GORMAN-RUPP PUMPS 2D-E.50 3P Application guide

OM−01476−OM03
October 14, 1981
Rev. D 12-04-08
THE GORMAN-RUPP COMPANY DMANSFIELD, OHIO
www.grpumps.com
GORMAN-RUPP OF CANADA LIMITED DST. THOMAS, ONTARIO, CANADA Printed in U.S.A.
e1981 The Gorman-Rupp Company
INSTALLATION, OPERATION,
AND MAINTENANCE MANUAL
WITH PARTS LIST
D SERIES PUMP
MODEL
2D−E.50 3P

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 − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
POSITIONING PUMP PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lifting PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mounting PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SUCTION AND DISCHARGE PIPING PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Materials PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Line Configuration PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fixed, Rigid Piping PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gauges PAGE B − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SUCTION LINES PAGE B − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fittings PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strainers PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sealing PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DISCHARGE LINES PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Siphoning PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valves PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ELECTRICAL CONNECTIONS PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OPERATION − SECTION C PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
STARTING PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OPERATION PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Priming PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OPERATION CHECKS PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gearbox Check PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Leakage Check PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strainer Check PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
STOPPING PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cold Weather Preservation PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GEARBOX TEMPERATURE CHECK PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING − SECTION D PAGE D − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PUMP MAINTENANCE AND REPAIR - SECTION E PAGE E − 1. . . . . . . . . . . . . . . . . .
STANDARD PERFORMANCE CHART PAGE E − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PARTS LISTS:
Pump Model PAGE E − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Plunger Rod Assembly PAGE E − 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PUMP DISASSEMBLY AND REASSEMBLY PAGE E − 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Suction And Discharge Check Valve Removal PAGE E − 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diaphragm and Plunger Rod Removal PAGE E − 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TABLE OF CONTENTS
(continued)
ii
Plunger Rod and Diaphragm Removal PAGE E − 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Suction And Discharge Check Valve Installation PAGE E − 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LUBRICATION PAGE E − 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Plunger Rod Assembly PAGE E − 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gear Reducer PAGE E − 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

D SERIES OM−01477
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 Maintenance
manual is designed to help you achieve the best
performance and longest life from your Gorman-
Rupp pump.
This is a D Series, positive displacement pump,
utilizing a single-action diaphragm to produce a
straight-through flow of liquid. The pump is flex-
coupled to a 1/2 HP electric motor. It is ideally
suited to industrial and contractor’s applications
since it will handle liquids ranging from clear water
to construction-site muck. The basic material of
construction for wetted parts is aluminum, with
neoprene flap valves and diaphragm.
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
P.O. Box 1217
Mansfield, Ohio 44901−1217
Phone: (419) 755−1011
or:
Gorman-Rupp of Canada Limited
70 Burwell Road
St. Thomas, Ontario N5P 3R7
Phone: (519) 631−2870
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.

D SERIES OM−01477
PAGE A − 1SAFETY
SAFETY - SECTION A
This information applies to D Series
electric motor driven diaphragm
pumps. Refer to the manual accompa-
nying the motor before attempting to
begin operation.
Before attempting to open or service the
pump:
1. Familiarize yourself with this man-
ual.
2. Lock out and tag out incoming
power to the motor to ensure that
the pump will remain inoperative.
3. Allow the pump to completely cool
if overheated.
4. Drain the pump.
This pump is designed to handle non-
volatile non-flammable liquids contain-
ing specified entrained solids. Do not
attempt to pump volatile, corrosive, or
flammable liquids which may damage
the pump or endanger personnel as a
result of pump failure.
After the pump has been installed, block
the wheels and secure the pump to pre-
vent creeping. Make certain that the
pump and all piping or hose connec-
tions are tight, properly supported and
secure before operation.
All electrical connections must be in ac-
cordance with the National Electric
Code. If there is a conflict between in-
structions provided and N.E.C. specifi-
cations, 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.
Do not operate the pump without the ec-
centric and coupling guards in place
over the rotating parts. Exposed rotat-
ing parts can catch clothing, fingers, or
tools, causing severe injury to person-
nel.
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 the pump
and motor are properly grounded; never
use gas pipe as an electrical ground. Be
sure that the incoming power matches
the voltage and phase of the motor be-
fore making motor connections. Do not
run the pump if the voltage is not within
limits.

D SERIESOM−01477
PAGE A − 2 SAFETY
Do not install and operate a non-explo-
sion proof motor in an explosive atmo-
sphere. Install, connect, and operate
the motor in accordance with The Na-
tional Electric Code and all local codes.
If there is a conflict between the instruc-
tions in the manual accompanying the
unit and The National Electric Code or
the applicable local code, The National
or local code shall take precedence.
Never install a positive shut-off valve in the
discharge line; discharge restrictions will
cause excessive friction loss resulting in
overloading and destruction of pump and
drive components. It is strongly recom-
mended that unless absolutely necessary,
no positive shut-off valve be installed in the
suction line; excessive restriction will
cause incomplete filling of the diaphragm
chamber and result in shortened dia-
phragm life.

D SERIES OM−01477
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.
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 2D-E.50 3P
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.
d. Check levels and lubricate as necessary. Re-
move the shipping plug from the top of the
gear reducer and replace it with the vented
plug shipped loose with the unit. Refer to LU-
BRICATION in the MAINTENANCE AND RE-
PAIR section of this manual and perform du-
ties as instructed.
e. If the pump and motor have been stored for
more than 12 months, some of the compo-

OM−01477 D SERIES
PAGE B − 2 INSTALLATION
nents or lubricants may have exceeded their
maximum shelf life. These must be inspected
or replaced to ensure maximum pump serv-
ice.
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
Do not install and operate a non-explo-
sion proof motor in an explosive atmo-
sphere.
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 cables or chains 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 or to eliminate vibra-
tion.
After the pump has been positioned, block the
wheels and secure the pump to prevent creeping.
SUCTION AND DISCHARGE PIPING
Pump performance is adversely effected by in-
creased suction lift, discharge elevation, and fric-
tion losses. See Page E-1 to be sure your overall
application allows the 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.
Never pull a line into place by tightening connec-
tions at the pump. Lines near the pump must be in-
dependently supported to avoid strain on the
pump which could cause excessive vibration and
increased diaphragm and gear train wear. If hose-
type lines are used, they should have adequate
support to secure them when filled with liquid and
under pressure.
Fixed, Rigid Piping
This pump is equipped with an integral suction ac-
cumulator chamber which promotes an efficient
flow of liquid and acts as an air cushion against
shock. Since the air in this chamber will leak away

D SERIES OM−01477
PAGE B − 3INSTALLATION
during pump operation, the air must be replen-
ished periodically. To introduce air into the cham-
ber, stop the pump and remove the suction accu-
mulator plug and integral gasket; this will break
prime and allow the liquid in the chamber to drain
away through the suction line.
If the pump is mounted in a system with fixed, rigid
piping, it is recommended that a flexible connec-
tion be installed at or near the suction and dis-
charge ports to absorb shock which would other-
wise be transmitted through the drive train and
greatly accelerate pump wear.
In a fixed piping installation, properly sized surge
suppressors must be installed in both suction and
discharge lines. If commercial surge suppressors
are not readily available, air chambers may be fab-
ricated from pipe as shown in Figure 2.
AIR CHAMBERS
(18 TO 24 INCH LENGTHS OF
6 TO 8 INCH DIAMETER PIPE
WITH WELDED CAPS)
DISCHARGE
CHAMBER
DISCHARGE
FLEXIBLE JOINT FLEXIBLE JOINT
SUCTION
CHAMBER
1/2-INCH VALVE FOR
RECHARGING AIR
CHAMBER WITH
COMPRESSED AIR
(ALSO ON DISCHARGE
CHAMBER)
SUCTION
NOTE: INSTALL AIR CHAMBERS OFF FLOW LINE TEES
TO AVOID SURFACE TURBULENCE WITHIN CHAMBERS.
Figure 2. Fixed Piping Installation
Note that the air chambers have not been installed
directly in the flow line, but have been installed off
tees to avoid turbulence within the chambers. The
air chambers are fitted with valves to permit intro-
duction of small amounts of compressed air to fur-
ther dampen shock; this compressed air will leak
away during operation, and should be replaced
from time to time. If the suction chamber floods,
open the suction chamber valve to break prime
and allow the liquid in chamber to drain through
the suction line.
Gauges
If discharge pressure and vacuum suction gauges
are desired, 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
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.
NOTE
Maximum pump performance is realized at suction
lifts of 5 feet (1,5 m) or less. Use the shortest possi-

OM−01477 D SERIES
PAGE B − 4 INSTALLATION
ble length of suction hose or piping; lengths of 25
feet (7,6 m) or longer will reduce the capacity of the
pump.
It is strongly recommended that no positive shut-
off valve be installed in the suction line; excessive
restrictions will cause incomplete filling of the dia-
phragm chamber and result in short diaphragm
life.
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. The suction line
should not be restricted more than 1 inch below the
nominal suction size.
The use of pipe couplings in the suction line is not
recommended.
Strainers
If a strainer is furnished with the pump, be certain
to use it; any spherical solids which pass through a
strainer furnished with the pump will also pass
through the pump itself.
If a strainer is not furnished with the pump, but is
installed by the pump user, make certain that the
total area of the openings in the strainer is at least
three or four times the cross section of the suction
line, and that the openings will not permit passage
of solids larger than the solids handling capability
of the pump.
This pump is designed to handle up to 2-1/4 inch
(57,2 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.
DISCHARGE LINES
The discharge line must be the same size
as, or larger than, the suction line. Never in-
stall or operate the pump with a discharge
line smaller than the suction; a restricted
discharge line will cause excessive friction
loss resulting in overloading and destruc-
tion of pump and drive components.
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
The pump is provided with integral suction and dis-
charge check valves.
Never install a positive shut-off valve in the
discharge line; discharge restrictions will
cause excessive friction loss resulting in
overloading and destruction of pump and
drive components. It is strongly recom-
mended that unless absolutely necessary,
no positive shut-off valve be installed in the
suction line; excessive restriction will
cause incomplete filling of the diaphragm
chamber and result in shortened dia-
phragm life.
ELECTRICAL CONNECTIONS
Before connecting the motor to the incoming
power, check that the electrical service available

D SERIES OM−01477
PAGE B − 5INSTALLATION
matches the pump motor requirements stamped
on the motor nameplate.
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 the pump
and motor are properly grounded; never
use gas pipe as an electrical ground. Be
sure that the incoming power matches
the voltage and phase of the motor be-
fore making motor connections. Do not
run the pump if the voltage is not within
limits.
Do not install and operate a non-explo-
sion proof motor in an explosive atmo-
sphere. Install, connect, and operate
the motor in accordance with The Na-
tional Electric Code and all local codes.
If there is a conflict between the instruc-
tions in the manual accompanying the
unit and The National Electric Code or
the applicable local code, The National
or local code shall take precedence.
Refer to the following motor data before making
electrical connections.
Motor Data
VOLTAGE PHASE HP Hz RPM
230/460 3 .50 60 1725
MODEL
2D−E.50 3P

OM−01477
D 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.
This pump is designed to handle non-
volatile non-flammable liquids contain-
ing specified entrained solids. Do not
attempt to pump volatile, corrosive, or
flammable liquids which may damage
the pump or endanger personnel as a
result of pump failure.
After the pump has been installed, block
the wheels and secure the pump to pre-
vent creeping. Make certain that the
pump and all piping or hose connec-
tions are tight, properly supported and
secure before operation.
Pump application will affect its performance, espe-
cially discharge velocities. Consult the Gorman-
Rupp factory for actual performance levels for the
pump.
Install the pump and piping as described in IN-
STALLATION. Make sure that the piping connec-
tions are tight, and that the pump is securely
mounted. Check that components are properly lu-
bricated (see LUBRICATION in MAINTENANCE
AND REPAIR).
Make certain that any positive shut-off
valve installed in the suction line is open
before operating the pump; excessive re-
striction will cause incomplete filling of the
diaphragm chamber and result in short-
ened diaphragm life. No positive shut-off
valve should be installed in the discharge
line.
STARTING
Consult the operations manual furnished with the
motor before starting the pump.Open any valves
installed in the suction line and start the pump.
OPERATION
Priming
The pump may not prime immediately because the
suction line must first fill with liquid. If the pump fails
to prime within five minutes, stop the engine and
check the suction line for leaks.
OPERATION CHECKS
Gearbox Check
Check that the gearbox is properly lubricated (see
LUBRICATION in MAINTENANCE AND RE-
PAIR).
Leakage Check
No leakage should be visible at pump mating sur-
faces, connections or fittings. Keep all line connec-
tions and fittings tight to maintain maximum pump
efficiency.
Strainer Check
If a suction strainer has been installed, check and
clean it as necessary. It should be cleaned if pump
flow begins to drop. If a vacuum suction gauge has
been installed, monitor and record the readings
regularly to detect strainer blockage.

OM−01477 D SERIES
OPERATIONPAGE C − 2
STOPPING
After stopping the pump, lock out and tag out in-
coming power to the motor to ensure that the
pump will remain inoperative.
If the pump will be idle for more than a few hours, or
if it has been pumping liquids containing a large
amount of solids, flush it with clean water.
Cold Weather Preservation
The primary construction materials of this
pump are aluminum, with neoprene flap
valves and diaphragm. Do not attempt to
clean or flush this pump with any liquid
which would attack pump fittings or com-
ponents. Avoid cleaning with cleaning sol-
vent.
In below freezing conditions, drain the water from
the pump and the lines when the pump is not in op-
eration. Also, clean out any solids by flushing with a
hose.
GEARBOX TEMPERATURE CHECK
The gearbox runs higher than ambient tempera-
tures because of heat generated by friction. Tem-
peratures of approximately 200_F (93_C) are con-
sidered normal, and can operate intermittently at
250_F (121_C).
Checking gearbox temperatures by hand is inac-
curate. Place a contact-type thermometer against
the housing and record this temperature for future
reference.
A sudden increase in gearbox temperature is a
warning that the bearings are at the point of failing.
Make certain that the bearing lubricant is of the
proper viscosity and at the correct level (see LU-
BRICATION in Section E). 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.

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP FAILS TO
PRIME
PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE
D SERIES OM−01477
TROUBLESHOOTING PAGE D − 1
TROUBLESHOOTING − SECTION D
Review all SAFETY information in Section A.
Before attempting to open or service
the pump:
1. Familiarize yourself with this man-
ual.
2. Lock out and tag out incoming
power to ensure that the pump will
remain inoperative.
3. Allow the pump to completely cool
if overheated.
4. Drain the pump.
Air leak in suction line. Correct leak.
Lining of suction hose collapsed. Replace suction hose.
Integral suction or discharge check Clean valves, check that flange nuts
valve clogged, binding, or not seating are tight.
properly.
Cracked or broken diaphragm. Replace diaphragm.
Diaphragm not securely in place. Secure diaphragm.
Strainer clogged. Check strainer and clean if necessary.
Air leak in suction line. Correct leak.
Suction intake not properly submerged. Check installation.
Lining of suction hose collapsed. Replace suction hose.
Cracked or broken diaphragm. Replace diaphragm.
Diaphragm not securely in place. Secure diaphragm.
Strainer clogged. Check strainer and clean if necessary.
Integral suction or discharge check Clean valves, check that flange nuts
valve clogged, binding, or not seating are tight.
properly.

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP REQUIRES
TOO MUCH
POWER
PUMP CLOGS
FREQUENTLY
EXCESSIVE NOISE
BEARINGS RUN
TOO HOT
OM−01477 D SERIES
TROUBLESHOOTINGPAGE D − 2
Liquid solution too thick. Dilute if possible.
Integral discharge check valve clogged Clean valve.
or binding.
Bearings in motor or gearbox Check bearings.
worn or binding.
Integral suction or discharge check Clean valves, check that flange nuts
valve clogged, binding, or not seating are tight.
properly.
Liquid solution too thick. Dilute if possible.
Pump, gearbox, or motor not Check and tighten mounting bolts.
securely mounted.
Gearbox or motor not properly See LUBRICATION in MAINTE-
lubricated. NANCE AND REPAIR.
Bearing temperature is high, but within Check bearing temperature regularly
limits. to monitor any increase.
Low or incorrect lubricant. Check for proper type and level of
lubricant.
Drive misaligned. Align drive properly.

D SERIES OM−01477
MAINTENANCE & REPAIR PAGE E − 1
PUMP MAINTENANCE AND REPAIR - SECTION E
MAINTENANCE AND REPAIR OF THE WEARING PARTS OF THE PUMP WILL MAINTAIN PEAK
OPERATING PERFORMANCE.
IN GALLONS PER MINUTE AT 60 STROKES PER MINUTE
STATIC
LIFT
IN FEET
STATIC DISCHARGE HEAD IN FEET
510 15 20
5272624 22
2510 24 21 20
19202122
21 20
15
1920 18
20
19
18
17
0
IN LITERS PER MINUTE AT 60 STROKES PER MINUTE
STATIC
LIFT
IN METERS
STATIC DISCHARGE HEAD IN METERS
1,5 3,0 4,6 6,1
102,2 98,4 90,8 83,31,5
94,6 90,8 79,5 75,7
71,9
3,0
75,779,583,3
79,5 75,7 71,9 68,1
75,7
71,9
4,6 68,1
6,1 64,3
0
STANDARD PERFORMANCE TEST DATA FOR 2D ELECTRIC MOTOR DRIVEN PUMP
Based on 70_F (21_C) clear water at sea level
with minimum suction lift, using 2 inch (50 mm)
suction hose and 2 inch (50 mm) non-collapsible
discharge hose. Since pump installations are sel-
dom identical, your performance may be differ-
ence due to such factors as specific gravity, eleva-
tion and temperature.
If your pump serial number is followed by an N",
your pump is NOT a standard production model.
Contact the Gorman-Rupp Company to verify per-
formance or part numbers.

D SERIESOM−01477
MAINTENANCE & REPAIRPAGE E − 2
PARTS PAGE
SECTION DRAWING
Figure 1. 2D−E.50 3P Pump Model

ITEM
NO.
PART NAME PART
NUMBER
MAT’L
CODE
QTY ITEM
NO.
PART NAME PART
NUMBER
MAT’L
CODE
QTY
D SERIES OM−01477
MAINTENANCE & REPAIR PAGE E − 3
PARTS LIST
2D−E.50 3P Pump Model
(From S/N 661275 Up)
If your pump serial number is followed by an N", your pump is NOT a standard production model. Contact
the Gorman-Rupp Company to verify part numbers.
1 .50 HP 3P MOTOR 28211−540 −−− 1
2 HEX HD CAPSCREW B0604 15991 REF
3 LOCK WASHER J06 15991 REF
4 CARRY HANDLE 44724−007 24150 1
5 VENTED PLUG 4823 15079 1
6 SHIPPING PLUG 11495 15079 1
7 GEAR REDUCER 24572−003 −−− 1
8 ROTATION DECAL 2613BM −−− 1
9 LUBE DECAL 38816−085 −−− 1
10 PLUNGER ROD ASSY 46181−004 −−− 1
11 RETAINING RING 26812−702 −−− 1
12 KEY N0403 15990 1
13 ECCENTRIC GUARD ASSY 42381−024 24150 1
14 HEX HD CAPSCREW B0605 15991 4
15 LOCK WASHER J06 15991 4
16 HEX NUT D06 15991 4
17 HEX HD CAPSCREW B0508 15991 4
18 HEX NUT D05 15991 4
19 HEX HD CAPSCREW B00503 15991 2
20 DISCHARGE FLANGE 26812−707 −−− 1
21 DISCHARGE VALVE ASSY 26812−708 −−− 1
22 HEX HD CAPSCREW B0505 15991 2
23 HEX NUT D05 15991 2
24 DIAPHRAGM POT 38234−006 10010 1
25 HEX HD CAPSCREW B0506 15991 4
26 LOCK WASHER J05 15991 4
27 HEX NUT D05 15991 4
28 SUCTION VALVE ASSY 26812−705 −−− 1
29 HEX HD CAPSCREW B0503 15991 4
30 SUCTION FLANGE 26812−704 −−− 1
31 SUCTION STICKER 6588AG −−− 1
32 TAP SCREW 21281−472 −−− 4
33 HEX HD CAPSCREW B0604 15991 4
34 LOCK WASHER J06 15991 4
35 HEX NUT D06 15991 4
36 NAME PLATE 38818−004 13990 1
37 DRIVE SCREW BM#04−03 15990 4
38 BASE ASSY 41547−017 24150 1
NOT SHOWN:
G-R DECAL GR−03 −−− 1
INSTRUCTION TAG 38817−030 −−− 1
STRAINER 9026D 24001 1
KEY N0303 15990 REF
WARNING DECAL 2613FE −−− 1
WARNING DECAL 2613FF −−− 1
DISCHARGE STICKER 6588BJ −−− 1
OPTIONAL:
WHEEL LKIT GRP30−41 −−− 1
INDICATES PARTS RECOMMENDED FOR STOCK

D SERIESOM−01477
MAINTENANCE & REPAIRPAGE E − 4
SECTION DRAWING
Figure 2. 46181−004 Plunger Rod Assembly