐belt tension can be achieved using a V‐
belt tension tester and Table B-2. Use the tables to
find the V‐belt size (cross‐section), the smallest
sheave diameter, the belt type for your application.
The corresponding deflection force required for
new or used belts is shown opposite the RPM
range of the pump.
Belt Span
Deflection
Figure B-5. Belt Tension Measurement
The ratio of deflection to belt span is 1:64 for both
ASA and metric units. Therefore, a belt with a span
of 64 inches would require a deflection of 1 inch at
the force shown on the Tables for your particular
application.
For example, if the span as measured in Figure
B-5 is 32 inches (813 mm), the v‐belt cross‐sec
tion is C, the smallest sheave diameter is 8 inches,
the pump speed is 1250 RPM, and the belts are un
cogged Hy‐T type, then 11.5 lbs. of force on the
tensioner should show 1/2‐inch (12,7 mm) of
deflection.
A tension tester is available as an option from Gor
man‐Rupp (P/N 29513-001). Other tension test
ers are available from your local belt/sheave dis
tributor, and work on a similar principal.
To use the Gorman‐Rupp tensioner, measure the
belt span as shown in Figure B-5. Position the bot
tom of the large O‐ring on the span scale of the ten
sioner at the measured belt span. Set the small O‐
ring on the deflection force scale to zero.
Place the tension tester squarely on the belt at the
center of the belt span. Apply force on the plunger,

OM-06203 RP SERIES
PAGE B - 8 INSTALLATION
perpendicular to the belt span, until the bottom of
the large O‐ring is even with the top of the next belt,
or with the bottom of a straight edge laid across the
sheaves.
Read the force applied from the bottom of the small
O‐ring on the deflection force scale. Compare this
force with the value shown in Table B- 2 and adjust
the tension accordingly. Note that the tension for
new belts is higher than that for used belts to al
low for expected belt stretching. Do not over‐ten
sion used belts to the higher deflection forces
shown for new belts.
Table B-2. Belt Deflection
Cross
Section
Smallest
Sheave
Diameter
Range
R.P.M.
Range
Used
Belt
New
Belt
Used
Belt
New
Belt
Belt Deflection Force
Uncogged
Hy‐T Belts &
Uncogged
Hy‐T Torque
Team
Cogged
Torque‐Flex
& Machined
Edge torque
Team Belts
A,AX
3.0 ‐ 3.6 1000‐2500
2501‐4000
3.7
2.8
5.5
4.2
4.1
3.4
6.1
5.0
3.8 ‐ 4.8 1000‐2500
2501‐4000
4.5
3.8
6.8
5.7
5.0
4.3 7.4
6.4
5.0 ‐ 7.0 1000‐2500
2501‐4000
5.4
4.7
8.0
7.0
5.7
5.1
9.4
7.4
B,BX
3.4 ‐ 4.2 860‐2500
2501‐4000
4.9
4.2
7.2
6.2
4.4 ‐ 5.6 860‐2500
2501‐4000
5.3
4.5
7.9
6.7
7.1
7.1
10.5
9.1
5.8 ‐ 8.6 860‐2500
2501‐4000
6.3
6.0
9.4
8.9
8.5
7.3
12.6
10.9
C,CX
7.0 ‐ 9.0 500‐1740
1741‐3000
11.5
9.4
17.0
13.8
14.7
11.9
21.8
17.5
9.5 ‐ 16.0 500‐1740
1741‐3000
14.1
12.5
21.0
18.5
15.9
14.6
23.5
21.6
D
12.0 ‐ 16.0 200‐850
851‐1500
11.5
9.4
17.0
13.8
14.7
11.9
21.8
17.5
18.0 ‐ 20.0 200‐850
851‐1500
30.4
25.6
45.2
38.0
3V,
3VX
2.2 ‐ 2.4 1000‐2500
2501‐4000
3.3
2.9
4.9
4.3
2.65 ‐ 3.65 1000‐2500
2501‐4000
3.6
3.0
5.1
4.4
4.2
3.8
6.2
5.6
4.12 ‐ 6.90 1000‐2500
2501‐4000
4.9
4.4
7.3
6.6
5.3
4.9
7.9
7.3
5V,
5VX
4.4 ‐ 6.7
500‐1749
1750‐3000
3001‐4000
10.2
8.8
5.6
15.2
13.2
8.5
7.1 ‐ 10.9 500‐1740
1741‐3000
12.7
11.2
18.9
16.7
14.8
13.7
22.1
20.1
11.8 ‐ 16.0 500‐1740
1741‐3000
15.5
14.6
23.4
21.8
17.1
16.8
25.5
25.0
8V
12.5 ‐ 17.0 200‐850
851‐1500
33.0
26.8
49.3
39.9
200‐850
851‐1500
39.6
35.3
59.2
52.7
18.0 ‐ 22.4
Cross
Section
Smallest
Sheave
Diameter
Range
R.P.M.
Range
Used
Belt
New
Belt
Used
Belt
New
Belt
Belt Deflection Force
Uncogged
Hy‐T Belts &
Uncogged
Hy‐T Torque
Team
Cogged
Torque‐Flex
& Machined
Edge torque
Team Belts
A,AX
75 ‐ 90 1000‐2500
2501‐4000
1.7
1.3
2.5
1.9
1.9
1.5
2.8
2.3
91 ‐ 120 1000‐2500
2501‐4000
2.0
1.7
3.1
2.6
2.3
2.0 3.4
2.9
125 ‐ 175 1000‐2500
2501‐4000
2.4
2.1
3.6
3.2
2.6
2.3
4.3
3.4
B,BX
85 ‐ 105 860‐2500
2501‐4000
2.2
1.9
3.3
2.8
106 ‐ 140 860‐2500
2501‐4000
2.4
2.0
3.6
3.0
3.2
3.2
4.8
4.1
141 ‐ 220 860‐2500
2501‐4000
2.9
2.7
4.3
4.0
3.9
3.3
5.7
4.9
C,CX
175 ‐ 230 500‐1740
1741‐3000
5.2
4.3
7.7
6.3
6.7
5.4
9.9
7.9
231 ‐ 400 500‐1740
1741‐3000
6.4
5.7
9.5
8.4
7.2
6.6
10.7
9.8
D
305 ‐ 400 200‐850
851‐1500
11.3
9.6
16.8
14.2
401 ‐ 510 200‐850
851‐1500
13.8
11.6
20.5
17.2
3V,
3VX
55 ‐ 60 1000‐2500
2501‐4000
1.5
1.3
2.2
2.0
61 ‐ 90 1000‐2500
2501‐4000
1.6
1.4
2.3
2.0
1.9
1.7
2.8
2.5
91 ‐ 175 1000‐2500
2501‐4000
2.2
2.0
3.3
3.0
2.4
2.2
3.6
3.3
5V,
5VX
110 ‐ 170
500‐1749
1750‐3000
3001‐4000
4.6
4.0
2.5
6.9
6.0
3.9
171 ‐ 1275 500‐1740
1741‐3000
5.8
5.1
8.6
7.6
6.7
6.2
10.0
9.1
276 ‐ 400 500‐1740
1741‐3000
7.0
6.6
10.6
9.9
7.8
7.6
11.6
11.3
8V
315 ‐ 430 200‐850
851‐1500
15.0
12.2
22.4
18.1
200‐850
851‐1500
18.0
16.0
26.8
23.9
431 ‐ 570
Sheave Dia. (Inches) Deflection Force (Lbs.) Sheave Dia. (MM) Deflection Force (Kg.)