GORMAN-RUPP PA Series User manual

OM-06768-01
September 10, 2015
GORMAN‐RUPP PUMPS
www.grpumps.com
2015 Gorman‐Rupp Pumps Printed in U.S.A.
INSTALLATION, OPERATION,
AND MAINTENANCE MANUAL
WITH PARTS LIST
PA SERIESPUMP
MODEL
PA6D60C‐B‐E50 460/3

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....................................
Pump Dimensions PAGE B - 1.....................................................
PREINSTALLATION INSPECTION PAGE B - 2............................................
POSITIONING PUMP PAGE B - 2.......................................................
Lifting PAGE B - 2.................................................................
Mounting PAGE B - 2.............................................................
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 - 3...............................................................
Strainers PAGE B - 3..............................................................
Sealing PAGE B - 3...............................................................
Suction Lines In Sumps PAGE B - 3.................................................
Suction Line Positioning PAGE B - 4................................................
DISCHARGE LINES PAGE B - 5........................................................
Siphoning PAGE B - 5.............................................................
Valves PAGE B - 5................................................................
ELECTRICAL CONNECTIONS PAGE B - 5...............................................
Grounding Methods PAGE B - 5....................................................
Field Wiring Connections (Incoming Power) PAGE B - 6...............................
Voltage Imbalance PAGE B - 6.....................................................
Power Cable Connections PAGE B - 6...............................................
ALIGNMENT PAGE B - 7..............................................................
AUTO‐START PAGE B - 7.............................................................
Float Switch Installation PAGE B - 7.................................................
COLD WEATHER INSTALLATION PAGE B - 8............................................
OPERATION - SECTION C PAGE C - 1......................................
STARTING AND OPERATION PAGE C - 1...............................................
Rotation PAGE C - 1..............................................................
Control Box Function PAGE C - 1...................................................
Priming PAGE C - 2...............................................................
Leakage PAGE C - 2..............................................................
Pump Vacuum Check PAGE C - 2..................................................
Priming Chamber Discharge Line PAGE C - 2........................................
Liquid Temperature And Overheating PAGE C - 2.....................................
Strainer Check PAGE C - 2.........................................................
STOPPING PAGE C - 3................................................................
Manual Stopping PAGE C - 3.......................................................

TABLE OF CONTENTS
(continued)
ii
Automatic Stopping PAGE C - 3....................................................
PERIODIC CHECKS PAGE C - 3.......................................................
Seal Cavity and Bearing Lubrication PAGE C - 3......................................
Bearing Temperature Check PAGE C - 3.............................................
COLD WEATHER PRESERVATION PAGE C - 3...........................................
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 Model PAGE E - 3..........................................................
Pump End Assembly PAGE E - 5...................................................
Pump Sub Assembly PAGE E - 7...................................................
Repair Rotating Assembly PAGE E - 9...............................................
Priming Chamber Kit PAGE E - 10...................................................
Priming Chamber Assembly PAGE E - 11.............................................
Air Compressor Assembly PAGE E - 12...............................................
PUMP AND SEAL DISASSEMBLY AND REASSEMBLY PAGE E - 13.........................
Priming Chamber Removal and Disassembly PAGE C - 14..............................
Discharge Check Valve Removal and Disassembly PAGE C - 14.........................
Suction Spool and Wear Plate Removal PAGE C - 14...................................
Draining Oil From Seal Cavity PAGE C - 15............................................
Separating Pump End From Power Source PAGE C - 15................................
Loosening Impeller PAGE C - 15.....................................................
Pump Casing Removal PAGE C - 16.................................................
Impeller Removal PAGE C - 16......................................................
Seal Removal PAGE C - 16..........................................................
Shaft and Bearing Removal and Disassembly PAGE C - 16.............................
Shaft and Bearing Reassembly and Installation PAGE C - 17............................
Seal Reassembly and Installation PAGE C - 18........................................
Impeller Installation And Adjustment PAGE C - 20......................................
Pump Casing Installation PAGE C - 20................................................
Securing Pump End To Power Source PAGE C - 20....................................
Suction Spool and Wear Plate Installation And Adjustment PAGE C - 21..................
Discharge Check Valve Reassembly And Installation PAGE C - 22.......................
Priming Chamber Assembly And Installation PAGE C - 22...............................
LUBRICATION PAGE C - 23.............................................................
Seal Assembly PAGE C - 23.........................................................
Bearings PAGE C - 23..............................................................

PA SERIES OM-06768
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.

PA SERIES OM-06768
PAGE A - 1SAFETY
SAFETY ‐ SECTION A
This information applies to Prime Airr
Series pumps. Refer to the manual ac
companying the power source before
attempting to begin operation.
This manual will alert personnel to
known procedures which require spe
cial attention, to those which could
damage equipment, and to those which
could be dangerous to personnel. How
ever, this manual cannot possibly antici
pate and provide detailed instructions
and precautions for every situation that
might occur during maintenance of the
unit. Therefore, it is the responsibility of
the owner/maintenance personnel to
ensure that only safe, established main
tenance procedures are used, and that
any procedures not addressed in this
manual are performed only after estab
lishing that neither personal safety nor
pump integrity are compromised by
such practices.
Before attempting to install, operate, or
wire the pump control box, familiarize
yourself with this manual, and with all
other literature shipped with the control
box. Unfamiliarity with all aspects of
control operation covered in this manu
al could lead to destruction of equip
ment, injury, or death to personnel.
Before connecting any cable to the con
trol box, be sure to ground the control
box. See Section B for suggested
grounding methods.
The control box provides overload pro
tection and power control. Do not con
nect the pump motor directly to the in
coming power lines. If the power circuit
breaker or overload relay is tripped dur
ing operation, correct the problem be
fore resetting or replacing.
The electrical power used to operate the
pump control box is high enough to
cause injury or death. Obtain the ser
vices of a qualified electrician to make
all electrical connections. Make certain
that the enclosure is properly
grounded; never use gas pipe as an
electrical ground. Be sure that the in
coming power matches the voltage and
phase of the control before connecting
the power source. Do not make electri
cal connections if the voltage is not
within the limits. If the overload unit is
tripped during operation, correct the
problem before restarting.
The electrical power used to operate the
pump control box is high enough to
cause injury or death. Make certain that
the control handle on the control box is
in the OFF position and locked out be
fore attempting to service the pump. Be
fore attempting to open or service the
control box, disconnect and/or lock out
the power supply to the control box. Tag
electrical circuits to prevent accidental
start‐up.

PA SERIESOM-06768
PAGE A - 2 SAFETY
Obtain the services of a qualified elec
trician to troubleshoot, test and/or ser
vice the electrical components of the
control box.
Before attempting to open or service the
pump:
1. Familiarize yourself with this man
ual.
2. Turn the control box selector
switch to `OFF' and lock it out to en
sure that the pump will remain in
operative.
3. Allow the pump to completely cool
if overheated.
4. Check the temperature before
opening 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 equipped with an automat
ic starting system, and therefore sub
ject to automatic restart. Keep hands
and clothing away from the unit to pre
vent injury during automatic operation.
Lock out the power from the control box
to ensure that the pump will remain in
operative. Failure to do so may result in
serious personal injury.
Do not attempt to disengage any part of
an overheated pump unit. Vapor pres
sure within the pump casing can eject
these parts with great force when they
are disengaged. Allow the pump to
completely cool before servicing it.
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.
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.
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

PA SERIES OM-06768
PAGE A - 3SAFETY
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,
pipe plugs, or fittings from an overheat
ed 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 guards
in place over the rotating parts. Ex
posed rotating parts can catch clothing,
fingers or tools, causing severe injury to
personnel.
Pumps and related equipment must be in
stalled and operated according to all na
tional, local and industry standards.
Make sure the pump is level. Lower jack
stands and chock the wheels, if so
equipped.

PA SERIES OM-06768
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.
Pump Dimensions
See Figure 1 for the approximate physical dimen
sions of this pump.
OUTLINE DRAWING
Figure 1. Pump Model PA6D60C-B-E50 460/3

OM-06768 PA SERIES
PAGE B - 2 INSTALLATION
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. Compare the amperes, phase, voltage and
hertz indicated on the pump motor nameplate
to the ratings indicated for the control box.
d. 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.
Only operate this pump in the direction in
dicated by the arrow on the pump body
and on the accompanying decal. Other
wise, the impeller could become loosened
from the shaft and seriously damage the
pump.
e. Check levels and lubricate as necessary. Re
fer to LUBRICATION in the Maintenance and
Repair Manual and perform duties as in
structed.
f. If the pump has been stored for more than 12
months, some of the components or lubri
cants may have exceeded their maximum
shelf life. These must be inspected or re
placed to ensure maximum 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.
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.
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.
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 or to eliminate vibra
tion.
If the pump has been mounted on a
movable 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.

PA SERIES OM-06768
PAGE B - 3INSTALLATION
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
The pump is drilled and tapped for installing dis
charge pressure and vacuum suction gauges. It is
recommended that gauges be installed to monitor
pump performance. Seal the gauge threads with
pipe dope to ensure an airtight seal. Follow the
sealant manufacturer's recommendations when
selecting and applying the pipe dope. The pipe
dope should be compatible with the liquid being
pumped.
SUCTION LINES
To avoid air pockets which could affect pump prim
ing, the suction line must be as short and direct as
possible. When operation involves a suction lift, the
line must always slope upward to the pump from
the source of the liquid being pumped; if the line
slopes down to the pump at any point along the
suction run, air pockets will be created.
Fittings
Suction lines should be the same size as the pump
inlet. If reducers are used in suction lines, they
should be the eccentric type, and should be 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.
This pump is designed to handle up to 3 inch (76,2
mm) diameter spherical solids.
Sealing
Since even a slight leak will affect priming, head,
and capacity, especially when operating with a
high suction lift, all connections in the suction line
should be sealed with pipe dope to ensure an air
tight seal. Follow the sealant manufacturer's 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

OM-06768 PA SERIES
PAGE B - 4 INSTALLATION
sump at a distance equal to 1 1/2 times the diame
ter 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 diameter
of the suction pipe. The baffle will allow entrained
air to escape from the liquid before it is drawn into
the suction inlet.
If two suction lines are installed in a single sump,
the flow paths may interact, reducing the efficiency
of one or both pumps. To avoid this, position the
suction inlets so that they are separated by a 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 2
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).
Figure 2. Recommended Minimum Suction Line Submergence vs. Velocity

PA SERIES OM-06768
PAGE B - 5INSTALLATION
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.
ELECTRICAL CONNECTIONS
Obtain the services of a qualified elec
trician to make all electrical connec
tions and to service the control box.
The electrical power used in this control
box is high enough to cause injury or
death. Make certain that the control box
is properly grounded after installation.
Make certain that the power source
phase and voltage matches the data on
the control box. Complete all electrical
connections before connecting the
power supply to the control box. Make
certain to ground the appropriate lead
of the power source before connecting
power to the control. Make certain that
the control box is properly grounded af
ter installation.
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 3 for some suggested ground
ing methods.

OM-06768 PA SERIES
PAGE B - 6 INSTALLATION
ROCK
8 FEET
(2,4 M)
3/4 INCH (19,1
MM) NOMINAL
DIAMETER
(MINIMUM)
SOIL
SOIL
SOIL
1/4 INCH STEEL
PLATE 2 SQ. FEET
(1858,1 SQ. CM)
SURFACE AREA
(MINIMUM)
a) PLATE ELECTRODE b) DRIVEN ELECTRODE c) BURIED ELECTRODE
3/4 INCH (19,1 MM)
NOMINAL DIAMETER
(MINIMUM) 8 FEET
(2,4 M) LONG
Figure 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).
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 m) from any other electrode or ground
rod, such as those used for signal circuits, ra
dio 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 ar
eas, pour water around the rod, or consult
qualified personnel to devise a method of im
proving the connection.
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 qu
alified electrician to make all electrical
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.
The control is designed to regulate the power sup
ply. The field wiring must be properly sized to en
sure an adequate voltage supply. The voltage
available at the pump motor must be within the in
dicated range.
Table 1. Pump Motor Voltage Limits
Nominal
Voltage
Minimum
Voltage
Maximum
Voltage
Phase
460 3 414 506
575 3 517 632
If the voltage is not within the recommended limits,
obtain the services of a qualified electrician to de
termine the correct field wiring size and other de
tails to ensure an adequate voltage supply.
Make certain all connections are tight and that ca
ble entry points are rainproof. Support the cable
weight, if required, to prevent excessive strain on
cable clamps and cable.
NOTE
After the power cables have been connected to the
control box, make certain the connection is water
proof.
Voltage Imbalance
Each phase of the incoming three‐phase power
must be balanced with the other two as accurately
as a commercial voltmeter will read. If the phases

PA SERIES OM-06768
PAGE B - 7INSTALLATION
are out of balance, contact your power company
and request that they correct the condition.
Power Cable Connections
The electrical power used to operate the
control box is high enough to cause in
jury 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.
When necessary to change or connect power
cables to the control box, make certain the incom
ing power is OFF and LOCKED OUT. Make certain
the control box is properly grounded and that the
electrical data on the control matches the pump
motor name plate data.
Connect the power cable to the control box as
shown in the wiring diagrams in this section or in
side the control box door. Use conduit or cable
clamps to secure the power and accessory cables
to the control box. Make certain that all connec
tions are tight and that cable entry points are
rainproof.
ALIGNMENT
The alignment of the pump and motor is critical for
trouble‐free mechanical operation. In a flexible
coupling system, the driver and pump must be
mounted so that their shafts are aligned with and
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, driver
and pump are aligned before shipment. Misalign
ment 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 driver mounting bolts should also be tightly
secured.
When checking alignment, disconnect
the power source to ensure that the
pump will remain inoperative.
Adjusting the alignment in one direction
may alter the alignment in another direc
tion. Check each procedure after altering
alignment.
AUTO‐START
The pump is equipped with an auto‐start control
system which allows the pump to start and stop as
the liquid level in the wet well or sump rises and
falls.
Refer to the information which follows for installa
tion details for the optional liquid level sensing sys
tem.
Float Switch Installation
The Float Switch autostart system employs either a
single or double float switch, where a bulb raises or
lowers (floats) with the liquid level, thus activating
an enclosed miniature switch. The floats are
equipped with a socket type connector that plugs
into a matching receptacle on the auto‐start control
box.
Standard floats are equipped with 50 feet (15,2 m)
of cable.
When installing the floats, note the following:
a. Be sure to provide sufficient room in the wet
well or sump so that floats do not get ob
structed or drawn into the suction line. If a flex
ible suction hose is used, it may be extended

OM-06768 PA SERIES
PAGE B - 8 INSTALLATION
to lay along the bottom of the wet well or sump
and the float can be attached to the hose
above the point where it bends along the bot
tom. Direct the suction line toward the flow,
and the float(s) away from the flow. If a stand
pipe is available, attach the float switch cable
to the standpipe in the sump at the approxi
mate desired liquid level.
b. In a single float system, the cable can be teth
ered to the suction line or standpipe approxi
mately 6 inches (152 mm) above the float.
This setting allows approximately 9 inches
(229 mm) of liquid rise between pump start/
stop. The start/stop interval may be increased
by extending the float end of the cable. The
liquid level in the sump will increase approxi
mately 8 inches (203 mm) between start/stop
intervals for every 6 inches (152 mm) of cable
increase.
c. If a double float switch system is used, posi
tion the “Start” float at the desired high water
level in the sump, and the “Stop” float at the
desired low water level in the pump.
d. Refer to Figure 4 for additional float switch
data.
OPERATING
RANGE
(See Table Below)
CABLE
TETHER
POINT
OFF
(Emptying)
ON
(Filling)
ON
(Emptying)
OFF
(Filling)
1.25” Pipe
(Not Furnished)
PUMP
CONTROL
BOX
1.0
(0.3)
APPROXIMATE FREE CORD LENGTH IN FT. (M)
0.5
(.15)
1.0
(0.3)
1.5
(.46)
2.0
(0.6)
2.5
(.76)
3.0
(0.9)
2.0
(0.6)
3.0
(0.9)
4.0
(1.2)
Figure 4. Float Switch Data
COLD WEATHER INSTALLATION
If the pump is to be installed in an environment
where sub‐freezing temperatures will occur during
operation, consideration must be given to prevent
the pump and components from freezing when the
pump is idle between pumping cycles. With Gor
man‐Rupp priming assisted pumps, there are two
methods of accomplishing this.
One method is through the use of an optional heat
ed priming chamber, which is available as a facto
ry‐installed option or as a retrofit kit. This method
pumps heated liquid from the engine cooling sys
tem through the priming chamber to heat the
chamber and its contents. This method is particu
larly effective where pumping cycles are short
enough to ensure that the liquid in the priming
chamber never fully freezes.
The second method involves configuring the
pumping system to drain both the priming cham
ber and pump casing after each pumping cycle.
With no liquid remaining in the system, freezing
cannot occur.
To configure the pump to drain between pumping
cycles, the first step is to remove the check valve
from the line that runs between the top of the prim
ing hopper and the priming venturi. This check
valve is located close to the venturi end of the line.
Remove the check valve, then reconnect the line
directly to the venturi. This will allow air to enter the
pump through the top of the priming hopper when
the pump shuts off, providing for complete
drainage of the pump and priming hopper.
Next, install a drain line between the pump drain
and the wet well or sump. This line must remain
submerged in the liquid below the pump down lev

PA SERIES OM-06768
PAGE B - 9INSTALLATION
el of the liquid level control device; otherwise, the
pump may not prime. If the application involves liq
uids that could clog the drain line, make sure to
check the line periodically to ensure it remains
open; otherwise, liquid could remain in the casing,
resulting in freezing and potential damage to the
pumping system.
Configuring the system to drain between cycles
will help ensure that the pump will not freeze during
cold weather applications. However, it should be
noted that the time required for the pump to be
gin to discharge liquid will increase, as the
pump will have to fully re‐prime at the beginning
of each pumping cycle.

OM-06768
PA SERIES
OPERATION PAGE C - 1
OPERATION - SECTION C
Review all SAFETY information in Section A.
Follow the instructions on all tags, labels and
decals attached to the pump.
The electrical power used to operate
this control box is high enough to cause
injury or death. Make certain that the
control 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
control box. Tag electrical circuits to
prevent accidental start‐up.
Obtain the services of a qualified elec
trician to make all electrical connec
tions, and to troubleshoot, test and/or
service the electrical components of the
control box.
This pump is designed to handle most
non‐volatile, non‐flammable liquids
containing specified entrained solids
and corrosives. Do not attempt to pump
volatile, corrosive, or flammable liquids
which may damage the pump or endan
ger personnel as a result of pump fail
ure.
STARTING AND OPERATION
Rotation
The correct direction of pump rotation is indicated
by an arrow on the pump body or accompanying
decals. If the pump is operated in the wrong direc
tion, the impeller could become loosened from the
shaft and seriously damage the pump.
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.
Disconnect the pump from the motor before
checking motor rotation. To check rotation, oper
ate the motor independently while observing the
direction of the motor shaft or cooling fan.
If rotation is incorrect, have a qualified electrician
interchange any two of the three phase wires at the
line connection to change direction.
Control Box Function
The control box provides overload pro
tection and power control. Do not con
nect the pump motor directly to the in
coming power lines.
The 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 also con
tains low voltage circuits for the automatic liquid
level sensing device(s).
The motor used to power this pump is controlled
by a Variable Frequency Drive (VFD), which can be
adjusted to control the performance of the pump
based on the requirements of the specific applica

OM-06768 PA SERIES
OPERATIONPAGE C - 2
tion. The VFD is programmed from the factory to
operate the pump within the maximum and mini
mum speed range shown on the Performance
Curve in Section E.
The selector switch controls the mode of opera
tion. In the OFF position, it prevents all operation of
the pump. In the ON position, it allows the pump to
run continuously. When used in conjunction with
liquid level controls, the AUTO position allows the
pump to be controlled automatically by the liquid
level control system.
Turn the selector switch to the desired setting (ON/
AUTO) and follow the instructions provided with
the Variable Frequency Drive Control Unit to start
and stop the unit and to set the motor speed for the
desired pump performance.
Priming
The pump will begin to prime upon startup. The air
in the suction line will be discharged from the prim
ing chamber discharge line. Complete priming is
indicated by a positive discharge pressure read
ing.
If full priming is not achieved, the discharge check
valve may be malfunctioning. If this occurs, shut
down the pump and consult the separate Mainte
nance and Repair manual for further details.
Leakage
Once the pump is fully primed, no leakage should
be visible at pump mating surfaces, or at pump
connections or fittings. Keep all line connections
and fittings tight to maintain maximum pump effi
ciency.
Pump Vacuum Check
Read the vacuum gauge with the pump primed
and at operation speed. Shut off the pump. The
vacuum gauge reading will immediately drop pro
portionate to static suction lift, and should then sta
bilize. If the vacuum reading falls off rapidly after
stabilization, an air leak exists. Before checking for
the source of the leak, check the point of installa
tion of the vacuum gauge.
Priming Chamber Discharge Line
Check the priming chamber discharge line for liq
uid bypass. If bypass occurs, shut down the pump.
Refer to the Maintenance and Repair Manual, dis
assemble and clean the float and valve assembly
inside the priming chamber.
Liquid Temperature and Overheating
Overheating can occur if operated with valves in
the suction or discharge lines closed. Operating
against closed valves could bring the liquid to a
boil, build pressure, and cause the pump to rup
ture or explode. If overheating occurs, stop the
pump immediately and allow it to completely cool
before servicing it. Approach any over‐heated
pump cautiously.
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.
Strainer Check
Check the strainer regularly and clean it as neces
sary. The strainer should also be checked if pump
flow rate begins to drop. Monitor and record the
vacuum suction gauge readings regularly to detect
strainer blockage.
Never introduce air or steam pressure into the
pump casing or piping to remove a blockage. This
could result in personal injury or damage to the
equipment. If backflushing is absolutely neces
sary, liquid pressure must be limited to 50% of the
maximum permissible operating pressure shown
on the pump performance curve.

OM-06768
PA SERIES
OPERATION PAGE C - 3
STOPPING
Manual Stopping
Turn the selector switch on the control box to the
OFF position.
After stopping the pump, lock out and tag out the
control box to ensure that the pump will remain in
operative.
Automatic Stopping
In the automatic mode, the pump will stop when
the liquid in the wet well or sump lowers and acti
vates the “Off” liquid level device(s). The pump will
restart automatically when the liquid rises and acti
vates the “On” liquid level device(s).
PERIODIC CHECKS
Seal And Bearing Cavity Lubrication
Both the seal and bearing cavities were fully lubri
cated at the factory. Check the lubrication levels
before startup and regularly thereafter as indicated
in the Maintenance and Repair Manual. When lu
brication is required, use only SAE No. 30 non‐det
ergent oil.
Bearing Temperature Check
Bearings normally run at higher than ambient tem
peratures because of heat generated by friction.
Temperatures up to 160F (71C) are considered
normal for bearings, and they can operate safely to
at least 180F (82C).
Checking bearing temperatures by hand is inaccu
rate. Bearing temperatures can be measured ac
curately by placing a contact‐type thermometer
against the housing. Record this temperature for
future reference.
A sudden increase in bearing temperatures is a
warning that the bearings are at the point of failing
to operate properly. Make certain that the bearing
lubricant is of the proper viscosity and at the cor
rect level (see LUBRICATION in the Maintenance
and Repair Manual). Bearing overheating can also
be caused by shaft misalignment and/or excessive
vibration.
When pumps are first started, the bearings may
seem to run at temperatures above normal. Con
tinued operation should bring the temperatures
down to normal levels.
COLD WEATHER OPERATION
If the pump is to be installed in an environment
where sub‐freezing temperatures will occur during
operation, consideration must be given to prevent
the pump and components from freezing when the
pump is idle between pumping cycles. Refer to
COLD WEATHER INSTALLATION in Section B for
cold weather applications.