Gorman-Rupp Pumps VG5C3-B User Manual

ACE

OM-02816-02

September 11, 2000

Rev. A 02‐06‐14

INSTALLATION, OPERATION,

AND MAINTENANCE MANUAL

WITH PARTS LIST

VG SERIES PUMP

MODEL

VG5C3-B

THE GORMAN‐RUPP COMPANY  MANSFIELD, OHIO

www.grpumps.com

GORMAN‐RUPP OF CANADA LIMITED  ST. THOMAS, ONTARIO, CANADA Printed in U.S.A.

2000 The Gorman‐Rupp Company

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

INTRODUCTION PAGE I - 1.................................................

WARNINGS - SECTION A PAGE A - 1.......................................

INSTALLATION - SECTION B PAGE B - 1....................................

Pump Dimensions PAGE B - 1.....................................................

PREINSTALLATION INSPECTION PAGE B - 2............................................

POSITIONING PUMP PAGE B - 2.......................................................

Lifting PAGE B - 2.................................................................

Mounting PAGE B - 2.............................................................

SUCTION AND DISCHARGE PIPING PAGE B - 2.........................................

Materials PAGE B - 2..............................................................

Line Configuration PAGE B - 2......................................................

Connections to Pump PAGE B - 3..................................................

Gauges PAGE B - 3...............................................................

SUCTION LINES PAGE B - 3...........................................................

Fittings PAGE B - 3...............................................................

Strainers PAGE B - 3..............................................................

Sealing PAGE B - 3...............................................................

Suction Lines In Sumps PAGE B - 3.................................................

Suction Line Positioning PAGE B - 4................................................

DISCHARGE LINES PAGE B - 4........................................................

Siphoning PAGE B - 4.............................................................

Valves PAGE B - 4................................................................

ALIGNMENT PAGE B - 5..............................................................

Coupled Drives PAGE B - 5........................................................

V-Belt Drives 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..................................................

STOPPING PAGE C - 3................................................................

Cold Weather Preservation PAGE C - 3..............................................

BEARING TEMPERATURE CHECK PAGE C - 4..........................................

TROUBLESHOOTING - SECTION D PAGE D - 1..............................

PREVENTIVE MAINTENANCE PAGE D - 3...............................................

i

TABLE OF CONTENTS

(continued)

PUMP MAINTENANCE AND REPAIR - SECTION E PAGE E - 1................

STANDARD PERFORMANCE CURVE PAGE E - 1........................................

PUMP MODEL - PARTS LIST PAGE E - 3...............................................

PUMP AND SEAL DISASSEMBLY AND REASSEMBLY PAGE E - 4.........................

Impeller Removal PAGE E - 4......................................................

Seal Removal PAGE E - 4..........................................................

Shaft And Bearing Removal And Disassembly PAGE E - 5.............................

Shaft And Bearing Reassembly And Installation PAGE E - 6............................

Seal Reassembly and Installation PAGE E - 7........................................

Impeller Installation PAGE E - 8.....................................................

Final Pump Assembly PAGE E - 8..................................................

LUBRICATION PAGE E - 8.............................................................

Seal Assembly PAGE E - 8.........................................................

Bearings PAGE E - 8..............................................................

Power Source PAGE E - 9.........................................................

ii

VG SERIES OM-02816

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 a VG Series, enclosed impeller, cen
trifugal model with straight‐in suction without a
suction check valve. The pump is designed for
high pressure distribution of liquids containing
specified entrained solids. The basic material of
construction for wetted parts is gray iron. Be sure
the liquid being pumped is compatible with this
material.

This manual will alert personnel to known proce
dures which require special attention, to those
which could damage equipment, and to those
which could be dangerous to personnel. However,
this manual cannot possibly anticipate and provide
detailed precautions for every situation that might
occur during maintenance of the unit. Therefore, it
is the responsibility of the owner/maintenance per
sonnel to ensure that only safe, established main
tenance procedures are used, and that any proce
dures not addressed in this manual are performed
only after establishing that neither personal safety
nor pump integrity are compromised by such prac
tices.

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.

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.

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.

PAGE I - 1INTRODUCTION

VG SERIES OM-02816

SAFETY - SECTION A

This information applies to VG 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.

containing specified entrained solids.
Do not attempt to pump volatile, corro
sive, or flammable materials which may
damage the pump or endanger person
nel as a result of pump failure.

After the pump has been positioned,
make certain that the pump and all pip
ing connections are tight, properly sup
ported and secure before operation.

Do not operate the pump without the
guards in place over the rotating parts.
Exposed rotating parts can catch cloth
ing, fingers, or tools, causing severe in
jury to personnel.

Before attempting to open or service the
pump:

1. Familiarize yourself with this man
ual.

2. Disconnect or lock out 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.

This pump is designed to handle liquids

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.

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

PAGE A - 1SAFETY

OM-02816

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.

VG SERIES

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.

PAGE A - 2 SAFETY

INSTALLATION - SECTION B

OM-02816VG SERIES

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 posi
tioned 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

OUTLINE DRAWING

configuration, and priming must be tailored to the
specific application. Since the pressure supplied
to the pump is critical to performance and safety,
be sure to limit the incoming pressure to 50% of
the maximum permissible operating pressure as
shown on the pump performance curve.

For further assistance, contact your Gorman‐Rupp
distributor or the Gorman‐Rupp Company.

Pump Dimensions

See Figure 1
sions of this pump.

for the approximate physical dimen

Figure 1. Pump Model VG5C3-B

PAGE B - 1INSTALLATION

OM-02816 VG SERIES

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 warnings and cautions con

tained in this manual or affixed to the pump,
and perform all duties indicated. Note the di
rection of rotation indicated on the pump.
Check that the pump shaft rotates counter
clockwise when facing the pump suction.

POSITIONING PUMP

Lifting

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.

Only operate this pump in the direction in
dicated by the arrow on the pump body
and on the accompanying decal. Refer to
ROTATION in OPERATION, Section C.

d. Check all lubricant levels and lubricate as

necessary. Refer to LUBRICATION in the
MAINTENANCE AND REPAIR section of this
manual and perform duties as instructed.

e. If the pump and power source have been

stored for more than 12 months, some of the
components or lubricants may have ex
ceeded their maximum shelf life. These must
be inspected or replaced to ensure maxi
mum pump service.

If the maximum shelf life has been exceeded, or if
anything appears to be abnormal, contact your
Gorman‐Rupp distributor or the factory to deter
mine the repair or updating policy. Do not put the
pump into service until appropriate action has
been taken.

Pump unit weights will vary depending on the
mounting and drive provided. Check the shipping
tag on the unit packaging for the actual weight, and
use lifting equipment with appropriate capacity.
Drain the pump and remove all customer‐installed
equipment such as suction and discharge hoses
or piping before attempting to lift existing, installed
units.

Mounting

Locate the pump in an accessible place as close as
practical to the liquid being pumped. Level mount
ing is essential for proper operation.

The pump may have to be supported or shimmed
to provide for level operation or to eliminate vibra
tion.

SUCTION AND DISCHARGE PIPING

The size of the system piping is not always deter
mined by the nominal suction and discharge port
diameter. Factors such as suction lift, discharge
elevation, and friction losses for the complete sys
tem must be considered to be sure your applica
tion allows the pump to operate within the safe op
erating range shown on page E‐1. In any case, the

PAGE B - 2 INSTALLATION

OM-02816VG SERIES

suction line should never be smaller than the pump
inlet.

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

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

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.

Before tightening a connecting flange, align it ex
actly with the pump port. Never pull a pipe line into
place by tightening the flange bolts and/or cou
plings.

Lines near the pump must be independently sup
ported to avoid strain on the pump which could
cause excessive vibration, decreased bearing life,
and increased shaft and seal wear. If hose‐type
lines are used, they should have adequate support
to secure them when filled with liquid and under
pressure.

Gauges

Most pumps are drilled and tapped for installing
discharge pressure and vacuum suction gauges.
If these gauges are desired for pumps that are not
tapped, drill and tap the suction and discharge
lines not less than 18 inches (457,2 mm) from the
suction and discharge ports and install the lines.
Installation closer to the pump may result in erratic
readings.

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 3/4 inch
(19,1 mm) diameter spherical solids.

Sealing

Since even a slight leak will affect priming, head,
and capacity, especially when operating with a
high suction lift, all connections in the suction line
should be sealed with pipe dope to ensure an air
tight seal. Follow the sealant manufacturer's rec
ommendations when selecting and applying the
pipe dope. The pipe dope should be compatible
with the liquid being pumped.

Suction Lines In Sumps

SUCTION LINES

To avoid air pockets which could affect pump prim
ing, the suction line must be as short and direct as

If a single suction line is installed in a sump, it
should be positioned away from the wall of the
sump at a distance equal to 1 1/2 times the diame
ter of the suction line.

PAGE B - 3INSTALLATION

OM-02816 VG SERIES

If there is a liquid flow from an open pipe into the
sump, the flow should be kept away from the suc
tion inlet because the inflow will carry air down into
the sump, and air entering the suction line will re
duce pump efficiency.

If it is necessary to position inflow close to the suc
tion inlet, install a baffle between the inflow and the
suction inlet at a distance 1 1/2 times the diameter
of the suction pipe. The baffle will allow entrained
air to escape from the liquid before it is drawn into
the suction inlet.

If two suction lines are installed in a single sump,
the flow paths may interact, reducing the efficiency
of one or both pumps. To avoid this, position the
suction inlets so that they are separated by a dis

tance equal to at least 3 times the diameter of the
suction pipe.

Suction Line Positioning

The depth of submergence of the suction line is
critical to efficient pump operation.
recommended minimum submergence vs. veloc

ity.

Figure 2 shows

NOTE

The pipe submergence required may be reduced
by installing a standard pipe increaser fitting at the
end of the suction line. The larger opening size will
reduce the inlet velocity. Calculate the required
submergence using the following formula based
on the increased opening size (area or diameter).

Figure 2. Recommended Minimum Suction Line Submergence vs. Velocity

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

PAGE B - 4 INSTALLATION

phoning action causing damage to the pump
could result.

Valves

A check valve in the discharge line is normally rec
ommended, but it is not necessary in low dis
charge head applications.

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

The alignment of the pump and its power source is
critical for trouble‐free mechanical operation. In
either a flexible coupling or V‐belt driven system,
the driver and pump must be mounted so that their
shafts are aligned with and parallel to each other. It
is imperative that alignment be checked after the
pump and piping are installed, and before opera
tion.

OM-02816VG SERIES

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 3A).

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.

Figure 3A. Aligning Spider‐Type Couplings

Figure 3B. 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 3B).

PAGE B - 5INSTALLATION

OM-02816 VG SERIES

Check parallel adjustment by laying a straightedge
across both coupling rims at the top, bottom, and
side. When the straightedge rests evenly on both
halves of the coupling, the coupling is in horizontal
parallel alignment. If the coupling is misaligned,
use a feeler gauge between the coupling and the
straightedge to measure the amount of misalign
ment.

V‐Belt Drives

When using V‐belt drives, the power source and
the pump must be parallel. Use a straightedge
along the sides of the pulleys to ensure that the pul
leys are properly aligned (see Figure 3C). In drive
systems using two or more belts, make certain that
the belts are a matched set; unmatched sets will
cause accelerated belt wear.

Tighten the belts in accordance with the belt manu
facturer's instructions. If the belts are too loose,
they will slip; if the belts are too tight, there will be
excessive power loss and possible bearing failure.
Select pulleys that will match the proper speed ra
tio; overspeeding the pump may damage both
pump and power source.

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.

MISALIGNED:

SHAFTS

NOT PARALLEL

MISALIGNED:

SHAFTS

NOT IN LINE

ALIGNED: SHAFTS

PARALLEL AND

SHEAVES IN LINE

Figure 3C. Alignment of V‐Belt Driven Pumps

PAGE B - 6 INSTALLATION

VG SERIES

OM-02816

OPERATION - SECTION C

Review all SAFETY information in Section A.

Follow the instructions on all tags, labels and de
cals attached to the pump.

This pump is designed to handle 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.

Pump speed and operating conditions
must be within the performance range
shown on page E‐1.

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 is properly lubri
cated (see LUBRICATION in MAINTENANCE
AND REPAIR).

This is not a self‐priming pump, so an external
priming device must be used if the pump is in
stalled on a suction lift. A foot valve may be in
stalled at the end of the suction pipe to maintain the
prime; however, this may adversely affect pump
performance due to friction loss. Many standard
centrifugal models are equipped with a hand‐oper
ated vacuum pump, exhaust primer, or ejector for
this purpose. If a priming device was not furnished
with the pump, it may be ordered from the factory
as an option. Before attempting to operate the
priming device, close the discharge throttling
valve. (Installation of a spring‐loaded check valve
is also recommended to facilitate priming.) Once
the pump is fully primed, close the valve between

the priming device and pump to preserve the
prime. Start the pump and open the discharge
valve slowly to fill the discharge line. When installed
in a flooded suction application, simply open the
system valves and permit the incoming liquid to
evacuate the air. After the pump and piping system
have completely filled, evacuate any remaining air
pockets in the pump or suction line.

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.

Hand Primers

Hand‐operated primers are usually mounted on
the pump and, when operated, draw air out of the
suction line and pump casing. To prime a pump
with a hand vacuum pump, open the cock on the
pump priming line. Operate the hand pump until
liquid flows out of the check valve on the bottom of
the primer pump. Once the pump is primed, close
the valve located between the primer and the
pump so that the prime will not be lost.

HANDLE

DRAIN

COCK

Figure 1. Hand Primer Assembly

Exhaust Primers

Engine driven pumps normally take advantage of
the engine exhaust gases by using them to operate
an exhaust primer. The exhaust is directed through

OPERATION PAGE C - 1

VG SERIESOM-02816

a venturi which creates a vacuum in the pump cas
ing in order to fill the suction line and pump casing
with liquid. To prime a pump using an exhaust
primer, open the gas cock in the priming line and
engage the exhaust primer until liquid is thrown out
of the ejector nozzle.

HANDLE

GAS

COCK

Figure 2. Exhaust Primer Assembly

Air can be exhausted to prime a pump by using a
vacuum pump. Either a wet type or a dry type vac
uum pump may be used; however, a wet type is
preferred since it will not be damaged if liquid en
ters it. If a dry vacuum pump is used, provisions
must be made to keep liquid from entering it.

Auxiliary Ejectors

Rotation

The correct direction of pump rotation is counter
clockwise when facing the impeller. If the pump is
operated in the wrong direction, pump perform
ance could be adversely affected, and the pump
could be seriously damaged.

Only operate this pump in the direction in
dicated by the arrow on the pump body
and on the accompanying decal. Other
wise, pump performance could be ad
versely affected, and the pump could be
seriously damaged.

Consult the operating manual furnished with the
power source before attempting to start the power
source.

If an electric motor is used to drive the pump, re
move V‐belts, couplings, or otherwise disconnect
the pump from the motor before checking motor
rotation. Operate the motor independently while
observing the direction of the motor shaft, or cool
ing fan.

Ejectors function much like exhaust primers. They
may be operated by steam, compressed air, water
or exhaust gases. To prime a pump using an ejec
tor, open the gas cock in the priming line and oper
ate the ejector until liquid is thrown out the ejector
nozzle.

Vacuum Pumps

Air can be exhausted to prime a pump by using a
vacuum pump. Either a wet type or a dry type vac
uum pump may be used; however, a wet type is
preferred since it will not be damaged if liquid en
ters it. If a dry vacuum pump is used, provisions
must be made to keep liquid from entering it.

STARTING

Consult the operations manual furnished with the
power source.

If rotation is incorrect on a three‐phase motor, have
a qualified electrician interchange any two of the
three‐phase wires to change direction. If rotation is
incorrect on a single‐phase motor, consult the lit
erature supplied with the motor for specific instruc
tions.

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

OPERATIONPAGE C - 2

VG SERIES

OM-02816

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

inches (508,0 mm) or more of mercury. If it does
not, check for air leaks in the seal, gasket, or dis
charge 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.

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.

On engine driven pumps, reduce the throttle
speed slowly and allow the engine to idle briefly be
fore stopping.

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.

Pump Vacuum Check

Since this pump does not have a suction check
valve, the discharge line must be fitted with a check
valve if a pump vacuum reading is to be 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 20

If the application involves a high discharge
head, gradually close the discharge
throttling valve before stopping the pump.

After stopping the pump, disconnect the power
source to ensure that the pump will remain inop
erative.

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.

OPERATION PAGE C - 3

VG SERIESOM-02816

BEARING TEMPERATURE CHECK

Bearings normally run at higher than ambient tem
peratures because of heat generated by friction.
Temperatures up to 160
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.



F (71C) are considered

A sudden increase in bearing temperature 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 MAINTENANCE
AND REPAIR). Bearing overheating can also be
caused by shaft misalignment and/or excessive vi
bration.

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.

OPERATIONPAGE C - 4

VG‐SERIES OM-02816

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. 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 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 FAILS TO
PRIME

PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE

Auxiliary priming device faulty or im
properly installed.

Discharge check valve open. Check position of handle; close

Strainer clogged. Check strainer and clean if neces

Air leak in suction line.

Lining of suction hose collapsed.

Leaking or worn seal or pump gasket. Check pump vacuum. Replace

Pump running backwards. Check direction of rotation.

Strainer clogged. Check strainer and clean if neces

Air leak in suction line. Correct leak.

Suction intake not submerged at
proper level or sump too small.

Repair priming device or check in
stallation.

valve.

sary.

Correct leak.

Replace suction hose.

leaking or worn seal or gasket.

sary.

Check installation and correct sub
mergence as needed.

Impeller or other wearing parts worn
or damaged.

Impeller clogged. Free impeller of debris.

TROUBLESHOOTING PAGE D - 1

Replace worn or damaged parts.
Check that impeller is properly
centered and rotates freely.

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY

VG‐SERIESOM-02816

PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE (cont.)

PUMP REQUIRES
TOO MUCH
POWER

Discharge throttling valve partially
closed; check that valve is installed im
properly.

Pump speed too slow. Check driver output; check belts

Suction lift too high. Measure lift w/vacuum gauge. Re

Leaking or worn seal or pump gasket. Check pump vacuum. Replace

Liquid solution too thick. Dilute if possible.

Power source too small. Check power requirement for ap

Pump speed too high. Check driver output; check that

Discharge head too low. Adjust discharge valve.

Impeller jammed due to debris or in
sufficient clearance.

Open discharge valve fully; check
piping installation.

or couplings for slippage.

duce lift and/or friction losses in
suction line.

leaking or worn seal or gasket.

plication. Install larger power
source.

sheaves or couplings are cor
rectly sized.

Disassemble pump and check im
peller.

Liquid solution too thick. Dilute if possible.

Bearing(s) frozen. Disassemble pump and check

PUMP CLOGS
FREQUENTLY

EXCESSIVE NOISE Cavitation in pump.

Discharge flow too slow. Open discharge valve fully to in

Suction check valve or foot valve
clogged or binding.

Pumping entrained air.

Pump or drive not securely mounted.

Impeller clogged or damaged.

bearing(s).

crease flow rate, and run power
source at maximum governed
speed.

Clean valve.

Reduce suction lift and/or friction
losses in suction line. Record vac
uum and pressure gauge readings
and consult local representative or
factory.

Locate and eliminate source of air
bubble.

Secure mounting hardware.

Clean out debris; replace dam
aged parts.

Suction and discharge lines not prop
erly supported.

Check piping installation for proper
support.

TROUBLESHOOTINGPAGE D - 2

VG‐SERIES OM-02816

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY

BEARINGS RUN
TOO HOT

Bearing temperature is high, but
within limits.

Low or incorrect lubricant. Check for proper type and level of

Pump speed too high. Reduce speed of power source.

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

Check bearing temperature regu
larly to monitor any increase.

lubricant.

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.

TROUBLESHOOTING PAGE D - 3

VG‐SERIESOM-02816

Preventive Maintenance Schedule

Service Interval*

Item

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

Daily Weekly Monthly Semi‐

Annually

Annually

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.

TROUBLESHOOTINGPAGE D - 4

OM-02816VG SERIES

PUMP MAINTENANCE AND REPAIR - SECTION E

MAINTENANCE AND REPAIR OF THE WEARING PARTS OF THE PUMP WILL MAINTAIN PEAK OPER
ATING PERFORMANCE.

STANDARD PERFORMANCE FOR PUMP MODEL VG5C3-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
ferent due to such factors as viscosity, specific
gravity, elevation, temperature, and impeller trim.

Contact the Gorman‐Rupp Company to verify per
formance or part numbers.

Pump speed and operating condition

If your pump serial number is followed by an “N”,
your pump is NOT a standard production model.

MAINTENANCE & REPAIR PAGE E - 1

points must be within the continuous per
formance range shown on the curve.

OM-02816 VG SERIES

SECTION DRAWING

PARTS PAGE

Figure 1. Pump Model VG5C3-B

MAINTENANCE & REPAIRPAGE E - 2

OM-02816VG SERIES

PARTS LIST

Pump Model VG5C3-B

(From S/N 1188885 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

PART NAME PART

NO.

NUMBER

MAT'L
CODE

QTY ITEM

NO.

PART NAME PART

NUMBER

MAT'L
CODE

QTY

1 PUMP CASING 26821-745 --- 1

2 IMPELLER 26821-108 --- 1
3 SEAL ASSY 25271-095 --- 1

4 DISCHARGE STICKER 6588BJ --- 1
5 SEAL PLATE GSKT 26821-426 --- 1

6 SEAL PLATE 26821-691 --- 1
7 SETSCREW 26821-942 --- 2
8 SEAL COLLAR 26821-034 --- 1

9 SHAFT SLEEVE O-RING 25154-132 --- 1
10 SHAFT SLEEVE 26821-224 --- 1
11 SEAL CAP GSKT 26821-463 --- 1

12 HEX NUT 26821-934 --- 16
13 STUD 26821-892 --- 16
14 STUD 26821-890 --- 6
15 HEX NUT 26821-933 --- 6
16 NAME PLATE 38814-043 13990 1
17 DRIVE SCREW BM#04-03 17000 2
18 HEX HD CAPSCREW 22645-162 --- 4
19 BEARING CAP 26821-074 --- 1
20 BEARING HOUSING 26821-068 --- 1
21 BEARING SPACER 26821-321 --- 1
22 RETAINING RING 26821-384 --- 1
23 ROTATION DECAL 2613M --- 1
24 LUBE DECAL 38816-079 --- 1
25 OIL INLET PLUG 26821-616 --- 1

26 OUTBRD BALL BRG 23275-012 --- 1
27 BRG CAP GSKT 26821-404 --- 1
28 OUTBRD OIL SEAL 26821-634 --- 1
29 HEX HD CAPSCREW 22645-162 --- 4
30 BEARING CAP 26821-074 --- 1
31 SHAFT KEY N0814 15990 1
32 REPAIR IMP SHAFT 26821-174 --- 1

-INCLUDES ITEMS 31, 48 AND 49

33 HEX HD CAPSCREW 22645-162 --- 2

34 FLAT WASHER K06 15991 2
35 FOOT 26821-208 --- 1
36 BEARING SPACER 26821-321 --- 1
37 BRG RETAINER RING 26821-384 --- 1
38 OIL LEVEL 26821-611 --- 1
39 PIPE PLUG P06 15079 1

40 INBRD BALL BRG S1033 --- 1
41 BRG CAP GSKT 26821-404 --- 1
42 INBRD OIL SEAL 26821-634 --- 1

43 DEFLECTOR 26821-494 --- 1
44 HEX NUT 26821-932 --- 4
45 STUD 26821-880 --- 4
46 SEAL CAP 26821-244 --- 1
47 PIPE PLUG P08 15079 1

48 IMPELLER NUT 26821-135 --- 1
49 IMPELLER KEY 26821-264 --- 1

50 SUCTION STICKER 6588AG --- 1
51 PIPE PLUG P08 15079 1

NOT SHOWN:

INSTRUCTION TAG 38817-011 --- 1
INSTRUCTION TAG 38817-024 --- 1

OPTIONAL:

NPT SUCTION FLANGE 1758 10010 1
SUCT FLANGE GSKT 1679G 18000 1
NPT DISCHARGE FLANGE 1757 10010 1
DISCH FLANGE GSKT 1678G 18000 1
STRAINER, STD S2278 --- 1
STRAINER, IRRIGATION S1529 --- 1
DISCH CHECK VLV ASSY GRP14-02A --- 1
HAND PRIMER GRP43-09 --- 1
VITON SEAL 25271-096 --- 1
BRONZE IMPELLER 26821-088 --- 1

INDICATES PARTS RECOMMENDED FOR STOCK

MAINTENANCE & REPAIR PAGE E - 3

OM-02816 VG SERIES

PUMP AND SEAL DISASSEMBLY AND REASSEMBLY

Review all SAFETY information in Section A.

Follow the instructions on all tags, label and de
cals attached to the pump.

This pump requires little service due to its rugged,
minimum‐maintenance design. However, if it be
comes necessary to inspect or replace the wearing
parts, follow these instructions which are keyed to
the sectional view (see Figure 1) and the accompa
nying parts list.

This manual will alert personnel to known proce
dures which require special attention, to those
which could damage equipment, and to those
which could be dangerous to personnel. However,
this manual cannot possibly anticipate and provide
detailed precautions for every situation that might
occur during maintenance of the unit. Therefore, it
is the responsibility of the owner/maintenance per
sonnel to ensure that only safe, established main
tenance procedures are used, and that any proce
dures not addressed in this manual are performed
only after establishing that neither personal safety
nor pump integrity are compromised by such prac
tices.

Before attempting to service the pump, disconnect
or lock out the power source and take precautions
to ensure that it will remain inoperative. Close all
valves in the suction and discharge lines.

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.

Impeller Removal

For access to the impeller (2) or seal assembly (3),
the pump casing (1) must be separated from the
seal plate (6).

Drain the suction and discharge piping and re
move it from the pump. Remove the casing drain
plug (47) and drain the pump. Clean and reinstall
the drain plug.

Before attempting to open or service the
pump:

1. Familiarize yourself with this man
ual.

2. Disconnect or lock out 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.

Remove the hardware securing the pump casing
to the base. Wedge a block of wood under the
bearing housing (20) to support the housing when
the casing is removed.

Remove the nuts (12) and separate the pump cas
ing from the seal plate. Tie and tag any leveling
shims used under the casing mounting feet. Re
move the seal plate gasket (5) and clean the mat
ing surfaces.

Immobilize the shaft (32). Remove the impeller nut
(48) and use a soft‐faced mallet to tap the impeller
from the shaft. Retain the impeller key (49). Inspect
the impeller and replace it if cracked or badly worn.

MAINTENANCE & REPAIRPAGE E - 4

OM-02816VG SERIES

Seal Removal

To remove the seal assembly (3), disengage the
nuts (15) and slide the seal plate (6), seal cap (46),
seal and shaft sleeve (10) off the shaft as a single
unit. Remove the shaft sleeve O‐ring (9).

Disengage the nuts (44) and remove the seal cap
(46) and gasket (11). Remove the stationary ele
ment and O‐ring from the seal cap.

Pull the sleeve and rotating portion of the seal from
the seal plate. Apply oil to the sleeve and work it up
under the bellows. Slide the rotating element, re
tainer and bellows, spring, and spring holder off
the sleeve.

NOTE

It is not necessary to remove the seal collar (8) un
less the collar or sleeve requires replacement. DO
NOT remove the collar until the exact location has
been recorded either by scribing or measurement.
The location of the collar is critical to pump opera
tion since it establishes the working length of the
seal. After the dimension has been recorded, or the
location scribed, loosen the setscrews (7) and
slide the collar off the sleeve.

Remove the hardware securing the foot (35) to the
base, and move the bearing housing to a clean,
well‐equipped shop for disassembly.

Remove the drain plug (39) and drain the bearing
housing. Clean and reinstall the drain plug.

Disengage the hardware (18 and 29) and remove
the inboard and outboard bearing covers (19 and

30) and gaskets (27 and 41). Inspect the oil seals
(28 and 42) and, if replacement is required, use a
screwdriver or other suitable tool to pry them from
the bearing covers.

Place a block of wood against the drive end of the
shaft and tap the shaft and assembled bearings
(26 and 40) out of the bearing housing.

After removing the shaft and bearings, clean and
inspect the bearings in place as follows.

To prevent damage during removal from
the shaft, it is recommended that bearings
be cleaned and inspected in place. It is
strongly recommended that the bearings
be replaced any time the shaft and bear
ings are removed.

If no further disassembly is required, see Seal In

stallation.

Shaft And Bearing Removal And Disassembly

When the pump is properly operated and main
tained, the bearing housing should not require dis
assembly. Disassemble the shaft and bearings
only when there is evidence of wear or damage.

Shaft and bearing disassembly in the field
is not recommended. These operations
should be performed only in a properly‐
equipped shop by qualified personnel.

Separate the power source from the shaft (32) and
remove the deflector (43) and key (31).

Clean the bearing housing, shaft and all compo
nent parts (except the bearings) with a soft cloth
soaked in cleaning solvent. Inspect the parts for
wear or damage and replace as necessary.

Most cleaning solvents are toxic and
flammable. Use them only in a well ven
tilated area free from excessive heat,
sparks, and flame. Read and follow all
precautions printed on solvent contain
ers.

Clean the bearings thoroughly in fresh cleaning
solvent. Dry the bearings with filtered compressed
air and coat with light oil.

Bearings must be kept free of all dirt and

MAINTENANCE & REPAIR PAGE E - 5

OM-02816 VG SERIES

foreign material. Failure to do so will great
ly shorten bearing life. Do not spin dry
bearings. This may scratch the balls or
races and cause premature bearing fail
ure.

Rotate the bearings by hand to check for rough
ness or binding and inspect the bearing balls. If ro
tation is rough or the bearing balls are discolored,
replace the bearings.

The bearing tolerances provide a tight press fit
onto the shaft and a snug slip fit into the bearing
housing. Replace the bearings, shaft, or bearing
housing if the proper bearing fit is not achieved.

Use a bearing puller to remove the inboard and
outboard bearings from the shaft. Remove the
bearing spacers (21 and 36).

It is not necessary to remove the bearing snap
rings (22 and 37) from the shaft unless replace
ment is required. If replacement is required, use
snap ring pliers to remove the snap rings from the
impeller shaft.

NOTE

If a hot oil bath is used to heat the bearings, both the
oil and the container must be absolutely clean. If
the oil has been previously used, it must be thor
oughly filtered.

Heat the bearings to a uniform temperature no
higher than 250F (120C), and slide the bearings

onto the shaft, one at a time, until they are fully
seated against the bearing spacers. This should
be done quickly, in one continuous motion, to pre
vent the bearings from cooling and sticking on the
shaft.

Use caution when handling hot bear
ings to prevent burns.

After the bearings have been installed and allowed
to cool, check to ensure that they have not moved
out of position in shrinking. If movement has oc
curred, use a suitable sized sleeve and a press to
reposition the bearings.

Shaft And Bearing Reassembly
And Installation

If removed, reinstall the bearing snap rings (22 and

37) in the grooves in the shaft. Replace the bearing
spacers (21 and 36).

Clean and inspect the bearings as indicated in
Shaft and Bearing Removal and Disassembly.

To prevent damage during removal from
the shaft, it is recommended that bearings
be cleaned and inspected in place. It is
strongly recommended that the bearings
be replaced any time the shaft and bear
ings are removed.

The bearings may be heated to ease installation.
An induction heater, hot oil bath, electric oven, or
hot plate may be used to heat the bearings. Bear
ings should never be heated with a direct flame or
directly on a hot plate.

If heating the bearings is not practical, use a suit
able sized sleeve and an arbor (or hydraulic) press
to install the bearings on the shaft.

When installing the bearings onto the
shaft, never press or hit against the outer
race, balls, or ball cage. Press only on the
inner race.

Install the oil seal (28) in the outboard bearing
cover (30). Install the gasket (27), and secure the
bearing cover to the bearing housing (20) with the
capscrews (29).

Slide the shaft and assembled bearings into the
bearing housing until the outboard bearing seats
against the bearing cover. Be careful not to dam
age the lip of the oil seal (28) on the shaft keyway.

When installing the shaft and bearings into

MAINTENANCE & REPAIRPAGE E - 6

OM-02816VG SERIES

the bearing bore, push against the outer
race. Never hit the balls or ball cage.

Install the inboard oil seal (42) in the bearing cover
(19). Slide the inboard bearing cover and gasket
(41) over the shaft and secure them with the cap
screws (18). Be careful not to damage the oil seal
on the shaft threads.

Install the deflector (43) and shaft key (31).

If removed, secure the foot (35) to the bearing
housing with the hardware (33 and 34), and sup
port the bearing housing with a wood block until
the pump is fully reassembled. Lubricate the bear
ings as indicated in LUBRICATION.

Seal Reassembly and Installation

Clean the seal cavity and shaft with a cloth soaked
in fresh cleaning solvent.

Most cleaning solvents are toxic and
flammable. Use them only in a well ven
tilated area free from excessive heat,
sparks, and flame. Read and follow all
precautions printed on solvent contain
ers.

The seal is not normally reused because wear pat
terns on the finished faces cannot be realigned
during reassembly. This could result in premature
failure. If necessary to reuse an old seal in an emer
gency, carefully wash all metallic parts in fresh
cleaning solvent and allow to dry thoroughly.

Handle the seal parts with extreme care to prevent
damage. Be careful not to contaminate precision
finished faces; even fingerprints on the faces can
shorten seal life. If necessary, clean the faces with a
non‐oil based solvent and a clean, lint‐free tissue.
Wipe lightly in a concentric pattern to avoid
scratching the faces.

Inspect the seal components for wear, scoring,
grooves, and other damage that might cause leak
age. Clean and polish the shaft sleeve, or replace it
if there are nicks or cuts on either end. If any com
ponents are worn, replace the complete seal;
never mix old and new seal parts.

If a replacement seal is being used, remove it from
the container and inspect the precision finished
faces to ensure that they are free of any foreign
matter.

To ease installation of the seal, lubricate the shaft
sleeve, O‐rings and bellows with water or a very
small amount of oil, and apply a drop of light lubri
cating oil on the finished faces. Assemble the seal
as follows, (see Figure 2).

MAINTENANCE & REPAIR PAGE E - 7

OM-02816 VG SERIES

RETAINER

SPRING CENTERING

WASHER

SPRING

SHAFT SLEEVE

O‐RING

SEAL

COLLAR

SETSCREW

SEAL PLATE

A

BELLOWS

O‐RING

STATIONARY

ELEMENT

IMPELLER SHAFT

SEAL CAP

ROTATING

ELEMENT

Figure 2. 25271-095 Seal Assembly

This seal is not designed for operation at
temperatures above 160F (71C). Do not
use at higher operating temperatures.

Locate the collar (8) on the shaft sleeve at the
scribed mark or dimension taken before disassem
bly, and secure with the setscrews (7).

NOTE

If the dimension is not known, slide the sleeve onto
the shaft until fully seated, and scribe the seal work
ing length on the shaft (dimension “A” shown in Fig
ure 2). The designed working length (from the sta
tionary seal face to the collar) for this seal is 2-3/8
inches (60,2 mm). Secure the collar on the sleeve at
this point with the setscrews.

Slide the spring holder and spring over the sleeve
and against the collar. Assemble the drive grooves
of rotating element into the drive lugs of the bellows
retainer, and slide this rotating portion of the seal
over the sleeve until the retainer seats in the spring.

Use thumb pressure to press the stationary seat
and O‐ring into the seal cap (46) until fully seated.
Slide the assembled stationary seat, seal cap and
gasket over the shaft sleeve until the seal faces
contact and secure the seal cap and gasket (11) to
the seal plate (6) with the nuts (44).

Install the sleeve O‐ring (9) completely against the
shaft shoulder. Be careful not to cut it on the impel
ler keyway.

Slide the seal plate, shaft sleeve and seal assembly
onto the shaft. Secure the seal plate to the bearing
housing with the nuts (15).

Impeller Installation

Position the seal plate on a flat surface with the im
peller side down. Position the sleeve in the seal
plate bore with the chamfered end facing up.

Inspect the impeller, and replace it if cracked or
badly worn. Install the impeller key (49) and slide
the impeller onto the shaft and against the sleeve

MAINTENANCE & REPAIRPAGE E - 8

OM-02816VG SERIES

until both are fully seated. Install the impeller nut
(48).

Install the seal plate gasket (5). Slide the pump
casing (1) over the impeller and secure it to the seal
plate with the nuts (12).

Replace any leveling shims used under the casing
mounting feet and install the hardware securing
the casing and bearing housing foot to the base.
Remove the wood block supporting the bearing
housing.

Final Pump Assembly

Be sure the pump is secure to the base and power

source.

Install the suction and discharge lines and open all
valves. Make certain that all piping connections are
tight, properly supported and secure.

Be sure the pump and power source have been
properly lubricated, see LUBRICATION.

Fill the pump casing with clean liquid. Reinstall the
fill plug (51) and tighten it. Refer to OPERATION,
Section C, before putting the pump back into serv
ice.

LUBRICATION

Bearings

The bearing housing was fully lubricated when
shipped from the factory. Check the oil level regu
larly through the sight gauge (38) and maintain it at
the middle of the gauge. When lubrication is re
quired, add SAE No. 30 non‐detergent oil through
the oil inlet plug opening (25). Do not over‐lubri
cate. Over‐lubrication can cause the bearings to
over‐heat, resulting in premature bearing failure.

Under normal conditions, drain the bearing hous
ing once each year and refill with clean oil. Change
the oil more frequently if the pump is operated con
tinuously or installed in an environment with rapid
temperature change.

Monitor the condition of the bearing lubri
cant regularly for evidence of rust or mois
ture condensation. This is especially im
portant in areas where variable hot and
cold temperatures are common.

For cold weather operation, consult the factory or a
lubricant supplier for the recommended grade of
oil.

Seal Assembly

The seal assembly is lubricated by the medium be
ing pumped and no additional lubrication is re
quired.

MAINTENANCE & REPAIR PAGE E - 9

Power Source

Consult the literature supplied with the power
source, or contact your local power source repre
sentative.

For U.S. and International Warranty Information,

Please Visit www.grpumps.com/warranty

or call:

U.S.: 419-755-1280

International: [phone]

For Canadian Warranty Information,

Please Visit www.grcanada.com/warranty

or call:

519-631-2870

THE GORMAN‐RUPP COMPANY  MANSFIELD, OHIO

GORMAN‐RUPP OF CANADA LIMITED  ST. THOMAS, ONTARIO, CANADA