GORMAN-RUPP 6500 Series User manual

OM-06700-01
October 27, 2014
GORMAN‐RUPP PUMPS
www.grpumps.com
e2014 Gorman‐Rupp Pumps Printed in U.S.A.
INSTALLATION, OPERATION,
AND MAINTENANCE MANUAL
WITH PARTS LIST
6500 SERIES PUMP
MODEL
6504C60-B

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needs this information when you require parts or service.
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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............................................
POSITIONING PUMP PAGE B -1.......................................................
Lifting PAGE B - 1.................................................................
Mounting PAGE B - 2.............................................................
SUCTION AND DISCHARGE PIPING PAGE B - 2.........................................
Materials PAGE B - 2..............................................................
Line Configuration PAGE B - 2......................................................
Connections to Pump PAGE B - 2..................................................
Gauges PAGE B - 2...............................................................
SUCTION LINES PAGE B - 2...........................................................
Fittings PAGE B - 2...............................................................
Strainers PAGE B - 2..............................................................
Sealing PAGE B - 2...............................................................
Suction Lines In Sumps PAGE B - 2.................................................
Suction Line Positioning PAGE B - 3................................................
DISCHARGE LINES PAGE B - 4........................................................
Siphoning PAGE B - 4.............................................................
Valves PAGE B - 4................................................................
ALIGNMENT PAGE B - 4..............................................................
Coupled Drives PAGE B - 4........................................................
V‐Belt Drives PAGE B - 5...........................................................
ELECTRICAL CONNECTIONS PAGE B - 5...............................................
OPERATION - SECTION C PAGE C - 1......................................
PRIMING PAGE C - 1.................................................................
Hand Primers PAGE C - 1..........................................................
Exhaust Primers PAGE C - 1.......................................................
Auxiliary Ejectors PAGE C - 2.......................................................
Vacuum Pumps PAGE C - 2........................................................
STARTING PAGE C - 2................................................................
Rotation PAGE C - 2..............................................................
OPERATION PAGE C - 2..............................................................
Leakage PAGE C - 2..............................................................
Liquid Temperature And Overheating PAGE C - 2.....................................
Strainer Check PAGE C - 3.........................................................
Pump Vacuum Check PAGE C - 3..................................................
Operational Checks PAGE C - 3....................................................
STOPPING PAGE C - 3................................................................
Cold Weather Preservation PAGE C - 4..............................................
BEARING TEMPERATURE CHECK PAGE C - 4..........................................
LUBRICATION PAGE C - 4.............................................................
Power Source PAGE C - 5.........................................................

TABLE OF CONTENTS
(continued)
ii
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 LIST:
Pump End Assembly PAGE E - 3...................................................
Repair Rotating Assembly PAGE E - 5...............................................
PUMP AND SEAL DISASSEMBLY AND REASSEMBLY PAGE E - 6.........................
Suction Head and Wear Ring Removal PAGE E - 7....................................
Pump Casing Removal PAGE E - 7.................................................
Draining Oil From Seal Cavity PAGE E - 7............................................
Impeller Removal PAGE E - 7......................................................
Seal Removal PAGE E - 8..........................................................
Separating Rotating Assembly From Power Source PAGE E - 8........................
Shaft and Bearing Removal And Disassembly PAGE E - 8.............................
Shaft and Bearing Reassembly and Installation PAGE E - 9............................
Securing Rotating Assembly to Power Source PAGE E - 10.............................
Seal Reassembly and Installation PAGE E - 10........................................
Impeller Installation and Adjustment PAGE E - 11......................................
Pump Casing Installation PAGE E - 12................................................
Suction Head and Wear Ring Installation PAGE E - 12..................................
LUBRICATION PAGE E - 12.............................................................
Seal Assembly PAGE E - 12.........................................................
Bearings PAGE E - 12..............................................................

6500 SERIES OM-06700
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.

6500 SERIES OM-06700
PAGE A - 1SAFETY
SAFETY ‐ SECTION A
This information applies to 6500 Series
basic pumps. Gorman‐Rupp has no
control over or particular knowledge of
the power source which will be used.
Refer to the manual accompanying the
power source before attempting to be
gin operation.
Because pump installations are seldom
identical, this manual cannot possibly
provide detailed instructions and pre
cautions for each specific application.
Therefore, it is the owner/installer's re
sponsibility to ensure that applications
not addressed in this manual are per
formed only after establishing that nei
ther operator safety nor pump integrity
are compromised by the installation.
Before attempting to open or service the
pump:
1. Familiarize yourself with this man
ual.
2. Lock out or disconnect the power
source 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.
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 without the
shields and/or guards in place over the
drive shaft, belts, and/or couplings, or
other rotating parts. Exposed rotating
parts can catch clothing, fingers, or
tools, causing severe injury to person
nel.
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.
Overheated pumps can cause severe

6500 SERIESOM-06700
PAGE A - 2 SAFETY
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.
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.
Never run this pump backwards. Be cer
tain that rotation is correct before fully
engaging the pump.
Pumps and related equipment must be in
stalled and operated according to all na
tional, local and industry standards.

6500 SERIES OM-06700
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 flooded suc
tion application where the liquid is supplied to the
pump under pressure. Since the pressure sup
plied to the pump is critical to performance and
safety, be sure to limit the incoming pressure to
50% of the maximum permissible operating pres
sure as shown on the pump performance curve
(see Section E, Page 1).
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 6504C60-B
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 and engine 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
fer to LUBRICATION in the MAINTENANCE

OM-06700 6500 SERIES
PAGE B - 2 INSTALLATION
AND REPAIR section of this manual and per
form duties as instructed.
e. 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.
Proper mounting of the pump, driver and base is
critical to the performance of the pump. Improper
mounting can result in vibration, which can cause
damage to the pump and/or other system compo
nents.
The pumping unit must be securely mounted to a
foundation that is heavy enough to absorb any vi
bration, strain or shock, while providing perma
nent, rigid support for the unit.
Because pump installations vary due to the specif
ic application, this manual cannot possibly antici
pate and provide detailed instructions for every in
stallation. Therefore, it is recommended that the in
staller of the unit follow the recommendations pro
vided by the Hydraulic Institute in their Rotodynam
ic Centrifugal Pump Design and Application manu
al when designing and fabricating the foundation
upon which the pump, base and driver will be
mounted.
SUCTION AND DISCHARGE PIPING
The following is provided as general information for
suction and discharge piping. Because pump in
stallations vary due to the specific application, this
manual cannot possibly anticipate and provide de
tailed instructions for every installation. Therefore,
it is recommended that the installer follow the rec
ommendations provided by the Hydraulic Institute
in their Pump Piping for Rotodynamic Pumps man
ual for layout, design and installation of the system
piping.
Materials
Materials used in piping must be compatible with
the liquid being pumped. Using piping couplings
in suction lines is not recommended.
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.

6500 SERIES OM-06700
PAGE B - 3INSTALLATION
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.
Gauges
Most pumps are drilled and tapped for installing
discharge pressure and vacuum suction gauges.
If these gauges are desired for pumps that are not
tapped, drill and tap the suction and discharge
lines not less than 18 inches (457,2 mm) from the
suction and discharge ports and install the lines.
Installation closer to the pump may result in erratic
readings.
SUCTION LINES
To avoid air pockets which could affect pump prim
ing, the suction line must be as short and direct as
possible.
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 for
isolation purposes, install it with the stem horizon
tal to avoid air pockets.
Strainers
If a strainer is installed by the pump user, make cer
tain that the total area of the openings in the strain
er is at least three or four times the cross section of
the suction line, and that the openings will not per
mit passage of solids larger than the solids han
dling capability of the pump.
This pump is designed to handle up to 1/2‐inch
(12,7 mm) diameter spherical solids.
Sealing
Since even a slight leak will affect pump perfor
mance, all connections in the suction line should
be sealed with pipe dope to ensure an airtight seal.
Follow the sealant manufacturer's recommenda
tions when selecting and applying the pipe dope.
The pipe dope should be compatible with the liquid
being pumped.
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.
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.
ALIGNMENT
This pump is designed for direct coupled
drive only. Use of a V‐belt drive will dam
age the pump and void the pump warranty.
The alignment of the pump and its power source is
critical for trouble‐free mechanical operation. The
driver and pump must be mounted so that their

OM-06700 6500 SERIES
PAGE B - 4 INSTALLATION
shafts are aligned with and parallel to each other. It
is imperative that alignment be checked after the
pump and piping are installed, and before opera
tion.
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.
Coupled Drives
When using couplings, the axis of the power
source must be aligned to the axis of the pump
shaft in both the horizontal and vertical planes.
Most couplings require a specific gap or clearance
between the driving and the driven shafts. Refer to
the coupling manufacturer's service literature.
Align spider insert type couplings by using calipers
to measure the dimensions on the circumference
of the outer ends of the coupling hub every 90_.
The coupling is in alignment when the hub ends
are the same distance apart at all points (see Fig
ure 2A).
Figure 2A. Aligning Spider‐Type Couplings
Figure 2B. Aligning Non‐Spider Type Couplings
Align non‐spider type couplings by using a feeler
gauge or taper gauge between the coupling halves
every 90_. The coupling is in alignment when the
hubs are the same distance apart at all points (see
Figure 2B).
Check parallel adjustment by laying a straightedge
across both coupling rims at the top, bottom, and
side. When the straightedge rests evenly on both
halves of the coupling, the coupling is in horizontal
parallel alignment. If the coupling is misaligned,
use a feeler gauge between the coupling and the
straightedge to measure the amount of misalign
ment.
Do not operate the pump without the
guard in place over the rotating parts.
exposed rotating parts can catch cloth
ing, fingers, or tools, causing severe in
jury to personnel.

OM-06700
6500 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 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.
STARTING
Consult the operations manual furnished with the
power source.
OPERATION
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.
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, or fittings from an over‐
heated pump. Liquid within the pump
can reach boiling temperatures, and va
por pressure 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 re
moving the casing drain plug. Use cau
tion when removing the plug to prevent
injury to personnel from hot liquid.
Strainer Check
If a suction strainer has been installed by the user,
check the strainer regularly and clean it as neces
sary. The strainer should also be checked if pump
flow rate begins to drop. If a vacuum suction gauge
has been installed, monitor and record the read
ings 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).
STOPPING
If the liquid being pumped is stopped abruptly,
damaging shock waves can be transmitted to the
pump and piping system. Soft‐start systems with
ramp up/ramp down starting and stopping capa
bilities are available where water hammer may be a
problem.
After stopping the pump, lock out or disconnect
the power source to ensure that the pump will re
main inoperative.

OM-06700 6500 SERIES
OPERATIONPAGE C - 2
Cold Weather Preservation
In below freezing conditions, drain the pump to
prevent damage from freezing. Also, clean out any
solids by flushing with a hose. Operate the pump
for approximately one minute; this will remove any
remaining liquid that could freeze the pump rotat
ing parts. If the pump will be idle for more than a
few hours, or if it has been pumping liquids con
taining a large amount of solids, drain the pump,
and flush it thoroughly with clean water. To prevent
large solids from clogging the drain port and pre
venting the pump from completely draining, insert
a rod or stiff wire in the drain port, and agitate the
liquid during the draining process. Clean out any
remaining solids by flushing with a hose.
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 Section E). Bear
ing 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.

OM-067006500 SERIES
TROUBLESHOOTING PAGE D - 1
TROUBLESHOOTING - SECTION B
Review all SAFETY information in Section A.
Before attempting to open or service the
pump:
1. Familiarize yourself with this manual.
2. Lock out or disconnect the power
source and take the necessary pre
cautions 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.
Table D‐1 Troubleshooting Chart
TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP FAILS TO PRIME Auxiliary priming device faulty or im
properly installed.
Discharge check valve open.
Air leak in suction line.
Lining of suction hose collapsed.
Leaking or worn seal or pump gas
ket.
Strainer clogged.
Repair priming device or check
installation.
Check position of handle; close
valve.
Correct leak.
Replace suction hose.
Check pump vacuum. Replace leak
ing or worn seal or gasket.
Check strainer and clean if neces
sary.
PUMP STOPS OR FAILS
TO DELIVER RATED
FLOW OR PRESSURE
Air leak in suction line.
Lining of suction hose collapsed.
Suction intake not submerged at
proper level or sump too small.
Strainer clogged.
Correct leak.
Replace suction hose.
Check installation and correct sub
mergence as needed.
Check strainer and clean if neces
sary.

OM-06700 6500 SERIES
TROUBLESHOOTINGPAGE D - 2
Table D‐1 Troubleshooting Chart (Continued)
TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP STOPS OR FAILS
TO DELIVER RATED
FLOW OR PRESSURE
(cont.)
Impeller or other wearing parts worn
or damaged.
Leaking or worn seal or pump gas
ket.
Impeller clogged.
Pump running backwards (electric
motor driven models).
Suction lift or discharge head too
high.
Liquid solution too thick.
Replace worn or damaged parts.
Check that impeller is properly cen
tered and rotates freely.
Check pump vacuum. Replace leak
ing or worn seal or gasket.
Free impeller of debris.
Check direction of rotation. Correct
3‐phase wiring by interchanging any
two motor leads at control box. (See
Pump Rotation in the Installation
and Operations Manual.)
Check piping installation and install
bypass line if needed. See INSTAL
LATION in the Installation and Op
erations manual.
Dilute if possible.
PUMP REQUIRES TOO
MUCH POWER
Pump speed too high.
Discharge head too low.
Liquid solution too thick.
Impeller jammed due to debris or in
sufficient clearance.
Check governor setting (engine driv
en models).
Adjust discharge valve.
Dilute if possible.
Disassemble pump and check impel
ler.
PUMP CLOGS
FREQUENTLY
Discharge flow too slow.
Suction check valve or foot valve
clogged or binding.
Open discharge valve filly to in
crease flow rate, and run power
source at maximum governed
speed.
Clean valve.
EXCESSIVE NOISE Cavitation in pump.
Pumping entrained air.
Pump or drive not securely
mounted.
Impeller clogged or damaged.
Reduce suction lift and/or friction
losses in suction line. Record vacu
um and pressure gauge readings
and consult local representative or
factory.
Locate and eliminate source of air
bubble.
Secure mounting hardware.
Clean out debris; replace damaged
parts.

OM-067006500 SERIES
TROUBLESHOOTING PAGE D - 3
Table D‐1 Troubleshooting Chart (Continued)
TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
BEARINGS RUN TOO
HOT
Bearing temperature is high, but with
in limits.
Low or incorrect lubricant.
Check bearing temperature regularly
to monitor any increase
Check for proper type and level of lu
bricant.
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.

OM-06700 6500 SERIES
TROUBLESHOOTINGPAGE D - 4
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 intermittant 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*

6500 SERIES OM-06700
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 PERFORMANCES FOR PUMP MODEL 6504C60-B
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
ference 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.

6500 SERIESOM-06700
MAINTENANCE & REPAIRPAGE E - 2
ILLUSTRATION
PARTSPAGE
Figure 1. Pump Assembly 6504C60-B

6500 SERIES OM-06700
MAINTENANCE & REPAIR PAGE E - 3
PARTS LIST
Pump Assembly 6504C60-B
(From S/N 1594122 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.
ITEM
NO. PART NAME PART NUMBER QTY
1 SPOOL FLANGE 6" 11402B 10010 1
2 PIPE PLUG P04 15079 1
.2A PIPE PLUG P04 15079 1
3 HEX NUT D12 15991 28
4 LOCK WASHER J12 15991 28
5 PIPE PLUG P20 10009 1
6 STUD C1212 15991 4
7 SUCTION HEAD 38246-615 11010 1
8WEAR RING 38691-369 11010 1
9O‐RING 25152-384 1
9A O‐RING 25152-384 1
.10 PUMP CASING SEE NOTE BELOW 1
.11 STUD C1211 15991 16
.12 PIPE PLUG P08 15079 3
13 REPAIR ROTATING ASSY 44163-541 1
14 GASKET 25113-036 1
15 BEARING STAND 41583-241 24150 1
16 STAND 34265-067 15080 1
17 HEX HEAD CAP SCREW B1210 15991 4
18 STUD C1214 15991 4
19 FLAT WASHER K12 15991 4
NOT SHOWN:
ROTATION DECAL 2613M 1
NAMEPLATE 38819-002 13000 1
DRIVE SCREW BM#04-03 17000 4
SUCTION STICKER 6588AG 1
DISCHARGE STICKER 6588BJ 1
G‐R DECAL 6" GR-06 1
WARNING DECAL 2613FE 1
LUBE DECAL 11421A 1
OIL LEVEL DECAL 38816-123 1
INSTRUCTION TAG 38817-011 1
.INCLUDED W/REPAIR PUMP CASING ASSY 46474-909 1
INDICATES PARTS RECOMMENDED FOR STOCK