Dover WILDEN PSG T20 Instruction Manual

EOM
ENGINEERING OPERATION
& MAINTENANCE
T20 Clamped
Metal Pump
WIL-10280-E-04
Where InnovationFlows

WIL-10280-E-04 Wilden®
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Contents
Section 1: Precautions - Read First! 4
Section 2: Wilden Pump Designation System 5
Section 3: How It Works 6
Section 4: Dimensional Drawings 7
Section 5: Performance 8
T20 M etal Food G rade/Polyuretha ne -Fitt ed 8
T20 Metal FK M ®/PTFE-F itt ed 8
T20 Metal Wi l- F le x™ /Po ly ur eth ane -Fitted 9
Su ct ion- Li ft Capab i l it y 10
Section 6: Suggested Installation, Operation, 11
Maintenance and Troubleshooting
Section 7: Disassembly / Reassembly 14
Pu mp Di sa ssembly 14
In l et Ho us ing Disas s em bly 15
Ce n ter Se c tio n Ho u sing Disassem b l y 16
Di sc harge Housi ng Disassembl y 21
Pu mp Bo dy Dis a s se m bly 22
Ai r Va lv e D is assembl y 23
Section 8: Exploded View and Parts List 27
T20 Or i gin al TM M e t al 27
Section 9: Elastomer Options 29

WIL-10280-E-04 Wilden®
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Copyright
Copyright 2018 PSG®, a Dover Company. All rights reserved.
PSG reserves the right to modify the information and illustrations in this document without prior notice. The
product described in this document is furnished under a license agreement or nondisclosure agreement. No
part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or any
means electronic or mechanical, including photocopying and recording, without the written permission of PSG,
a Dover Company, except as described by the terms of those agreements.
This is a non-contractual document. 01-2019.
Trademarks
PSG and the PSG logo are registered trademarks of PSG. Wilden® is a registered trademark of PSG
California LLC. Pro-Flo® SHIFT and Pro-Flo® are registered trademarks of PSG California LLC. Wil-Flex® is a
trademark of PSG California LLC. Saniflex™ is a trademark of PSG California LLC.
All trademarks, names, logos and service marks (collectively "trademarks") in this document are registered
and unregistered trademarks of their respective owners. Nothing contained in this document should be
construed as granting any license or right to use any trademark without the prior written permission of the
trademark owner.
Warranty
Each and every product manufactured by Wilden is built to meet the highest standards of quality. Every pump
is functionally tested to insure integrity of operation. Wilden warrants that pumps, accessories and parts
manufactured or supplied by it to be free from defects in material and workmanship for a period of five (5)
years from date of installation or six (6) years from date of manufacture, whichever comes first.
For more information, and to register your Wilden pump for warranty, please visit
https://www.psgdover.com/wilden/support/warranty-registration.
Certifications

WIL-10280-E-04 Wilden®
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Precautions - Read First!
TEMPERATURE LIMITS:
Neoprene
0°F to 200°F
–17.8°C to 93.3°C
Buna-N
+10°F to +180°F
–12.2°C to 82.2°C
EPDM
–60°F to 280°F
–51.1°C to 137.8°C
FKM®
–40°F to +350°F
–40°C to 176.7°C
Wil-Flex™
–40°F to +225°F
–40°C to 107.2°C
Polyurethane
10°F to 150°F
12.2°C to 65.6°C
Saniflex™
–20°F to 220°F
–28.9°C to 104.4°C
PTFE
40°F to +220°F
4.4°C to 104.4°C
Fluoro-Seal™
–40°F to +450°F
–40°C to 232°C
NOTE: Not all materials are available for all models. See "Wilden Pump
Designation System " on page 5 for material options for your pump.
WARNING: Possible explosion can result from Halogenated
Hydrocarbon solvents when used in pressurized fluid
systems having aluminum or galvanized wetted parts.
CAUTION: Do not exceed 125 psig air supply pressure.
(50 psig on UL models.).
CAUTION: Always wear safety glasses when operating
pump. When diaphragm rupture occurs, material being
pumped may be forced out air exhaust.
NOTE: Pump must be lubricated. Wilden suggests an
arctic 5 weight oil (ISO grade 15).
WARNING: Prevention of static sparking —If static
sparking occurs, fire or explosion could result. Pump,
valves, and containers must be grounded when
handling flammable fluids and whenever discharge of
static electricity is a hazard.
CAUTION: Do not exceed 125 psig air supply pressure.
Blow out air line for 10 to 20 seconds before attaching
to pump to make sure all pipe line debris is clear.
Always use an in-line filter.
CAUTION: Before any maintenance or repair is
attempted, the compressed air line to the pump should
be disconnected and all air pressure allowed to bleed
from pump. Disconnect all intake, discharge and air
lines.
NOTE: Before starting disassembly, mark a line from
each liquid chamber to its corresponding air chamber,
as well as a line from the liquid chamber to its
corresponding discharge elbow and ball pot. These lines
will assist in proper alignment during reassembly.
CAUTION: When removing the end cap using compressed
air, the air valve end cap may come out with considerable
force. Hand protection such as a padded glove or a rag
should be used to capture the end cap.
NOTE: All non-lube-free air-operated pumps must
be lubricated. Wilden suggests an arctic weight oil
(ISO grade 15).
CAUTION: When choosing pump materials, be
sure to check the temperature limits for all wetted
components. Example: FKM®has a maximum limit
of 176.7°C (350°F) but polypropylene has a maximum
limit of only 79°C (175°F).
WARNING: Tighten all clamp bands prior to installation.
Fixing bolts may loosen during transportation.
CAUTION: Verify the chemical compatibility of the process
and cleaning fluid to the pump’s component materials in
the Chemical Resistance Guide (see E4).
CAUTION: Only explosion proof (NEMA 7) solenoid valves
should be used in areas where explosion proof equipment
is required
CAUTION: Maximum temperature limits are based upon
mechanical stress only. Certain chemicals will
significantly reduce maximum safe operating
temperatures. Consult engineering guide for chemical
compatibility and temperature limits.
CAUTION: When choosing pump materials, be sure to check
the temperature limits for all wetted components. Example:
FKM has a maximum limit of 176.7°C (350°F) but
polypropylene has a maximum limit of only 79°C (175°F).
Section 1

WIL-10280-E-04 Wilden®
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LEGEND
T20 METAL
102 mm (4") Pump
Maximum Flow Rate:
1,041 lpm (275 gpm)
T20
/
X
X
X
X
X
/
XXX
/
XX
/
X
XX
/
XXXX
O-RINGS
MODEL
VALVE SEAT
VALVE BALLS
SPECIALTY CODE
DIAPHRAGMS
(if applicable)
AIR VALVE
CENTER BLOCK
AIR CHAMBERS
OUTER PISTON
WETTED PATHS
Section 2
WILDEN PUMP DESIGNATION SYSTEM

WIL-10280-E-04 Wilden®
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The Wilden diaphragm pump is an air-operated, positive displacement, self-priming pump. These drawings show the flow
pattern through the pump upon its initial stroke. It is assumed the pump has no fluid in it prior to its initial stroke.
FIGURE1 The air valve directs pressurized
air to the back side of diaphragm A. The
compressed air is applied directly to the
liquid column separated by elastomeric
diaphragms. The diaphragm acts as a
separation membrane between the
compressed air and liquid, balancing the
load and removing mechanical stress from
the diaphragm. The compressed air moves
the diaphragm away from the center block
of the pump. The opposite diaphragm is
pulled in by the shaft connected to the
pressurized diaphragm. Diaphragm B is on
its suction stroke; air behind the diaphragm
has been forced out to the atmosphere
through the exhaust port of the pump. The
movement of diaphragm B toward the
center block of the pump creates a vacuum
within chamber B. Atmospheric pressure
forces fluid into the inlet manifold forcing the
inlet valve ball off its seat. Liquid is free to
move past the inlet valve ball and fill the
liquid chamber (see shaded area).
FIGURE 2 When the pressurized
diaphragm, diaphragm A, reaches the limit of
its discharge stroke, the air valve redirects
pressurizedairto theback side of diaphragm
B. The pressurized air forces diaphragm B
away from the center block while pulling
diaphragm A to the center block. Diaphragm
B is now on its discharge stroke. Diaphragm
B forces the inlet valve ball onto its seat due
tothe hydraulic forcesdeveloped in the liquid
chamber and manifold of the pump. These
same hydraulic forces liftthe discharge valve
ball off its seat, while the opposite discharge
valve ball is forced onto its seat, forcing fluid
to flow through the pump discharge. The
movement of diaphragm A toward the center
block of the pump creates a vacuum within
liquid chamber A. Atmospheric pressure
forces fluid into the inlet manifold of the
pump.Theinletvalveballisforcedoffitsseat
allowing the fluid being pumped to fill the
liquid chamber.
FIGURE 3 At completion of the stroke, the
air valve again redirects air to the back side
of diaphragm A, which starts diaphragm B
on its exhaust stroke. As the pump reaches
its original starting point, each diaphragm
has gone through one exhaust and one
discharge stroke. This constitutes one
complete pumping cycle. The pump may
take several cycles to completely prime
depending on the conditions of the
application .
Section 3
HOW IT WORKS —PUMP

WIL-10280-E-04 Wilden®
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T20 Metal
DIMENSIONS
ITEM
METRIC (mm)
STANDARD (inch)
A
950
37.4
B
119
4.7
C
680
26.8
D
826
32.5
E
330
13.0
F
439
17.3
G
155
6.1
H
168
6.6
J
424
16.7
K
333
13.1
L
279
11.0
M
455
17.9
N
376
14.8
P
15 DIA.
.6 DIA.
R
231
9.1
S
191
7.5
T
18 DIA.
.7 DIA.
Rev. B
DIMENSIONAL DRAWING
Section 4

WIL-10280-E-04 Wilden®
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PERFORMANCE
T20 METAL
Rubber-Fitted
Height............................ 826 mm (32.5")
Width ............................. 940 mm (37.0")
Depth............................. 330 mm (13.0")
Est. ShipWeight .. Cast Iron 231 kg (500 lbs)
Air Inlet..................................19 mm (3/4")
Inlet..................................... 102 mm (4")
Outlet .................................... 102 mm (4")
Suction Lift.................... 12' Dry (3.66 m)
30' Wet (9.14 m)
Disp.PerStroke
1
.................1.22 gal. (4.62 l)
Max.FlowRate........1041 lpm (275 gpm)
Max. Size Solids.................35 mm (1-3/8")
1
Displacement per stroke was calculated
at 70 psig air inlet pressure against
a 30 psig head pressure.
Example: To pump 140 gpm against
a discharge head of 20 psig requires
40 psig and 75 scfm air consumption.
(See dot on curve.)
Volumes indicated on chart were determined by actually pumping water.
For optimum life and performance, pumps should be specified so that daily
operation parameters will fall in the center of the pump performance curve.
T20 METAL
Rubber-Fitted
Height............................ 826 mm (32.5")
Width ............................. 940 mm (37.0")
Depth............................. 330 mm (13.0")
Est. ShipWeight .. Cast Iron 231 kg (500 lbs)
Air Inlet..................................19 mm (3/4")
Inlet.....................................102 mm (4")
Outlet .................................... 102 mm (4")
Suction Lift.................... 12' Dry (3.66 m)
30' Wet (9.14 m)
Disp.PerStroke
1
.................1.22 gal. (4.62 l)
Max.FlowRate........1041 lpm (275 gpm)
Max. Size Solids.................35 mm (1-3/8")
1
Displacement per stroke was calculated
at 70 psig air inlet pressure against
a 30 psig head pressure.
Example: To pump 140 gpm against
a discharge head of 20 psig requires
40 psig and 75 scfm air consumption.
(See dot on curve.)
Section 5
Volumes indicated on chart were determined by actually pumping water.
For optimum life and performance, pumps should be specified so that daily
operation parameters will fall in the center of the pump performance curve
T20 Metal FKM / PTFE-Fitted

WIL-10280-E-04 Wilden®
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PERFORMANCE
T20 METAL
Wil-Flex™
Polyurethane-Fitted
Height............................ 826 mm (32.5")
Width ............................. 940 mm (37.0")
Depth............................. 330 mm (13.0")
Est. ShipWeight .. Cast Iron 231 kg (500 lbs)
Air Inlet..................................19 mm (3/4")
Inlet..................................... 102 mm (4")
Outlet .................................... 102 mm (4")
Suction Lift.................... 12' Dry (3.66 m)
30' Wet (9.14 m)
Disp.PerStroke
1
.................1.22 gal. (4.62 l)
Max.FlowRate........1041 lpm (275 gpm)
Max. Size Solids.................35 mm (1-3/8")
1
Displacement per stroke was calculated
at 70 psig air inlet pressure against
a 30 psig head pressure.
Example: To pump 140 gpm against
a discharge head of 20 psig requires
40 psig and 75 scfm air consumption.
(See dot on curve.)
Volumes indicated on chart were determined by actually pumping water.
For optimum life and performance, pumps should be specified so that daily
operation parameters will fall in the center of the pump performance curve.

WIL-10280-E-04 Wilden®
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Suggested Installation, Operation, Maintenance and Troubleshooting
The Model T20 has a 102 mm (4") inlet and 102 mm (4") outlet and is designed
for flows to 1041 lpm (275 gpm). The T20 pump is manufactured with wetted
parts of Cast Iron. The center block of the T20 is constructed of die cast
aluminum. A variety of diaphragms, valve balls, and o-rings are available to
satisfy temperature, chemical compatibility, abrasion and flex concerns.
The suction pipe size should be at least 102 mm (4") diameter or larger if
highly viscous material is being pumped. The suction hose must be non-
collapsible, reinforced type as the T20 is capable of pulling a high vacuum.
Discharge piping should be at least 102 mm (4"); larger diameter can be
used to reduce friction losses. It is critical that all fittings and connections
are airtight or a reduction or loss of pump suction capability will result.
Installation
Months of careful planning, study, and selection efforts can result in
unsatisfactory pump performance if installation details are left to chance.
Premature failure and long term dissatisfaction can be avoided if
reasonable care is exercised throughout the installation process.
Location
Noise, safety, and other logistical factors usually dictate that “utility”
equipment be situated away from the production floor. Multiple installations
with conflicting requirements can result in congestion of utility areas, leaving
few choices for siting of additional pumps.
Within the framework of these and other existing conditions, every pump
should be located in such a way that four key factors are balanced against
each other to maximum advantage.
• Access: First of all, the location should be accessible. If it’s easy to reach
the pump, maintenance personnel will have an easier time carrying out
routine inspections and adjustments. Should major repairs become
necessary, ease of access can play a key role in speeding the repair
process and reducing total downtime.
• Air Supply: Every pump location should have an air line large enough to
supply the volume of air necessary to achieve the desired pumping rate
(see pump performance chart). Use air pressure up to a maximum of
125 psig depending upon pumping requirements.
For best results, the pumps should use an air filter, regulator, and
lubricator system. The use of an air filter before the pump will ensure that
the majority of any pipeline contaminants will be eliminated. The use of a
lubricant, suitable for the application, helps perform a number of functions.
Lubricants reduce friction to minimize required shifting forces and reduce
wear. Lubricants provide a protective coating against some forms of
corrosion and contaminants. Wilden suggests an oil with arctic
characteristics (ISO 15-5Wt.) This oil is chemically compatible with
the center block Glyd™ rings and has a low pour point to guard
against problems associated with low temperatures. The amount of
lubrication required is directly related to the amount of oil introduced from
the factory air system. We therefore suggest that the lowest setting on the
lubricator be utilized and then increased as necessary.
Pump discharge rate can be controlled by limiting the volume and/or
pressure of the air supply to the pump. The use of a needle valve installed
at the air inlet to the pump is suggested for this purpose. Pump discharge
rate can also be controlled by installing a valve in the discharge line of the
pump when the need to control the pump from a remote location exists.
When the pump discharge pressure equals or exceeds the air supply
pressure, the pump will stop; no bypass or pressure relief valve is needed,
and pump damage will not occur. When operation is controlled by a
solenoid valve in the air line, a three-way valve should be used. Pumping
volume can be set by counting the number of strokes per minute. A muffler
installed on the the pump’s air exhaust will give quiet exhaust. Sound levels
are reduced below OSHA specifications using a Wilden muffler
• Elevation Selecting a site that is well within the pump’s suction lift
capability will assure that loss-of-prime troubles will be eliminated. In
addition, pump efficiency can be adversely affected if proper attention is
not given to elevation (see pump performance chart).
• Piping: Final determination of the pump site should not be made until the
piping problems of each possible location have been evaluated. The impact
of current and future installations should be considered ahead of time to make
sure that inadvertent restrictions are not created for any remaining sites.
The best choice possible will be a site involving the shortest and the
straightest hook-up of suction and discharge piping. Unnecessary elbows,
bends, and fittings should be avoided. Pipe sizes should be selected so as
to keep friction losses within practical limits. All piping should be supported
independently of the pump. In addition, it should line up without placing
stress on the pump fittings.
Expansion joints can be installed to aid in absorbing the forces created by
the natural reciprocating action of the pump. If the pump is to be bolted
down to a solid foundation, a mounting pad placed between the pump and
foundation will assist in minimizing pump vibration. Flexible connections
between the pump and rigid piping will also assist in minimizing pump
vibration. If quick-closing valves are installed at any point in the discharge
system, or if pulsation within a system becomes a problem, a surge
suppressor should be installed to protect the pump, piping and gauges
from surges and water hammer.
When pumps are installed in applications involving flooded suction or
suction head pressures, a gate valve should be installed in the suction line
to permit closing of the line for pump service.
The T20 can be used in submersible applications only when both wetted and
non-wetted portions are compatible with the material being pumped. If the
pump is to be used in a submersible application, a hose should be attached
to the pump’s air exhaust and the exhaust air piped above the liquid level.
If the pump is to be used in a self-priming application, be sure that all
connections are airtight and that the suction lift is within the pump’s ability.
Note: Materials of construction and elastomer material have an effect on
suction lift parameters. See pump performance data.
Pumps in service with a positive suction head are most efficient when inlet
pressure is limited to 0.5–0.7 bar (7–10 psig). Premature diaphragm
failure may occur if positive suction is 0.8 bar (11 psig) and higher.
THE MODEL T20 WILL PASS 35 mm (1-3/8") SOLIDS. WHENEVER THE
POSSIBILITY EXISTS THAT LARGER SOLID OBJECTS MAY BE SUCKED INTO
THE PUMP, A STRAINER SHOULD BE USED ON THE SUCTION LINE.
CAUTION: DO NOT EXCEED 8.6 BAR (125 PSIG) AIR SUPPLY
PRESSURE.
BLOW OUT AIR LINE FOR 10 TO 20 SECONDS BEFORE
ATTACHING TO PUMP TO MAKE SURE ALL PIPE LINE DEBRIS IS
CLEAR. ALWAYS USE AN IN-LINE FILTER.
PUMPS SHOULD BE THOROUGHLY FLUSHED WITH WATER
BEFORE INSTALLING INTO PROCESS LINES. FDA AND USDA
APPROVED PUMPS SHOULD BE CLEANED AND/OR SANITIZED
BEFORE BEING USED ON EDIBLE PRODUCTS.
Section 6

WIL-10280-E-04 Wilden®
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Suggested Installation, Operation, Maintenance and Troubleshooting
NOTE: In the event of a power failure, the shutoff valve should
be closed, if the restarting of the pump is not desirable once
power is regained.
Air-Operated Pumps: To stop the pump from operating in an
emergency situation, simply close the “shut-off” valve (user supplied)
installed in the air supply line. A properly functioning valve will stop the
air supply to the pump, therefore stopping output. This shut- off valve
should be located far enough away from the pumping equipment such
that it can be reached safely in an emergency situation.
Operation
Pump discharge rate can be controlled by limiting the volume and/or
pressure of the air supply to the pump (preferred method). A regulator
is used to regulate air pressure. A needle valve is used to regulate air
volume. Pump discharge rate can also be controlled by throttling the
pump discharge by partially closing a valve in the discharge line of the
pump. This action increases friction loss which reduces flow rate. This
is useful when the need exists to control the pump from a remote
location. When the pump discharge pressure equals or exceeds the air
supply pressure, the pump will stop; no bypass or pressure relief valve
is needed, and pump damage will not occur. The pump has reached a
“deadhead” situation and can be restarted by reducing the fluid
discharge pressure or increasing the air inlet pressure. The Wilden T15
pump runs solely on compressed air and does not generate heat,
therefore your process fluid temperature will not be affected.
Maintenance and Inspections
Since each application is unique, maintenance schedules may be
different for every pump. Frequency of use, line pressure, viscosity and
abrasiveness of process fluid all affect the parts life of a Wilden pump.
Periodic inspections have been found to offer the best means for
preventing unscheduled pump downtime. Personnel familiar with the
pump’s construction and service should be informed of any
abnormalities that are detected during operation.
Records
When service is required, a record should be made of all necessary
repairs and replacements. Over a period of time, such records can
become a valuable tool for predicting and preventing future
maintenance problems and unscheduled downtime. In addition,
accurate records make it possible to identify pumps that are poorly
suited to their applications.

WIL-10280-E-04 Wilden®
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Suggested Installation, Operation, Maintenance and Troubleshooting
Troubleshooting
Pump will not run or runs slowly.
1. Check air inlet screen and air filter for debris.
2. Check for sticking air valve, flush air valve in solvent.
3. Check for worn out air valve. If piston face in air valve is
shiny instead of dull, air valve is probably worn beyond
working tolerances and must be replaced.
4. Check center block Glyd™ rings. If worn excessively,
they will not seal and air will simply flow through pump
and out air exhaust. Use only Wilden Glyd™ rings as
they are of special construction and ISO 15-5 wt oil with
arctic characteristics.
5. Check for rotating piston in air valve.
6. Check type of lubricant being used. A higher viscosity oil
than suggested may cause the piston to stick or run
erratically. Wilden suggests the use of a hydraulic oil with
arctic characteristics (ISO 15-5 wt).
Pump runs, but little or no product flows.
1. Check for pump cavitation; slow pump speed down to
match thickness of material being pumped.
2. Check for sticking ball checks. If material being
pumped is not compatible with pump elastomers,
swelling may occur. Replace ball checks and o-rings
with proper elastomers.
3. Check to make sure all suction connections are air tight,
especially clamp bands around intake balls.
Pump air valve freezes.
1. Check for excessive moisture in compressed air.
Either install dryer or hot air generator for compressed air.
Air bubbles in pump discharge.
1. Check for ruptured diaphragm.
2. Check tightness of clamp bands, especially at
intake manifold.
Product comes out air exhaust.
1. Check for diaphragm rupture.
2. Check tightness of piston plates to shaft.
Pump rattles.
1. See E9 Troubleshooting Guide.
2. Create false discharge head or suction lift.

WIL-10280-E-04 Wilden®
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Disassembly / Reassembly
Pump Disassembly
CAUTION : Before any maintenance or repair is attempted, the compressed air
line to the pump should be disconnected and all air pressure allowed to bleed
from pump. Disconnect all intake, discharge and air lines.
The T20 has a 102 mm (4") inlet and 102 mm (4") outlet and is designed for
flows up to 300 gpm. Its air distribution system is based upon design
simplicity and proven efficiency. The model T20 is available in cast iron.
NOTE: Before starting disassembly, mark a line from each liquid chamber to
its corresponding air chamber, as well as a line from the liquid chamber to its
corresponding discharge elbow and ball pot. These lines will assist in proper
alignment during reassembly .
Section 7

WIL-10280-E-04 Wilden®
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Disassembly / Reassembly
Step 1 Figure 1A Figure 1B
Start disassembly by removing the wing nuts from the ball pots. This allows the ball pot cover to be removed, exposing the discharge or inlet
ball valves and ball pot lid o-rings for inspection. (See Figures 1A, 1B.)
Step 2 Figure 2A Figure 2B
Remove clamp bands around the bottom of discharge ball pots. (See Figure 2A). It is now possible, with assistance, to remove the discharge
manifold assembly from the main body of the ump. (See Figure 2B.) This allows for inspection of the valve seats.
Step 3 Figure 3A Figure 3B
Disconnect clamp bands from around the bottom of the inlet ball pots. (See Figure 3A.) It is now possible, with assistance, to remove the main
body of the pump. (See Figure 3B). The pump is now in three sections: 1. Inlet housing 2. Center section housing. 3. Discharge housing

WIL-10280-E-04 Wilden®
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Disassembly / Reassembly
Disassembly & Reassembly of Inlet Housing
Disassembly
Loosen clamp band around inlet elbow. (See Figure 1A.)
Remove the clamp band while supporting the elbow.
This step will allow for inspection of the manifold gasket
between the elbows and inlet-tee. (See Figure 1B.)
Repeat this step for removal of opposite elbow.
Figure 1A Figure 1B
Assembly
Figure 2A
To reassemble, set the tee-section on end. Stretch the gasket lip
around the sealing surface of the tee-section. (See Figure 2A.) Align
the inlet elbow and replace the clamp band. To reassemble the
opposite elbow, balance the assembly on the attached elbow as
shown in Figure 2B. This will allow you to look down the length of
the manifold giving you the proper perspective to align the elbow not
yet attached. Align the second inlet elbow and replace the clamp
band.
Figure 2B
NOTE: To insure that the elbows ar on the same level
plane, rest the manifold on its feet and place a straight
edge diagonally across the full length of the manifold
resting the straight edge on the sealing surface of the
elbows. When level tighten clamp bands.

WIL-10280-E-04 Wilden®
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Disassembly / Reassembly
Disassembly & Reassembly of Center Section Housing
Disassembly
Step 1 Figure 1A
Loosen clamp band around discharge elbow. Remove the clamp band while supporting the elbow. This step will allow for inspection
of the manifold gasket between elbows and water chamber. (See Figure 1A.) Repeat this step for removal of opposite elbow.
Step 2 Figure 2A Figure 2B
Roll the center housing slightly to achieve better access to the clamp band bolts. (See Figure 2A.) Remove the clamp bands connecting
the ball pots to the air chamber. This procedure allows inspection of the manifold gasket between the ball pot and water chamber, as
well as inspection of the ball seat found on the bottom side of the ball pot. (See Figure 2B.)
NOTE: You may want to place blocks on each side of the center section. This will prevent the center section from rolling as the
ball pots are being removed
Step 3
After removing the ball pots set the center section on
end. Loosen and remove the clamp. (See Figure 3A.)
This allows for removal of the water chamber.
(See Figure 3B.)
With the center section still upright loosen and remove
the opposite clamp band. The center section can now
be lifted off of the water chamber, exposing both
diaphragms for inspection
Figure 3A Figure 3B

WIL-10280-E-04 Wilden®
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Disassembly / Reassembly
Disassembly & Reassembly of Center Section Housing
Step 4 Figure 4A
Place the center section as shown in Figure 4A. Place a wrench over the nut at the center of each outer piston, and loosen the outer
piston plate.
Step 5 Figure 5A Figure 5B
Again, place the center section upright so that the diaphragm in the full stroke position is exposed. Using a pry bar, turn the edge of
the diaphragm up. (See Figure 5A.) It is now possible to remove the entire diaphragm assembly by unscrewing the outer piston and
lifting the assembly off the shaft. (Figure 5B.)
Step 6
Gently turn the center section over onto the exposed end of the shaft. Gently push down on the center section which will force the shaft
through the center block. It will then be possible to grip the edges of the diaphragm and pull the remainder of the shaft through the
center block. Unscrew the outer piston and lift the assembly off the shaft. If needed, a vise with wood blocks is the suggested method of
securing shaft while removing the second outer piston. It is important not to score or mark the chrome-plated shaft.
Step 7
To remove the air chamber from the center block simply remove the four flat head screws. This will expose the center block for
inspection. Disassembly of the center block and shaft/piston units are shown below.

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Disassembly / Reassembly
Reassembly of Center Section Housing
Step 1
Prior to reassembly, remove Glyd™ rings from center block bushing and flush the center block, removing grit and contaminants.
Install new Glyd™ rings in center block. Reassemble air valve, center block and air chambers per the torque specifications*.
Step 2 Figure 2A
Pre-assemble the inner piston, diaphragm and outer piston per
the torque specifications*. Attach the pre- assembled diaphragm
configuration to either end of the shaft. Lubricate the bushing
with a 5W non- synthetic, non-detergent oil so that the shaft will
pass through the Glyd™ rings. Insert the shaft firmly into the
bushing. Turn the center section over and push the diaphragm
from full stroke position to exhaust position. This will expose the
shaft so that the other pre-assembled diaphragm configuration
can be positioned. (See Figure 2A.)
Step 3 Figure 2B
Attach the other pre-assembled diaphragm configuration to the
other end of the shaft. After installation of the diaphragm, tighten
the outer pistons by laying the assembly horizontally and tightening
both outer pistons simultaneously per torque specification*.
(See Figure 2A.).
*Refer to Section 8 for required torque specifications

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Disassembly / Reassembly
Step 4 Figure 4A
Return the pump to an upright position. (See Figure 4A.)
Replace gaskets on both sealing surfaces of the water chamber.
Realign one discharge elbow and ball pot. Replace the clamp
bands and tighten per the torque specification*.
Step 5 Figure 5B
Flip the assembly over and stand the unit upright using a block of
wood to support the assembly. (See Figure 5A.) Replace the
gaskets. Realign the discharge elbow and ball pot.
*Refer to Section 8 for required torque specifications

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Disassembly / Reassembly
Disassembly & Reassembly of Discharge Housing
DISASSEMBLY
Step 1 Figure 1A Figure 1B
Loosen clamp bands between ball pots and discharge tee. Remove the bands while supporting the tee-section. This will allow for
inspection of the seals between the ball pots and discharge tee-section (see Figure 1A) as well as inspection of the ball seat found
on the bottom side of the ball pot. (See Figure 1B.)
REASSEMBLY
Step 1
To reassemble the discharge housing, set the tee-section on end. Stretch the gasket lip around
the sealing surface of the tee-section. (See Figure 1C.) Align the ball pot and replace the clamp
band (hand tighten only). To reassemble the opposite ball pot, balance the discharge tee on the
attached ball pot as shown in Figure 1D. Align the ball pot and attach the clamp band. (Hand
tighten only.)
NOTE: To insure that the ball pots are on the
same level plane, rest the manifold horizontally
and place a straight edge diagonally across the
full length of the manifold resting the straight
edge on the sealing surface of the ball pots.
When level tighten clamp bands per the
torque specification*.
Figure 1C Figure 1D