Wilden H800 Troubleshooting guide

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www.wildenpump.com
H800
Advanced™Series
Metal Pump
EOM
Engineering
Operation &
Maintenance
W I L-111 5 0 - E -10
REPLACES W I L-1115 0 - E - 0 9

TABLE OF CONTENTS
SECTION 1 CAUTIONS—READ FIRST! ..............................................1
SECTION 2 WILDEN PUMP DESIGNATION SYSTEM .................................2
SECTION 3 HOW IT WORKS—PUMP & AIR DISTRIBUTION SYSTEM ................3
SECTION 4 DIMENSIONAL DRAWINGS .............................................4
SECTION 5 PERFORMANCE ........................................................5
SECTION 6 SUGGESTED INSTALLATION, OPERATION & TROUBLESHOOTING........6
SECTION 7 ASSEMBLY / DISASSEMBLY ............................................9
SECTION 8 EXPLODED VIEW & PARTS LISTING
H800 Metal - Ductile Iron .............................................18
H800 Metal - Stainless Steel ...........................................19
Center Section ......................................................20
SECTION 9 ELASTOMER OPTIONS.................................................22

1WILDEN PUMP & ENGINEERING, LLC
WIL-1115 0 - E-10
TEMPERATURE LIMITS:
Neoprene –17.7°C to 93.3°C 0°F to 200°F
Buna-N –12.2°C to 82.2°C 10°F to 180°F
Nordel®–51.1°C to 137.8°C –60°F to 280°F
Viton®–40°C to 176.7°C –40°F to 350°F
Saniflex™ –28.9°C to 104.4°C –20°F to 220°F
Wil-Flex™ -40ºC to 107.2ºC –40ºF to 225ºF
Polytetrafluoroethylene (PTFE)
4.4°C to 104.4°C 40°F to 220°F
Polyurethane –12.2°C to 65.6°C 10°F to 150°F
NOTE: Not all materials are available for all
models. Refer to Section 2 for material options
for your pump.
CAUTION: When choosing pump materials, be
sure to check the temperature limits for all wetted
components. Example: Viton®has a maximum
limit of 177°C (350°F) but polypropylene has a
maximum limit of only 79°C (175°F).
CAUTION: Maximum temperature limits are
based upon mechanical stress only. Certain
chemicals will significantly reduce maximum
safe operating temperatures. Consult Chemical
Resistance Guide for chemical compatibility and
temperature limits.
WARNING: Prevent static sparking — If static
sparking occurs, fire or explosion could result.
Pump, valve and containers must be grounded
to a proper grounding point when handling
flammable fluids and whenever discharge of
static electricity is a hazard.
CAUTION: Do not exceed 5.9 bar (85 psig) air
supply pressure.
CAUTION: All piping, valves, gauges and other
components installed on the liquid discharge must
have a minimum pressure rating of 20.7 bar (300 psig).
CAUTION: The discharge pressure generated by
this pump is 3X the inlet pressure supplied.
CAUTION: The process fluid and cleaning fluids
must be chemically compatible with all wetted
pump components. Consult Chemical Resistance
Guide.
CAUTION: Pumps should be thoroughly flushed
before installing into process lines. FDA- and
USDA- approved pumps should be cleaned and/
or sanitized before being used.
CAUTION: Always wear safety glasses when
operating pump. If diaphragm rupture occurs,
material being pumped may be forced out air
exhaust.
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. Drain the pump
by turning it upside down and allowing any fluid
to flow into a suitable container.
CAUTION: Blow out air line for 10 to 20 seconds
before attaching to pump to make sure all pipeline
debris is clear. Use an in-line air filter. A 5μ (micron)
air filter is recommended.
NOTE: Before starting disassembly, mark a line
from each liquid chamber to its corresponding air
chamber. This line will assist in proper alignment
during reassembly.
CAUTION: Wilden H800 High Pressure pumps
cannot be used in submersible applications.
CAUTION: Tighten all hardware prior to installation.
Section 1
CAUTIONS—READ FIRST!

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WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
Section 2
WILDEN PUMP DESIGNATION SYSTEM
H800 METAL
51 mm (2") Pump
Maximum Flow Rate:
360 lpm (95 gpm)
LEGEND
H800 / XXXXX / XXX /XX / X XX /XXXX
O-RINGS
MODEL VALVE SEAT
VALVE BALLS
DIAPHRAGMS
AIR VALVE
CENTER BLOCK
AIR CHAMBERS
WETTED PARTS & OUTER PISTON
SPECIALTY
CODE
(if applicable)
MATERIAL CODES
MODEL
H800 = 51 mm (2") HIGH
PRESSURE
WETTED PARTS
& OUTER PISTON
SS = STAINLESS STEEL/
STAINLESS STEEL
WW = DUCTILE IRON/
DUCTILE IRON
AIR CHAMBERS
S = STAINLESS STEEL
W = DUCTILE IRON
CENTER BLOCK
A = ALUMINUM
AIR VALVE
A = ALUMINUM
DIAPHRAGMS
FWL = FULL-STROKE
SANITARY
WIL-FLEX ™ IPD1
FWS = SANITARY
WIL-FLEX ™ 1
TWS = FULL-STROKE PTFE
W/WIL-FLEX™
BACKUP
VALVE BALL
TF = PTFE (WHITE)
WF = WIL-FLEX™
[SANTOPRENE®
(ORANGE DOT)]
VALVE SEAT
S = STAINLESS STEEL
M = MILD STEEL
VALVE SEAT O-RING
TF = PTFE (WHITE)
WF = WIL-FLEX™
[SANTOPRENE®
(ORANGE DOT)]
NOTE: MOST ELASTOMERIC MATERIALS USE COLORED DOTS FOR IDENTIFICATION.
NOTE: Not all models are available with all material options.
SPECIALTY CODES
0504 DIN flange
Notes: 1 Meets Requirements of FDA CFR21.177

3WILDEN PUMP & ENGINEERING, LLC
WI L-1115 0 - E-10
The Wilden diaphragm pump is an air-operated, positive displacement, self-priming pump. These drawings show flow pattern
through the pump upon its initial stroke. It is assumed the pump has no fluid in it prior to its initial stroke.
FIGURE 1 When air pressure is supplied
to the pump, the air valve directs pressure
to the back side of diaphragm A. The
compressed air moves the diaphragm
away from the center section 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. The movement of
diaphragm B towards the center section
of the pump creates a vacuum within
chamber B. Atmospheric pressure forces
fluid into the inlet manifold forcing the
inlet valve ball off of its seat. Liquid is free
to move past the inlet valve ball and fill
the liquid chamber (see shaded area).
FIGURE 2 Once the shaft has reached the
end of its stroke, the air valve redirects
pressurized air to the back side of
diaphragm B.
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
condition of the application.
The H800 uses an integral power amplifier piston together with two diaphragms to yield a pressure ratio of 3:1 (e.g. 85 psig air
inlet will develop pump discharge pressures up to 250 psig). Air is simultaneously directed behind the amplifier piston as well as
one of the diaphragms via specialized air manifold porting. The sum of the two surface areas is three times that of the diaphragm.
Therefore, the discharge is amplified by a 3:1 pressure output ratio.
Section 3
HOW IT WORKS—PUMP
HOW IT WORKS—THE POWER PRINCIPLE

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WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
Section 4
DIMENSIONAL DRAWINGS
H800 Metal DIMENSIONS
ITEM Metric (mm) Standard (inch)
A 490 19.3
B 89 3.5
C 677 26.7
D 760 29.9
E 378 14.9
F 120 4.7
G 307 12.1
H 498 19.6
J 394 15.5
K 318 12.5
L 325 12.8
M 379 14.9
N 14 0.6
DIN FLANGE
P 125 DIA. 4.9 DIA.
R 165 DIA. 6.5 DIA.
S 18 DIA. 0.7 DIA.
ANSI FLANGE
P 125 DIA. 5.0 DIA.
R 165 DIA. 6.5 DIA.
S 19 DIA. 0.8 DIA.
REV B

5WILDEN PUMP & ENGINEERING, LLC
WI L-1115 0 - E-10
A. P400 Aluminum performance
Curves
Flow rates indicated on chart were determined by pumping water.
For optimum life and performance, pumps should be specified so that daily operation
parameters will fall in the center of the pump's performance curve.
H800 METAL
Section 5
PERFORMANCE (TPE/FULL STROKE PTFE)
Height………………… . ……759 mm (29.9")
Width ...................................490 mm (19.3")
Depth ...................................546 mm (21.5")
Est. Ship Weight...... Stainless Steel 128 kg (283 lb)
Ductile Iron 128 kg (283 lb)
Air Inlet ....................................19 mm (3/4")
Inlet ........................................... 51 mm (2")
Outlet ........................................ 51 mm (2")
Suction Lift ...................... 3.7 m Dry (12.0')
9.0 m Wet (29.5')
Displacement Per Stroke...1.67 L (0.44 gal)
Max. Flow Rate .............. 360 lpm (95 gpm)
Max. Size Solids.................. 12.7 mm (1/2")
1Displacement per stroke was calculated at
4.8 bar (70 psig) air inlet pressure against a
5.1 bar (75 psig) head pressure.
Example: To pump 76 lpm (20 gpm)
against a discharge pressure head of 8.6
bar (125 psig) requires 2.9 bar (42 psig)
and 65 Nm3/h (38 scfm) air consumption.
Caution: Do not exceed 5.9 bar (85 psig) air
supply pressure.
H800 High Pressure Suction Lift Capability
H800 METAL HIGH PRESSURE
SUCTION-LIFT CAPABILITIES
Suction lift curves are calibrated for
pumps operating at 305 m (1,000')
above sea level. This chart is meant
to be a guide only. There are many
variables that can affect your pump’s
operating characteristics. The number of
intake and discharge elbows, viscosity
of pumping fluid, elevation (atmospheric
pressure) and pipe friction loss all affect
the amount of suction lift your pump will
attain.
SUCTION-LIFT CURVE

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WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
Section 6
SUGGESTED INSTALLATION
Wilden pumps are designed to meet the performance
requirements of even the most demanding pumping
applications. They have been designed and manufactured
to the highest standards and are available in a variety of
liquid path materials to meet your chemical resistance
needs. Refer to the performance section of this manual for
an in-depth analysis of the performance characteristics of
your pump. Wilden offers the widest variety of elastomer
options in the industry to satisfy temperature, chemical
compatibility, abrasion resistance and flex concerns.
The suction pipe size should be at least the equivalent or
larger than the diameter size of the suction inlet on your
Wilden pump. The suction hose must be non-collapsible,
reinforced type as these pumps are capable of pulling a high
vacuum. Discharge piping should also be the equivalent
or larger than the diameter of the pump discharge, which
will help 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 where equipment will be situated on the production
floor. Multiple installations with conflicting requirements
can result in congestion of utility areas, leaving few choices
for additional pumps.
Within the framework of these and other existing conditions,
every pump should be located in such a way that six 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. Use air pressure up to
a maximum of 5.9 bar (85 psig) depending on pumping
requirements.
For best results, the pumps should use a 5μ (micron) air
filter, needle valve and regulator. The use of an air filter
before the pump will ensure that the majority of any pipeline
contaminants will be eliminated.
SOLENOID OPERATION: When operation is controlled by a
solenoid valve in the air line, three-way valves should be
used.This valve allows trapped air between the valve and the
pump to bleed off, after which improves pump performance.
Pumping volume can be estimated by counting the number
of strokes per minute and then multiplying the figure by the
displacement per stroke.
MUFFLER: Sound levels are reduced below OSHA
specifications using the standard Wilden muffler. Other
mufflers can be used to further reduce sound levels, but
they usually reduce pump performance.
ELEVATION: Selecting a site that is well within the pump’s
dynamic lift capability will assure that loss-of-prime issues will
be eliminated. In addition, pump efficiency can be adversely
affected if proper attention is not given to site location.
PIPING: Final determination of the pump site should not be
made until the piping challenges 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 straightest hook-up of suction and discharge
piping. Unnecessary elbows, bends and fittings should
be avoided. Pipe sizes should be selected to keep friction
losses within practical limits. All piping should be supported
independently of the pump. In addition, the piping should
be aligned to avoid placing stress on the pump fittings.
Flexible hose 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 location, a mounting
pad placed between the pump and the 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 (SD Equalizer®)
should be installed to protect the pump, piping and gauges
from surges and water hammer.
If the pump is to be used in a self-priming application, make
sure that all connections are airtight and that the suction lift is
within the model’s ability. Note: Materials of construction and
elastomer material have an effect on suction lift parameters.
Please refer to the performance section for specifics.
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.
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 0.7 bar (10 psig) and higher.
ALL WILDEN PUMPS ARE CAPABLE OF PASSING SOLIDS.
A STRAINER SHOULD BE USED ON THE PUMP INTAKE TO
ENSURE THAT THE PUMP'S RATED SOLIDS CAPACITY IS
NOT EXCEEDED.
CAUTION: DO NOT EXCEED 5.9 BAR (85 PSIG) AIR SUPPLY
PRESSURE.

7WILDEN PUMP & ENGINEERING, LLC
WI L-1115 0 - E-10
SUGGESTED INSTALLATION
NOTE: In the event of a power failure, the shut-off
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.

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SUGGESTED OPERATION & MAINTENANCE
OPERATION: Pump discharge rate can be controlled by
limiting the volume and/or pressure of the air supply
to the pump. An air regulator is used to regulate air
pressure. A needle valve is used to regulate 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. (See
Section 5.) 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 H800 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.
TROUBLESHOOTING
Pump will not run or runs slowly.
1. With the use of the flow curve located in the
performance section of this EOM, verify air pressure
and volume required for your application. If inlet
air pressure is too low, the H800 pump will not
operate.
2. Check air inlet filter for debris (see SUGGESTED
INSTALLATION).
3. Disassemble pump and check for obstructions
in the air passageways or objects which would
obstruct the movement of internal parts.
4. Check for sticking ball check valves. If material being
pumped is not compatible with pump elastomers,
swelling may occur. Replace ball check valves and
seals with proper elastomers. Also, as the check
valve balls wear out, they become smaller and can
become stuck in the seats. In this case, replace balls
and seats.
5. Inspect pressure relief valve for damage. Replace if
necessary with genuine Wilden parts.
6. Inspect the center block seals for damage. Replace if
necessary.
Pump runs but little or no product flows.
1. Check for pump cavitation; slow pump speed
down to allow thick material to flow into liquid
chambers.
2. Verify that vacuum required to lift liquid is not
greater than the vapor pressure of the material
being pumped (cavitation).
3. Check for sticking ball check valves. If material being
pumped is not compatible with pump elastomers,
swelling may occur. Replace ball check valves and
seats with proper elastomers. Also, as the check
valve balls wear out, they become smaller and can
become stuck in the seats. In this case, replace balls
and seats.
4. Check tightness of inlet and discharge connections.
5. Check tightness of all fasteners.
Pump air valve freezes.
1. Check for excessive moisture in compressed
air. Either install a dryer or hot air generator for
compressed air. Alternatively, a coalescing filter
may be used to remove the water from the
compressed air in some applications.
Air bubbles in pump discharge.
1. Check for ruptured diaphragm.
2. Check tightness of outer pistons (refer to Section 7).
3. Check tightness of fasteners and integrity of
O-rings and seals, especially at intake manifold.
4. Ensure pipe connections are airtight.
Product comes out air exhaust.
1. Check for diaphragm rupture.
2. Check tightness of outer pistons to shaft.
3. Check tightness of fasteners that connect the inner
piston to the outer piston.

9WILDEN PUMP & ENGINEERING, LLC
WI L-1115 0 - E-10
Section 7
PUMP DISASSEMBLY
Step 1
Put alignment marks on liquid
chambers and air chambers. Use to
properly align center section with
liquid chamber during reassembly.
Step 2
Using a 3/4" wrench, remove liquid
chamber fasteners adjacent to relief
valves.
Step 3
Using a 9/16" wrench, loosen tubing
nuts located by each pressure relief
valve.
REMOVE
NUT/BOLT
Tools Required
• 1/2" Wrench
• 9/16" Wrench
• 5/8" Wrench
• 3/4" Wrench
• 7/8" Wrench
• 1" Wrench
• 5/64" Hex Head Wrench
• 5/32" Hex Head Wrench
• 1/4" Hex Head Wrench
• 5/16" Hex Head Wrench
• O-ring Pick
• Adjustable Wrench
• Snap-Ring Pliers
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 the pump. Disconnect all intake, discharge and air lines. Drain the pump by
turning it upside down and allowing any fluid to flow into a suitable container.
Be aware of any hazardous effects of contact with your process fluid.
REMOVE
NUT/BOLT

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WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
PUMP DISASSEMBLY
Step 4
Using a 1/2" wrench, loosen pipe
fitting and elbow. This will allow
easy access to the relief valve.
Step 5
Using an adjustable wrench, remove
each pressure relief valve.
Step 6
Using a 5/64" hex head wrench,
remove the four fasteners to
disassemble the pressure relief
valve.
Step 7
Inspect for nicks, gouges, chemical
attack or abrasive wear and
reassemble when complete. Replace
if necessary with genuine Wilden
parts. NOTE: Pressure relief valves
are sold as an assembly only.
Step 8
Using a 1/4" hex head wrench,
remove the fasteners that connect
the air valve and air valve gasket
to the center section and lift air
valve and isolator cover away from
pump.
Step 9
Using a pair of snap ring pliers,
remove the top snap ring from the
air valve body.

11 WILDEN PUMP & ENGINEERING, LLC
WI L-1115 0 - E-10
PUMP DISASSEMBLY
Step 10
Hints & Tips – Using an air nozzle,
alternately pressurize top and bottom
bleeder holes until the top end
cap is forced from air valve body.
Caution: End cap may come out with
considerable force. Position a shop rag
or equivalent over the top end cap to
ensure that the end cap doesn’t harm
the pump technician or anyone else in
the immediate area of the pump.
Step 11
Using a 5/16" hex head wrench,
remove the two air valve manifold
fasteners.
Step 12
Located behind the air valve
manifold are four tubes (two small
and two larger) sealed by O-rings.
Remove all four tubes from pump.
Step 13
Using a 1/2" wrench and socket,
remove discharge manifold
fasteners.
Step 14
After removing discharge manifold,
inspect for abrasion in the ball cage
area.
LARGE AIR TUBES
SMALL AIR TUBES
Step 10
Inspect air piston, air valve body and air valve end cap (including air vale
O-ring) for nicks, gouges, chemical attack or abrasive wear. Replace if
necessary with genuine Wilden parts.
Hints & Tips – Using an air nozzle, alternately pressurize top and bottom bleeder
holes until the top end cap is forced from air valve body. Caution: End cap may
come out with considerable force. Position a shop rag or equivalent over the top
end cap to ensure that the end cap doesn’t harm the pump technician or anyone
else in the immediate area of the pump.

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WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
PUMP DISASSEMBLY
Step 15
Remove valve ball, valve seat
and valve seat O-ring from liquid
chamber and inspect.
Hints & Tips – When reinstalling
the valve seat, position valve seat
square side up.
Step 16
Prior to disconnecting the inlet manifold
from the liquid chambers, secure the
center assembly with the use of a crane or
fork lift with straps. To secure the center
assembly, wrap the straps around the air
cylinder. Using two 1/2" wrenches, remove
the inlet manifold fasteners. Caution: The
center assembly is very heavy and could
injure the pump technician or anyone in
the immediate area if the center assembly
were to fall from the inlet manifold.
Step 17
Hints & Tips - With the center
assembly suspended, remove the
fasteners to connect the liquid
chambers to the air chambers.
Step 18
With the liquid chambers removed
and using extreme caution, lower the
power cylinder and air chambers to
a sturdy flat surface and position on
the flat side of the power cylinder.
Step 19
Rotate power cylinder so that the
front (flat) of the power cylinder is
accessible. Using an air nozzle with
a rubber tip and placing a suitable
object over the pressure relief valve
port, pressurize air tube port. This
will cause the diaphragm assembly
to move to one side for ease of
disassembly.
Step 20
Using a 7/8" open-end wrench
placed on the flat of the diaphragm
shaft, and a 1" wrench placed on
the outer piston lug, remove the
diaphragm assembly by turning
counter clockwise.

13 WILDEN PUMP & ENGINEERING, LLC
WI L-1115 0 - E-10
PUMP DISASSEMBLY
Step 21
Using a 5/16" hex head wrench,
remove the fasteners that connect
the inner piston to the diaphragm
assembly. Inspect diaphragm for
nicks, gouges, chemical attack or
abrasion. Replace if necessary with
genuine Wilden parts.
Step 22
Using a 5/16" hex head wrench,
remove the air chamber fasteners.
Step 23
Using a 5/8" wrench, remove the
fasteners that connect the power
cylinder cover to the power cylinder
body.
Step 24
Using an air nozzle with a rubber
tip, apply air to the relief valve port.
This will force the power cylinder
cover away from the power cylinder
body. Inspect shaft bushing seals
and O-ring on power cylinder cover
for damage.
Step 25
Continue to apply air pressure to
the relief valve port until the power
cylinder piston is moved out of the
power cylinder body.
Step 26
Using one hand and steadying the
power cylinder body with the other,
remove power cylinder piston.
Inspect the slipper seal and guide
rings located on the power piston
for damage.
SLIPPER SEAL
GUIDE RINGS

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WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
Step 27
Inspect the two (2) diaphragm
shafts bushings for wear. Replace if
necessary.
AIR VALVE / CENTER SECTION DISASSEMBLY

15 WILDEN PUMP & ENGINEERING, LLC
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POWER CYLINDER REASSEMBLY
Step 1
After attaching the diaphragm shaft
and bushing to the power cylinder
piston, place power cylinder piston
in vice with soft jaws (do not damage
piston). Next, install new slipper
seal.
Hints &Tips – Using a strip of material
(like an old O-ring), slide the material
back and forth until the slipper seal is
positioned above the center groove.
Step 2
Next, place the power cylinder and
power cylinder piston on top of two
blocks of wood or equivalent.
Step 3
Insert new guide rings in outer
grooves. Very easily, begin to
maneuver the power cylinder piston
into the power cylinder body.
Hints & Tips – A conical (tapered)
piece of cylindrical sheet material or
equivalent can be used to hold the
guide rings in place as the power
cylinder piston slides into the power
cylinder body.
Step 4
Using a rubber mallet, lightly tap
power cylinder piston in a circular
fashion until piston is maneuvered
completely into power cylinder
body. When performing this task,
use caution to not damage the guide
rings or slipper seal.
Step 5
As a last step install power cylinder
cover to power cylinder body and
secure with fasteners provided.

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WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
ASSE M BLY:
Upon performing applicable maintenance to the air
distribution system, the pump can now be reassembled.
Please refer to the disassembly instructions for photos
and parts placement. To reassemble the pump, follow
the disassembly instructions in reverse order. The air
distribution system needs to be assembled first, then
the diaphragms and finally the wetted path. Please find
the applicable torque specifications on this page. The
following tips will assist in the assembly process.
• Lubricate air valve bore, center section shaft and
pilot spool bore with NLGI grade 2 white EP bearing
grease or equivalent.
• Clean the inside of the center section shaft bore to
ensure no damage is done to new seals.
• A small amount of NLGI grade 2 white EP bearing
grease can be applied to the muffler and air valve
gaskets to locate gaskets during assembly.
• Make sure that the exhaust port on the muffler plate
is centered between the two exhaust ports on the
center section.
• Stainless bolts should be lubed to reduce the
possibility of seizing during tightening.
MAXIMUM TORQUE SPECIFICATIONS
Part Description H800 Stainless Steel H800 Ductile Iron
Inner Piston Screws* 58.3 N•m (43 ft-lbs) 58.3 N•m (43 ft-lbs)
Outer Piston 140 (103 ft-lbs) 140 (103 ft-lbs)
Air Valve Bolts 9.5 N•m (in-lbs) 9.5 N•m (in-lbs)
Inlet/Discharge Manifold Bolts 17.6 N•m (13 ft-lbs) 163 N•m (120 ft-lbs)
Center Section Cover Bolts 54.0 N•m (40 ft-lbs) 54.0 N•m (40 ft-lbs)
Air Chamber Screws* 88.1 N•m (65 ft-lbs) 163 N•m (120 ft-lbs)
Liquid Chamber Bolts 58.3 N•m (43 ft-lbs) 163 N•m (120 ft-lbs)
*Use #242 removable Loctite®on fastener threads.
Torque all hardware in an opposing torque sequence.
Liquid chamber bolts may require periodic re-tightening.
If liquid chamber pre-load torque values fall below:
(Stainless steel 25 ft-lbs, Iron 80 ft-lbs) retighten both
liquid chambers to a maximum of: (Stainless steel 43
ft-lbs, Iron 120 ft-lbs). Liquid chamber torque loading
must be even. If any of the liquid chamber bolts require
retightening, it is suggested that all liquid chamber
bolts be retightened to ensure even distribution.
BUSHING SEAL INSTALLATION:
PRE-INSTALLATION
• Once all of the old seals have been removed, the
inside of the bushing should be cleaned to ensure
no debris is left that may cause premature damage
to the new seals.
INSTALLATION
The following tools can be used to aid in the installation
of the new seals:
Needle Nose Pliers
Phillips Screwdriver
Electrical Tape
• Wrap electrical tape around each leg of the needle nose
pliers (heat shrink tubing may also be used). This is done
to prevent damaging the inside surface of the new seal.
• With a new seal in hand, place the two legs of the needle
nose pliers inside the seal ring. (See Figure A.)
• Open the pliers as wide as the seal diameter will allow,
then with two fingers pull down on the top portion of
the seal to form kidney bean shape. (See Figure B.)
• Lightly clamp the pliers together to hold the seal into
the kidney shape. Be sure to pull the seal into as tight
of a kidney shape as possible, this will allow the seal to
travel down the bushing bore easier.
• With the seal clamped in the pliers, insert the seal into
the bushing bore and position the bottom of the seal
into the bushing groove. Once the bottom of the seal is
seated in the groove, release the clamp pressure on the
pliers. This will allow the seal to partially snap back to its
original shape.
• After the pliers are removed, you will notice a slight
bump in the seal shape. Before the seal can be properly
resized, the bump in the seal should be removed as
much as possible. This can be done with either the
Phillips screwdriver or your finger. With either the side
of the screwdriver or your finger, apply light pressure
to the peak of the bump. This pressure will cause the
bump to be almost completely eliminated.
• Lubricate the edge of the shaft with NLGI grade 2
white EP bearing grease.
• Slowly insert the center shaft with a rotating motion.
This will complete the resizing of the seal.
• Perform these steps for the remaining seal.
Figure A
SHAFT SEAL
TAPE
Figure B
SHAFT SEAL
TAPE
NEEDLE NOSE
PLIERS
REASSEMBLY HINTS & TIPS

17 WILDEN PUMP & ENGINEERING, LLC
WI L-1115 0 - E-10
NOTES

18
WILDEN PUMP & ENGINEERING, LLC WI L-1115 0 - E-10
Section 8
EXPLODED VIEW & PARTS LISTING
H800 DUCTILE IRON EXPLODED VIEW
FULL STROKE PTFE
LW0188 REV. A