GORMAN-RUPP PUMPS 0 Series User manual

OM-06273-02
November 8, 2012
BCE
THE GORMAN‐RUPP COMPANY DMANSFIELD, OHIO
www.grpumps.com
GORMAN‐RUPP OF CANADA LIMITED DST. THOMAS, ONTARIO, CANADA Printed in U.S.A.
e2012 The Gorman‐Rupp Company
INSTALLATION, OPERATION,
AND MAINTENANCE MANUAL
WITH PARTS LIST
0 SERIES PUMP
MODEL
03H1-HYD

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....................................
PREINSTALLATION INSPECTION PAGE B - 1............................................
PUMP INSTALLATION PAGE B - 1......................................................
Pump Dimensions PAGE B - 1.....................................................
VEHICLE REQUIREMENTS PAGE B - 2.................................................
Tank Preparation PAGE B - 2.......................................................
POSITIONING PUMP PAGE B - 2.......................................................
Lifting PAGE B - 2.................................................................
Mounting PAGE B - 2.............................................................
Hydraulic Motor Connections 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 - 3...............................................................
Strainers PAGE B - 3..............................................................
Sealing PAGE B - 4...............................................................
DISCHARGE LINES PAGE B - 4........................................................
Siphoning PAGE B - 4.............................................................
Valves PAGE B - 4................................................................
Bypass Lines PAGE B - 4..........................................................
OPERATION - SECTION C PAGE C - 1......................................
INTRODUCTION TO PUMP OPERATION PAGE C - 1.....................................
PRIMING PAGE C - 1.................................................................
GROUNDING PAGE C - 2.............................................................
STARTING PAGE C - 2................................................................
Rotation PAGE C - 2..............................................................
OPERATION PAGE C - 2..............................................................
Operating Controls PAGE C - 2.....................................................
OPERATING CHECKS PAGE C - 2......................................................
Lines With a Bypass PAGE C - 2....................................................
Lines Without a Bypass PAGE C - 2.................................................
Leakage PAGE C - 3..............................................................
Strainer Check PAGE C - 3.........................................................
Liquid Temperature and Overheating PAGE C - 3.....................................
Pump Vacuum Check PAGE C - 3..................................................
STOPPING PAGE C - 4................................................................
Cold Weather Preservation PAGE C - 4..............................................
TROUBLESHOOTING - SECTION D PAGE D - 1..............................

TABLE OF CONTENTS
(continued)
ii
PUMP MAINTENANCE AND REPAIR ‐ SECTION E PAGE E - 1.................
PERFORMANCE CURVE PAGE E - 1...................................................
PARTS LIST:
Pump Model PAGE E - 5..........................................................
PUMP AND SEAL DISASSEMBLY AND REASSEMBLY PAGE E - 6.........................
Removing Pump and Hydraulic Motor PAGE E - 6....................................
Pump Casing and Wear Ring Removal PAGE E - 7....................................
Impeller Removal PAGE E - 7......................................................
Seal Removal and Disassembly PAGE E - 8..........................................
PUMP AND SEAL REASSEMBLY PAGE E - 8............................................
Seal Reassembly and Installation PAGE E - 8........................................
Impeller Installation PAGE E - 10.....................................................
Pump Casing and Wear Ring Installation PAGE E - 10..................................
Installing Pump and Hydraulic Motor PAGE E - 11.....................................
LUBRICATION PAGE E - 11.............................................................
Seal Assembly PAGE E - 11.........................................................

OM-062730 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 pump is an 0 Series, enclosed impeller, self‐
priming centrifugal model, with straight‐in suction
without a suction check valve. It is close‐coupled to
a hydraulic motor and designed for vehicular
mounting in petroleum or water service. The basic
material of construction for wetted parts is alumi
num, with bronze wear rings.
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]
No instructions are provided in this manual for hy
draulic motor maintenance. For information or
technical assistance on the hydraulic motor, con
tact the hydraulic motor manufacturer through
their website at www.parker.com and reference
the following hydraulic motor model:
Parker Model #PGM 020C894-BEEF07
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.

0 SERIES OM-06273
PAGE A - 1SAFETY
SAFETY ‐ SECTION A
This information applies to 0 Series
tanker pumps. Gorman‐Rupp has no
control over or particular knowledge of
the vehicle chassis which will be used.
Refer to the manual accompanying the
power source before attempting to be
gin operation.
Before attempting to open or service the
pump:
1. Familiarize yourself with this man
ual.
2. Switch off the vehicle ignition and
remove the key, or take other pre
cautions to ensure that the pump
will remain inoperative.
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 designed for vehicular
mounting in petroleum or water service.
Do not attempt to pump corrosive mate
rials, or any liquids which may damage
the pump or endanger personnel as a
result of pump failure.
Be certain proper safety practices are
followed before operating or servicing
the pump. When pumping petroleum
products, provide adequate ventilation,
prohibit smoking, wear static resistant
clothing and shoes. Clean up all fuel
spills immediately after occurrence.
Do not operate the pump against a
closed discharge valve for long periods
of time. If operated against a closed dis
charge valve, pump components will
deteriorate, and the liquid could come
to a boil, build pressure, and cause the
pump casing to rupture or explode.
Overheating may produce dangerous
fumes. Take precautions to ensure the
area surrounding the pump is ade
quately ventilated. Allow the pump to
cool and use extreme caution when
venting the pump, or when removing
covers, plates, plugs, or fittings.
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.

0 SERIESOM-06273
PAGE A - 2 SAFETY
Overheated pumps can cause severe
burns and injuries. If overheating of the
pump occurs:
1. Stop the pump immediately.
2. Ventilate the area.
3. Allow the pump to completely cool.
4. Check the temperature before
opening any covers, plates,
gauges, or plugs.
5. Vent the pump slowly and cau
tiously.
6. Refer to instructions in this manual
before restarting the pump.
After the vehicle is positioned for pump
maintenance, block the wheels and set
the emergency brake before attempting
to remove the pump. Be Sure the pump
is properly reinstalled and secure be
fore operation.
Never run the pump dry of pumping me
dium. There must be a supply of liquid to
the pump at all times to prevent destruction
of the shaft seal faces.

0 SERIES OM-06273
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 (see Sec
tion E, Page 1).
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 assembly for cracks, dents,
damaged threads, and other obvious dam
age.
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. If the pump and gearbox have been stored for
more than 12 months, some of the compo
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.
PUMP INSTALLATION
Pump Dimensions
See Figure 1 for the physical dimensions of the
pump.

OM-06273 0 SERIES
PAGE B - 2 INSTALLATION
Figure 1. Pump Model 03H1-HYD Dimensions
VEHICLE REQUIREMENTS
The following instructions apply equally to new in
stallations, rebuilds or retrofits.
Tank Preparation
It is essential that any tank scale, dirt, or other for
eign material be removed from the tank and piping
prior to pump installation. Failure to do so could re
sult in clogging or damage to the pump.
Damage to the pump resulting from debris
in the suction line will not be covered by
the pump warranty.
Before connecting the suction and dis
charge piping, carefully check the storage
tank and piping for construction debris
such as nuts, bolts, wire, weld slag, and
other foreign material. Install a commer
cially available 80 mesh screen in the suc
tion line to prevent debris from entering the
pump.
POSITIONING PUMP
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
Level mounting is essential for proper operation.
The pump may have to be supported or shimmed
to provide for level operation or to eliminate vibra
tion. The pump must be mounted on a rigid, vibra

0 SERIES OM-06273
PAGE B - 3INSTALLATION
tion‐free base or platform. The pump should be
placed directly over a beam or as near to a main
support as possible.
Any damage to the pump resulting from improper
mounting and installation is not covered by the
Gorman‐Rupp warranty.
When filling the tank, locate the pump in an acces
sible place as close as practical to the fuel being
pumped. Vertical distance (static suction lift)
should be kept to a minimum. High static lift and a
long suction line results in a longer period of time
required to prime the pump. They also tend to limit
the maximum amount of liquid pumped.
Hydraulic Motor Connections
Remove the plug in the top of the motor and install
a vent line back to the hydraulic tank in the plug
opening. Connect the hydraulic lines to the ap
propriate openings in the motor as indicated by the
decals on the motor. Pressurize the hydraulic sys
tem and check for leaks before putting the pump
into service.
SUCTION AND DISCHARGE PIPING
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
This pump has a 1/4‐inch NPT tap on the suction
side for installation of a vacuum suction gauge.
If a discharge pressure gauge is desired, drill and
tap the discharge line in a visible location approxi
mately three pipe diameters away from any fittings
or points of turbulent flow. 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.
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
A suction strainer was not furnished with this pump
since it is not designed to handle liquids containing
solids. However, to protect the pump from acciden
tal damage a commercially available 80 mesh
screen should be installed in the suction line. Make
certain that the total open area of the screen is at
least three or four times the cross section of the

OM-06273 0 SERIES
PAGE B - 4 INSTALLATION
suction line to ensure an adequate supply of liquid
to the pump.
Damage to the pump resulting from debris
in the suction line will not be covered by the
pump warranty.
Before connecting the suction and dis
charge piping, carefully check the storage
tank and piping for construction debris
such as nuts, bolts, wire, weld slag, and
other foreign material. Install a commer
cially available 80 mesh screen in the suc
tion line to prevent debris from entering the
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 to ensure an airtight seal. Follow
the sealant manufacturer's recommendations
when selecting and applying the sealant. The seal
ant should be compatible with the liquid being
pumped.
When pumping petroleum products, a
leak at any point in the system may ex
pel flammable vapor into the atmo
sphere. Be sure the pump and sur
rounding area are adequately venti
lated. Check all connections for leaks
and correct any problems immediately.
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
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.
A check valve in the discharge line is normally rec
ommended, but it is not necessary in low dis
charge head applications.
With high discharge heads, it is recommended that
a throttling valve and a system check valve be in
stalled in the discharge line to protect the pump
from excessive shock pressure and reverse rota
tion when it is stopped.
If the application involves a high discharge
head, gradually close the discharge
throttling valve before stopping the pump.
Bypass Lines
If it is necessary to permit the escape of air into at
mosphere in initial priming or during the repriming
cycle, install a bypass line ‐ sized to that it will not
affect pump discharge capacity ‐ between the
pump and the discharge check valve. Since the
pump does not use a suction check valve, the end
of the bypass line must be submerged in the liquid
being pumped in order to maintain suction.

OM-06273
0 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.
INTRODUCTION TO PUMP OPERATION
This pump is designed to produce 300 gallons per
minute and functions in the following manner.
During the priming cycle, air from the suction line
entering the pump is mixed with fuel at the impeller.
Centrifugal force moves the mixture into the pump
housing reservoir, where the velocity of the mixture
is decreased. Air escapes through the discharge
port while air‐free fuel, now heavier than air‐laden
fuel, flows by gravity back down into the impeller
and mixes with air, which continues to be drawn
from the suction line. As this cycle is repeated, all
air in the suction line is evacuated and a vacuum is
created. Atmospheric pressure forces the fuel in
the suction line to the impeller and pumping be
gins. Fuel no longer recirculates within the pump.
When pumping petroleum‐based fuels, fuel tem
perature is critical to maximum pumping efficiency
and performance. The temperature of the fuel must
remain below the temperature at which the fuel
tends to turn to vapor. If the fuel temperature ap
proaches its vapor pressure, the impeller will tend
to atomize the fuel, resulting in vapor pressure or
air bubbles. Air bubbles will burst in the eye of the
impeller, causing excessive vibration and shorten
ing pump life.
Whether new installation or rebuild of re
fueler, the following requirements apply:
1. It is essential that tank scale, dirt, and
any other foreign elements be re
moved from the tank and piping prior
to pump installation.
2. The gearbox was shipped dry of lu
bricant. Lubrication must be added
before any operation.
3. The pump must not be run dry of
product at any time.
This pump is designed for vehicular
mounting in petroleum service. Do not
attempt to pump corrosive materials, or
any liquids which may damage the
pump or endanger personnel as a result
of pump failure.
PRIMING
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 the pump and gearbox are
properly lubricated (see LUBRICATION in MAIN
TENANCE AND REPAIR).
Although this pump is self‐priming, it should never
be operated unless there is liquid in the pump cas
ing.
Never operate this pump unless there is
liquid in the pump casing. The pump will
not prime when dry. Extended operation of
a dry pump will destroy the seal assembly.
Add liquid to the pump casing when:
1. The pump is being put into service for the
first time.
2. The pump has not been used for a consider
able length of time.
3. The liquid in the pump casing has evapo
rated.
When installed in a flooded suction application,
simply open the system valves and permit the in
coming liquid to evacuate the air. After the pump
and piping system have completely filled, evacu
ate any remaining air pockets in the pump or suc
tion line by loosening a pipe plug or opening
bleeder valves.

OM-06273 0 SERIES
OPERATIONPAGE C - 2
Once the pump casing has been filled, the pump
will prime as long as positive suction head is avail
able.
To fill the pump, remove the fill plug in the top of the
pump casing and add clean liquid. Be certain to re
install the fill plug before operating the pump.
After filling the pump casing, do not at
tempt to operate the pump unless the fill
plug and all connecting piping is se
curely installed. Otherwise, liquid in the
pump could be forced out under pres
sure, resulting in injury to personnel.
GROUNDING
To eliminate electrostatic build‐up by the liquid be
ing pumped, the pump must be grounded by at
taching a ground wire to a ground rod (grounding
is not required if pumping water). Install the ground
rod in accordance with the National Electrical
Code and all local codes. Be sure the clamp or fas
tener has made a tight electrical connection with
the rod.
Inspect and test the ground wire assembly
for conductivity. Replace broken or frayed
wire before resuming operation.
STARTING
Consult the operations manual furnished with the
vehicle.
Rotation
The correct direction of pump rotation is counter‐
clockwise when facing the pump suction. The
pump could be damaged and performance ad
versely affected by incorrect rotation. If pump per
formance is not within the specified limits (see the
curve on page E‐1), check the direction of rotation
before further troubleshooting.
Only operate the input shaft in a counter‐
clockwise direction when facing the pump
suction. Otherwise, pump performance
will be adversely affected, and the pump
and/or gearbox could be seriously dam
aged.
OPERATION
Do not operate the pump against a
closed discharge valve for long periods
of time. If operated against a closed dis
charge valve, pump components will
deteriorate, and the liquid could come
to a boil, build pressure, and cause the
pump casing to rupture or explode.
Operating Controls
Since Gorman‐Rupp has no control over the actual
installation, it is the obligation of the tank builder or
the installer to devise controls to safely operate the
pump. All instructions and operational procedures
for the pump and system must be provided to the
pump operator.
OPERATING CHECKS
Lines With a Bypass
Since this pump does not have a suction check
valve, the discharge end of the bypass line must be
submerged in order to maintain suction.
Close the discharge throttling valve and open the
shutoff valve in the bypass line so that the pump
will not have to prime against the weight of the liq
uid in the discharge line. Start the hydraulic motor.
When the pump is fully primed and liquid is flowing
steadily from the bypass line, close the bypass
shutoff valve and open the discharge throttling
valve.
Lines Without a Bypass
Open all valves in the discharge line and start the
hydraulic motor. Priming is indicated by a positive

OM-06273
0 SERIES
OPERATION PAGE C - 3
reading on the discharge pressure gauge or by a
quieter operation. The pump may not prime imme
diately because the suction line must first fill with
liquid. If the pump fails to prime within five minutes,
stop it and check the suction line for leaks.
After the pump has been primed, partially close the
discharge line throttling valve in order to fill the line
slowly and guard against excessive shock pres
sure which could damage pipe ends, gaskets,
sprinkler heads, and any other fixtures connected
to the line. When the discharge line is completely
filled, adjust the throttling valve to the required flow
rate.
Leakage
No leakage should be visible at pump mating sur
faces, or at pump connections or fittings. Keep all
line connections and fittings tight to maintain maxi
mum pump efficiency.
Strainer Check
If a suction strainer has been shipped with the
pump or installed by the user, check the strainer
regularly, and clean it as necessary. The strainer
should also be checked if pump flow rate begins to
drop. If a vacuum suction gauge has been in
stalled, monitor and record the 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 (see Section E,
Page 1).
Liquid Temperature and Overheating
The maximum liquid temperature for this pump is
160_F (71_C). Do not apply it at a higher operating
temperature.
Overheating can occur if operated with the 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 and allow it to cool before servicing it. Refill
the pump casing with cool liquid.
Allow an over‐heated pump to cool be
fore servicing. Do not remove plates,
covers, gauges, pipe plugs, or fittings
from an overheated pump. Vapor pres
sure within the pump can cause parts
being disengaged to be ejected with
great force. After the pump cools, drain
the liquid from the pump by removing
the casing drain plug. Use caution when
removing the plug to prevent injury from
hot liquid.
Pump Vacuum Check
Since the pump does not have a suction check
valve, the discharge line must be fitted with a check
valve if a pump vacuum reading is taken.
With the pump inoperative, install a vacuum gauge
in the system, using pipe dope on the threads.
Block the suction line and start the pump. At oper
ating speed the pump should pull a vacuum of 15
to 17 inches (381 to 432 mm) or more of mercury
when pumping petroleum. If it does not, check for
air leaks in the seal, gasket, or discharge valve.
Open the suction line, and read the vacuum gauge
with the pump primed and at operation speed.
Shut off the pump. The vacuum gauge reading will
immediately drop proportionate to static suction
lift, and should then stabilize. 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 installation of the vacuum gauge.
NOTE
Petroleum products are very sensitive to changes
in temperature. Warmer temperatures elevate the
product vapor pressure resulting in low vacuum
readings. Do not mistake temperature problems for
faulty pump installation or performance.

OM-06273 0 SERIES
OPERATIONPAGE C - 4
STOPPING
Never halt the flow of liquid suddenly. If the liquid
being pumped is stopped abruptly, damaging
shock waves can be transmitted to the pump and
piping system. Close all connecting valves slowly.
After stopping the pump, take precautions to en
sure that the pump will remain inoperative.
COLD WEATHER PRESERVATION
Unless temperatures are extremely severe, below‐
freezing conditions will not affect pump operation
in petroleum service. However, during extremely
severe conditions care should be exercised during
start‐up, especially if the pump has been idle for
more than a few hours.

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP FAILS TO
PRIME
Strainer clogged. Check strainer and clean if neces
sary.
Suction lift or discharge head too high. Check piping installation and install
bypass line if needed. See INSTAL
LATION.
Leaking or worn seal or pump gasket. Check pump vacuum. Replace
leaking or worn seal or gasket.
Lining of suction hose collapsed. Replace suction hose.
Air leak in suction line. Correct leak.
PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE
Air leak in suction line. Correct leak.
Lining of suction hose collapsed. Replace suction hose.
Leaking or worn seal or pump gasket. Check pump vacuum. Replace
leaking or worn seal or gasket.
Suction intake not submerged at
proper level or sump too small.
Check installation and correct
submergence as needed.
Not enough liquid in cas
ing.
Add liquid to casing. See
PRIMING.
Pump speed too slow. Check power source output; con
sult power source operation man
ual.
OM-062730 SERIES
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 manual.
2. Disconnect the power source or take
other precautions to ensure that the
pump will remain inoperative.
3. Allow the pump to completely cool if
overheated.
4. Check the temperature before open
ing any covers, plates, or plugs.
5. Close the suction and discharge
valves.
6. Vent the pump slowly and cautiously.
7. Drain the pump.

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE (cont.)
PUMP REQUIRES
TOO MUCH
POWER
PUMP CLOGS
FREQUENTLY
Free impeller of debris.Impeller clogged.
Discharge head too low. Adjust discharge
valve.
Open discharge valve fully to in
crease flow rate, and run engine at
maximum governed speed.
Discharge flow too slow.
EXCESSIVE NOISE Cavitation in pump. Reduce suction lift and/or friction
losses in suction line. Record vac
uum and pressure gauge readings
and consult local representative or
factory.
Secure mounting hard
ware.
Pump or drive not securely mounted.
Locate and eliminate source of air
bubble.
Pumping entrained
air.
Strainer clogged. Check strainer and clean if neces
sary.
Pump speed too high. Check driver output; check that
sheaves or couplings are correctly
sized.
Suction lift or discharge head too high. Check piping installation and install
bypass line if needed. See INSTAL
LATION.
Discharge line clogged or restricted;
hose kinked.
Check discharge lines; straighten
hose.
Impeller clogged or damaged. Clean out debris; replace damaged
parts.
Pump speed too slow. Check power source output; con
sult power source operation man
ual.
BEARINGS
RUN
TOO HOT
Bearing temperature is high, but within
limits.
Check bearing temperature regu
larly to monitor any increase.
Low or incorrect lubricant. Check for proper type and level
of lubricant.
Suction and discharge lines not prop
erly supported.
Check piping installation for proper
support.
Drive misaligned.
Bearings in power source or gearbox Check bearings.
worn or binding.
Align drive properly.
Impeller or other wearing parts worn
or damaged.
Replace worn or damaged parts.
Check that impeller is properly
centered and rotates freely.
OM-06273 0 SERIES
TROUBLESHOOTINGPAGE D - 2

OM-062730 SERIES
TROUBLESHOOTING PAGE D - 3
PREVENTIVE MAINTENANCE
Since pump applications are seldom identical, and
pump wear is directly affected by such things as
the abrasive qualities, pressure and temperature
of the liquid being pumped, this section is intended
only to provide general recommendations and
practices for preventive maintenance. Regardless
of the application however, following a routine pre
ventive maintenance schedule will help assure
trouble‐free performance and long life from your
Gorman‐Rupp pump. For specific questions con
cerning your application, contact your Gorman‐
Rupp distributor or the Gorman‐Rupp Company.
Record keeping is an essential component of a
good preventive maintenance program. Changes
in suction and discharge gauge readings (if so
equipped) between regularly scheduled inspec
tions can indicate problems that can be corrected
before system damage or catastrophic failure oc
curs. The appearance of wearing parts should also
be documented at each inspection for comparison
as well. Also, if records indicate that a certain part
(such as the seal) fails at approximately the same
duty cycle, the part can be checked and replaced
before failure occurs, reducing unscheduled down
time.
For new applications, a first inspection of wearing
parts at 250 hours will give insight into the wear rate
for your particular application. Subsequent inspec
tions should be performed at the intervals shown
on the chart below. Critical applications should be
inspected more frequently.
General Condition (Temperature, Unusual
Noises or Vibrations, Cracks, Leaks,
Loose Hardware, Etc.) I
Pump Performance (Gauges, Speed, Flow) I
Bearing Lubrication I R
Seal Lubrication (And Packing Adjustment,
If So Equipped) I R
V‐Belts (If So Equipped) I
Air Release Valve Plunger Rod (If So Equipped) I C
Front Impeller Clearance (Wear Plate) I
Rear Impeller Clearance (Seal Plate) I
Check Valve I
Pressure Relief Valve (If So Equipped) C
Pump and Driver Alignment I
Shaft Deflection I
Bearings I
Bearing Housing I
Piping I
Driver Lubrication - See Mfgr's Literature
Legend:
I = Inspect, Clean, Adjust, Repair or Replace as Necessary
C = Clean
R = Replace
* Service interval based on an intermittent duty cycle equal to approximately 4000 hours annually.
Adjust schedule as required for lower or higher duty cycles or extreme operating conditions.
Preventive Maintenance Schedule
Item Daily Weekly Monthly Semi‐
Annually
Annually
Service Interval*

0 SERIES OM-06273
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.
STANDARD PERFORMANCE FOR PUMP MODEL 03H1-HYD (PETROLEUM SERVICE)
Based on 70_F (21_C) clear water at sea level
with minimum suction lift, corrected to 0.80 specific
gravity. Since pump installations are seldom identi
cal, your performance may be different due to such
factors as viscosity, specific gravity, elevation, tem
perature, and impeller trim.
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.
Pump speed and operating condition
points must be within the continuous per
formance range shown on the curve.

0 SERIESOM-06273
MAINTENANCE & REPAIRPAGE E - 2
STANDARD PERFORMANCE FOR PUMP MODEL 03H1-HYD (WATER SERVICE)
Based on 70_F (21_C) clear water at sea level
with minimum suction lift. Since pump installations
are seldom identical, your performance may be dif
ferent due to such factors as viscosity, specific
gravity, elevation, temperature, and impeller trim.
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.
Pump speed and operating condition
points must be within the continuous per
formance range shown on the curve.