GORMAN-RUPP PUMPS CE Series User manual

April 6, 2000
Rev. B 04/16/01
OM-03909-OE02
ACE
THE GORMAN-RUPP COMPANY MANSFIELD, OHIO
GORMAN-RUPP OF CANADA LIMITED ST. THOMAS, ONTARIO, CANADA Printed in U.S.A.
Copyright by the Gorman-Rupp Company
INSTALLATION, OPERATION,
AND MAINTENANCE MANUAL
WITH PARTS LIST
CE SERIES PUMP
MODEL
CE6A60−(SAE 4/10)

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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Alignment PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mounting PAGE B − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clearance 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 − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strainers PAGE B − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sealing PAGE B − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Suction Lines In Sumps PAGE B − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Suction Line Positioning PAGE B − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DISCHARGE LINES PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Siphoning PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valves PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bypass Lines PAGE B − 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AUTOMATIC AIR RELEASE VALVE PAGE B − 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Theory of Operation PAGE B − 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Release Valve Installation PAGE B − 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OPERATION − SECTION C PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PRIMING PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
STARTING PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OPERATION PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lines With a Bypass PAGE C − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lines Without a Bypass PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Leakage PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Liquid Temperature And Overheating PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Strainer Check PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pump Vacuum Check PAGE C − 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
STOPPING PAGE C − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cold Weather Preservation PAGE C − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
BEARING TEMPERATURE CHECK PAGE C − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING − SECTION D PAGE D − 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PUMP MAINTENANCE AND REPAIR - SECTION E PAGE E − 1. . . . . . . . . . . . . . . . .
PARTS LISTS:
Pump End Assy PAGE E − 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TABLE OF CONTENTS
(continued)
ii
Rotating Assy PAGE E − 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Drive Assembly PAGE E − 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PUMP AND SEAL DISASSEMBLY AND REASSEMBLY PAGE E − 8. . . . . . . . . . . . . . . . . . . . . . . . .
Back Cover And Wear Plate Removal PAGE E − 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Suction Check Valve Removal PAGE E − 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Separating Intermediate And Drive Assembly From Engine PAGE E − 9. . . . . . . . . . . . . . . . . .
Loosening Impeller PAGE E − 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rotating Assembly Removal PAGE E − 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Impeller Removal PAGE E − 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seal Removal PAGE E − 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shaft and Bearing Removal and Disassembly PAGE E − 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shaft and Bearing Reassembly and Installation PAGE E − 11. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seal Reassembly and Installation PAGE E − 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Impeller Installation And Adjustment PAGE E − 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rotating Assembly Installation PAGE E − 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Securing Intermediate And Drive Assembly To Engine PAGE E − 15. . . . . . . . . . . . . . . . . . . . . .
Suction Check Valve Installation PAGE E − 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Back Cover Installation PAGE E − 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PRESSURE RELIEF VALVE MAINTENANCE PAGE E − 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Final Pump Assembly PAGE E − 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LUBRICATION PAGE E − 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seal Assembly PAGE E − 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bearings PAGE E − 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine PAGE E − 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CE SERIES OM−03909
PAGE I − 1INTRODUCTION
INTRODUCTION
This Installation, Operation, and Maintenance
manual is designed to help you achieve the best
performance and longest life from your Gorman-
Rupp pump.
This pump is a CE Series, semi-open impeller, self-
priming centrifugal model with a suction check
valve. The pump is designed to be close-coupled
to any engine with an SAE 4 bellhousing and a
10-inch over-the-center clutch. Gorman-Rupp has
no control over or particular knowledge of the en-
gine which will be used. Refer to the manual ac-
companying the engine before installing or operat-
ing the pump.
The pump is designed for handling dirty water con-
taining specified entrained solids. The basic mate-
rial of construction is gray iron, with ductile iron im-
peller and steel wearing parts.
If there are any questions regarding the pump or its application which are not covered in this manual or in
other literature accompanying this unit, please contact your Gorman-Rupp distributor, or write:
The Gorman-Rupp Company or Gorman-Rupp of Canada Limited
P.O. Box 1217 70 Burwell Road
Mansfield, Ohio 44901−1217 St. Thomas, Ontario N5P 3R7
For information or technical assistance on the engine, contact the engine manufacturer’s local dealer or
representative.
The following are used to alert maintenance personnel to procedures which require special attention, to
those which could damage equipment, and to those which could be dangerous to personnel:
Immediate hazards which WILL result in
severe personal injury or death. These
instructions describe the procedure re-
quired and the injury which will result
from failure to follow the procedure.
Hazards or unsafe practices which
COULD result in severe personal injury
or death. These instructions describe
the procedure required and the injury
which could result from failure to follow
the procedure.
Hazards or unsafe practices which COULD
result in minor personal injury or product
or property damage. These instructions
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.

CE SERIES OM−03909
PAGE A − 1SAFETY
SAFETY - SECTION A
This information applies to CE Series
engine driven pumps. Gorman-Rupp
has no control over or particular knowl-
edge of the engine which will be used.
Refer to the manual accompanying the
engine before attempting to begin oper-
ation.
Before attempting to open or service the
pump:
1. Familiarize yourself with this man-
ual.
2. Shut down the engine and take
precautions 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 dirty
water containing specified entrained
solids. Do not attempt to pump volatile,
corrosive, or flammable liquids which
may damage the pump or endanger per-
sonnel as a result of pump failure.
Use lifting and moving equipment in
good repair and with adequate capacity
to prevent injuries to personnel or dam-
age to equipment. Suction and dis-
charge hoses and piping must be re-
moved from the pump before lifting.
After the pump has been installed, make
certain that the pump and all piping or
hose connections are tight, properly
supported and secure before operation.
Do not operate the pump against a
closed discharge valve 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.
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 cool before servicing.
Do not operate an internal combustion
engine in an explosive atmosphere.
When operating internal combustion
engines in an enclosed area, make cer-
tain that exhaust fumes are piped to the
outside. These fumes contain carbon
monoxide, a deadly gas that is color-
less, tasteless, and odorless.

CE SERIESOM−03909
PAGE A − 2 SAFETY
Fuel used by internal combustion en-
gines presents an extreme explosion
and fire hazard. Make certain that all
fuel lines are securely connected and
free of leaks. Never refuel a hot or run-
ning engine. Avoid overfilling the fuel
tank. Always use the correct type of fuel.

CE SERIES OM−03909
PAGE B − 1INSTALLATION
INSTALLATION − SECTION B
Review all SAFETY information in Section A.
Since pump installations are seldom identical, this
section offers only general recommendations and
practices required to inspect, position, and ar-
range the pump and piping.
Most of the information pertains to a standard
static lift application where the pump is positioned
above the free level of liquid to be pumped.
If installed in a flooded suction application where
the liquid is supplied to the pump under pressure,
some of the information such as mounting, line
configuration, and priming must be tailored to the
specific application. Since the pressure supplied
to the pump is critical to performance and safety,
be sure to limit the incoming pressure to 50% of the
maximum permissible operating pressure.
For further assistance, contact your Gorman-Rupp
distributor or the Gorman-Rupp Company.
PREINSTALLATION INSPECTION
The pump assembly was inspected and tested be-
fore shipment from the factory. Before installation,
inspect the pump for damage which may have oc-
curred during shipment. Check as follows:
a. Inspect the pump assembly for cracks, dents,
damaged threads, and other obvious dam-
age.
b. Check for and tighten loose attaching hard-
ware. Since gaskets tend to shrink after dry-
ing, check for loose hardware at mating sur-
faces.
c. Carefully read all tags, decals, and markings
on the pump assembly, and perform all duties
indicated.
d. Check levels and lubricate as necessary. Re-
fer to LUBRICATION in the MAINTENANCE
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
Use lifting and moving equipment in
good repair and with adequate capacity
to prevent injuries to personnel or dam-
age to equipment. Suction and dis-
charge hoses and piping must be re-
moved from the pump before lifting.
Lifting
Use lifting equipment with a capacity of at least
4,500 pounds (2041 kg). This pump weighs ap-
proximately 880 pounds (399 kg), not including
the weight of the engine, any accessories, or cus-
tomer installed options. Customer installed equip-
ment such as suction and discharge piping must
be removed before attempting to lift.
The pump assembly can be seriously
damaged if the cables or chains used to lift
and move the unit are improperly wrapped
around the pump.
After mounting the pump end to the engine and
base, use lifting equipment with a capacity of at
least 5 times the weight of the complete unit.

OM−03909 CE SERIES
PAGE B − 2 INSTALLATION
Alignment
The alignment of the pump end and the engine is
critical for trouble-free mechanical operation. Dur-
ing initial installation of the pump end, refer to Se-
curing Intermediate And Drive Assembly To En-
gine in MAINTENANCE AND REPAIR, Section E
for details.
Mounting
Locate the pump in an accessible place as close as
practical to the liquid being pumped. Level mount-
ing is essential for proper operation.
The pump may have to be supported or shimmed
to provide for level operation or to eliminate vibra-
tion.
If the pump has been mounted on a moveable
base, make certain the base is stationary by setting
the brake and blocking the wheels before attempt-
ing to operate the pump.
To ensure sufficient lubrication and fuel supply to
the engine, do not position the pump and engine
more than 15off horizontal for continuous opera-
tion. The pump and engine may be positioned up
to 30off horizontal for intermittent operation
only; however, the engine manufacturer should be
consulted for continuous operation at angles
greater than 15.
Clearance
When positioning the pump, allow a minimum
clearance of 18 inches (457,2 mm) in front of the
back cover to permit removal of the cover and easy
access to the pump interior.
SUCTION AND DISCHARGE PIPING
Pump performance is adversely effected by in-
creased suction lift, discharge elevation, and fric-
tion losses. Contact the factory to be sure your
overall application allows the pump to operate
within the safe operation range.
Materials
Either pipe or hose maybe used for suction and
discharge lines; however, the materials must be
compatible with the liquid being pumped. If hose is
used in suction lines, it must be the rigid-wall, rein-
forced type to prevent collapse under suction. Us-
ing piping couplings in suction lines is not recom-
mended.
Line Configuration
Keep suction and discharge lines as straight as
possible to minimize friction losses. Make mini-
mum use of elbows and fittings, which substan-
tially increase friction loss. If elbows are necessary,
use the long-radius type to minimize friction loss.
Connections to Pump
Before tightening a connecting flange, align it ex-
actly with the pump port. Never pull a pipe line into
place by tightening the flange bolts and/or cou-
plings.
Lines near the pump must be independently sup-
ported to avoid strain on the pump which could
cause excessive vibration, decreased bearing life,
and increased shaft and seal wear. If hose-type
lines are used, they should have adequate support
to secure them when filled with liquid and under
pressure.
Gauges
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. 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.

CE SERIES OM−03909
PAGE B − 3INSTALLATION
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.
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-inch (76,2
mm) diameter spherical solids.
Sealing
Since even a slight leak will affect priming, head,
and capacity, especially when operating with a
high suction lift, all connections in the suction line
should be sealed with pipe dope to ensure an air-
tight seal. Follow the sealant manufacturer’s rec-
ommendations when selecting and applying the
pipe dope. The pipe dope should be compatible
with the liquid being pumped.
Suction Lines In Sumps
If a single suction line is installed in a sump, it
should be positioned away from the wall of the
sump at a distance equal to 1 1/2 times the diame-
ter of the suction line.
If there is a liquid flow from an open pipe into the
sump, the flow should be kept away from the suc-
tion inlet because the inflow will carry air down into
the sump, and air entering the suction line will re-
duce pump efficiency.
If it is necessary to position inflow close to the suc-
tion inlet, install a baffle between the inflow and the
suction inlet at a distance 1-1/2 times the diameter
of the suction pipe. The baffle will allow entrained
air to escape from the liquid before it is drawn into
the suction inlet.
If two suction lines are installed in a single sump,
the flow paths may interact, reducing the efficiency
of one or both pumps. To avoid this, position the
suction inlets so that they are separated by a dis-
tance equal to at least 3 times the diameter of the
suction pipe.
Suction Line Positioning
The depth of submergence of the suction line is
critical to efficient pump operation. Figure 1 shows
recommended minimum submergence vs. veloc-
ity.
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).

OM−03909 CE SERIES
PAGE B − 4 INSTALLATION
Figure 1. 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-
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.
Bypass Lines
Self-priming pumps are not air compressors. Dur-
ing the priming cycle, air from the suction line must
be vented to atmosphere on the discharge side. If
the discharge line is open, this air will be vented
through the discharge. However, if a check valve
has been installed in the discharge line, the dis-
charge side of the pump must be opened to atmos-
pheric pressure through a bypass line installed be-
tween the pump discharge and the check valve. A
self-priming centrifugal pump will not prime if
there is sufficient static liquid head to hold the dis-
charge check valve closed.
NOTE
The bypass line should be sized so that it does not
affect pump discharge capacity; however, the by-