Wanner International Hydra-Cell G-25 Manual

Models: G-25, H-25
W0452
Installation & Service
GH25-991-UK00B
Wanner International Ltd
8/9 Fleet Business Park
Sandy Lane, Church Cr,
Hants, GU52-8BF
Telephone: [phone]
Fax: [phone]
Email: [e-mail]

2GH25-991-UK00B
G/H-25 Contents
Page
Specifications..........................................................................2
Dimensions .............................................................................4
Installation...............................................................................5
Maintenance..........................................................................11
Service (Fluid End) ...............................................................13
Service (Hydraulic End) ........................................................21
Troubleshooting ................................................................... 25
Max Pressure
Metallic: 1000 psi (70 bar)
Non-Metallic: 250 psi (17 bar)
Capacity @ Max Pressure
rpm gpm I/min
G/H-25-X 1050 20.0 76
G/H-25-E 1150 20.2 77
G/H-25-S 1150 15.6 59
G/H-25-I 1150 11.6 44
Delivery @ Max Pressure
revs/gal revs/liter
G/H-25-X 52 14
G/H-25-E 57 15
G/H-25-S 74 19
G/H-25-I 99 26
Max Inlet Pressure Metallic: 250 psi (17 bar)
Non-Metallic: 50 psi (3.5 bar)
Max Temperature
Metallic: 250°F (121°C) – consult factory for
temperatures above 160°F (71°C)
Non-Metallic: Polypropylene 120°F (49°C)
Kynar 140°F (60°C)
Inlet Port H-25: 1-1/2 inch NPT
G-25: 1-1/2 inch BSPT
Discharge Port H-25: 1 inch NPT
G-25: 1 inch BSPT
Shaft Diameter 1-1/8 inch (28.58 mm)
+
50 x rpm
63,000
gpm x psi
1,460
= electric motor HP*
G/H-25 Specifications
+
50 x rpm
84,428
lpm x bar
511
= electric motor kW*
Calculating Required
Horsepower (kW)*
* rpm equals pump shaft rpm. HP/kW is required application
power. Use caution when sizing motors with variable speed
drives.
Shaft Rotation Bi-directional
Bearings Tapered roller
Oil Capacity 2.5 US quarts (2.4 liters)
Weight
Metallic Heads: 125 lbs (56.8 kg)
Non-Metallic Heads: 90 lbs (40.9 kg)

3GH25-991-UK00B
G/H-25 Specifications
RPM
0
NPSHr (feet of water)
NPSHr (meters of water)
1050
1150
0
H/G-25-X
H/G-25-E
H/G-25-S
H/G-25-I
100 200 300 400 500 600 700 800 900 1000 1100 1200
2
4
6
8
10
12
14
16
18
20
22
24
0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
W0206
RPM
0 12001000800600400200
1050
1150
H/G-25-E
H/G-25-X
H/G-25-S
H/G-25-I
Gallons Per Minute
Liters Per Minute
16.0
20.0
24.0
32.0
36.0
40.0
28.0
44.0
48.0
52.0
56.0
60.0
64.0
68.0
72.0
76.0
80.0
84.0
88.0
4.0
8.0
12.0
0
24.0
0
22.0
20.0
18.0
16.0
14.0
12.0
10.0
8.0
6.0
4.0
2.0
200 PSI (14 bar)
500 PSI (35 bar)
1000 PSI (70 bar)
W0207
RPM
0
Lift (feet of water)
Lift (meters of water)
0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
0
1.0
0.5
1.5
2.0
2.5
200 400 600 800 1000 1200
H/G-25-X
H/G-25-E
H/G-25-S
H/G-25-I
W0205
Performance Net Positive Suction Head –
NPSHr
Dry Lift

4GH25-991-UK00B
G/H-25 Dimensions
Models with Metallic Pumping Head
Models with Non-metallic Pump Head
Brass
Cast Iron
316 Stainless Steel
Nickel Alloy (Hastelloy CW12MW)
Kynar®
Polypropylene
17.01
(432)
13.2
(336)
4.01
(102)
11.58
(294)
1.5
(38) 7.5
(191)
9.98
(253)
0.25
(6.4)
Slot Width
0.42
(11) Slot Width
4.5
(114)
2.25
(57)
10.0
(254)
5.63
(143)
Ø1.125
(28.55)
9.44
(240)
Oil
Drain
Outlet
H-25: 1" NPT
G-25: 1" BSPT
Inlet
H-25: 1 1/2" NPT
G-25: 1 1/2" BSPT
3/8" - 18 NPT
(Drain Port)
Oil Fill Cap
0.25
(6.4)
Keyway
2.25
(57)
x
W0450
8.71
(221)
17.8
(452)
14.0
(356)
0.42
(11) Slot Width
4.5
(114)
2.25
(57)
10.0
(254)
5.63
(143)
Ø1.125
(28.55)
Oil Fill Cap
0.25
(6.4)
Keyway
2.25
(57)
x
1.5
(38)
7.5
(191)
9.98
(253)
0.25
(6.4)
Slot Width
Oil
Drain
3/8" - 18 NPT
(Drain Port)
Outlet
H-25: 1" NPT
G-25: 1" BSPT
Inlet
H-25: 1 1/2" NPT
G-25: 1 1/2" BSPT
W0451
4.82
(122)
11.58
(294)
8.71
(221)
9.44
(240)

5GH25-991-UK00B
GH-25 Installation
Safety Precautions
General remarks
These safety / installation instructions contain fundamental
information and precautionary notes and must be kept available
to all associated with the operation of the pump. Please read
them thoroughly prior to installation, electrical connection and
commissioning of the unit. It is imperative that all other operating
instructions relating to the components of individual units are
followed.
These safety / installation instructions do not take local
regulations into account. The operator must ensure that such
regulations are observed by all, including the personnel carrying
out the installation.
Each pump must be labeled by the end user to warn of any
hazards that the system process may produce; e.g. corrosive
chemicals or hot process etc.
All personnel involved in the operation, maintenance, inspection
and installation of the pump must be fully qualified to carry out
the work. The personnel’s responsibilities, competence and
supervision must be clearly defined by the operator. To the extent
that if the personnel in question is not already in possession of
the requisite know how, appropriate training and instruction must
be provided. In addition, the operator is responsible for ensuring
that the contents of the operating instructions are fully understood
by all the responsible personnel.
When installing a Hydra-Cell pump in conjunction with a motor
or motor and frequency controller the relevant manuals must
be referred to for electromagnetic compatibility. The installation
should conform to EN 61800 and EN 60204.
All safety instructions in this manual and all relevant local health
and safety regulations must be followed.
Attention must be paid to the weight of the pump before
attempting to lift either manually or selecting appropriate lifting
equipment.

6GH25-991-UK00B
GH-25 Installation
Note: The numbers in parentheses are the reference
numbers on the illustrations in the Parts Manual.
Location
Locate the pump as close to the supply source as possible.
Install it in a lighted clean space where it will be easy to inspect
and maintain. Allow room for checking the oil level, changingthe
oil, and removing the pump head (manifold, valve plate and
related items).
Mounting
The pump shaft can rotate in either direction. To prevent vibration,
mount the pump and motor securely on a level rigid base.
On a belt-drive system, align the sheaves accurately; poor
alignment wastes horsepower and shortens the belt and bearing
life. Make sure the belts are properly tightened, as specified by
the belt manufacturer.
On a direct-drive system, align the shafts accurately. Unless
otherwise specified by the coupling manufacturer, maximum
parallel misalignment should not exceed 0.4 mm (0.015 in.)
and angular misalignment should be held to 1° maximum.
Careful alignment extends life of the coupling, pump, shafts,
and support bearings. Consult coupling manufacturer for exact
alignment tolerances.
Drive couplings, belts and pulleys must be of suitable design,
correctly sized and fitted and rated for the maximum load
required.
On a close-coupled system, coat the motor shaft liberally with
anti-seize.
The pump, motor and related components must be adequately
earthed.
Important Precautions
Adequate Fluid Supply. To avoid cavitation and premature
pump failure, be sure that the pump will have an adequate
fluid supply and that the inlet line will not be obstructed.
See “Inlet Piping”.
Positive Displacement. This is a positive-displacement
pump. To avoid severe system damage if the discharge line
ever becomes blocked, install a relief valve downstream
from the pump. See “Discharge Piping”. A suitable and
calibrated pressure gauge should be installed in the
discharge line close to the pump head.
Safety Guards. Install adequate safety guards over
all pulleys, belts, and couplings. Follow all codes and
regulations regarding installation and operation of the
pumping system.
Shut-Off Valves. Never install shut-off valves between the
pump and discharge pressure regulator, or in the regulator
bypass line.
Freezing Conditions. Protect the pump from freezing. See
also the Maintenance Section.
Working Pump. The pump body will become hot during
operation even if the liquid being pumped is cold.
Consult the Factory for the following situations:
• Extreme temperature applications – above 71°C (160° F)
or below 4.4°C (40° F)
• Pressure feeding of pumps
• Viscous or abrasive fluid applications
• Chemical compatibility problems
• Hot ambient temperatures – above 43°C (110° F)
• Conditions where pump oil may exceed 93°C (200° F)
because of a combination of hot ambient temperatures,
hot fluid temperature, and full horsepower load — an
oil cooler may be required
W0520
Suction
Discharge
Line
Inlet
To Tank
Bypass
Line
Line
Pressure
Gauge
Pressure
Regulator
Vacuum Pressure
Gauge

7GH25-991-UK00B
GH-25 Installation
Inlet Piping (Suction Feed)
CAUTION: When pumping at temperatures above 71°C (160° F),
attention must be paid to the vapour pressure curve of the
liquid. A pressure-feed system may be required.
Install drain cocks at any low points of the suction line, to permit
draining in freezing conditions.
Provide for permanent or temporary installation of a vacuum
gauge to monitor the inlet suction. To maintain maximum flow,
vacuum at the pump inlet should not exceed 180 mm Hg at 21°
C (7 in. Hg at 70° F).
Do not supply more than one pump from the same inlet line.
With PTFE diaphragms, the inlet must be flooded.
Supply Tank
Use a supply tank that is large enough to provide time for any
trapped air in the fluid to escape. The tank size should be at least
twice the maximum pump flow rate.
Isolate the pump and motor stand from the supply tank, and
support them separately.
Install a separate inlet line from the supply tank to each pump.
Install the inlet and bypass lines so they empty into the supply
tank below the lowest water level, on the opposite side of the
baffle from the pump suction line.
If a line strainer is used in the system, install it in the inlet line
to the supply tank.
To reduce aeration and turbulence, install a completely
submerged baffle plate to separate the incoming and outgoing
liquids.
Install a vortex breaker in the supply tank, over the outlet port
to the pump.
Place a cover over the supply tank, to prevent foreign objects
from falling into it.
Hose and Routing
Size the suction line at least one size larger than the pump inlet,
and so that the velocity will not exceed 0.3 to 0.9 m/s (1-3 ft/
sec):
For pipe in mm: Velocity (m/sec) = 21.2 x LPM/Pipe ID2
For pipe in inches: Velocity (ft/sec) = 0.408 x GPM/Pipe ID2
Keep the suction line as short and direct as possible. A maximum
of 1m (3 feet) is recommended.
Use flexible hose and/or expansion joints to absorb vibration,
expansion, or contraction.
If possible, keep the suction line level. Do not have any high
points to collect vapor unless these high points are vented.
To reduce turbulence and resistance, do not use 90° elbows. If
turns are necessary in the suction line, use 45° elbows or arrange
sweeping curves in the flexible inlet hose.
If a block valve is used, be sure it is fully opened so that the flow
to the pump is not restricted. The opening should be at least the
same diameter as the inlet plumbing ID.
Do not use a line strainer or filter in the suction line unless regular
maintenance is assured. If used, it should have a free-flow area
of at least three times the free-flow area of the inlet.
Install piping supports where necessary to relieve strain on the
inlet line and to minimize vibration.

8GH25-991-UK00B
GH-25 Installation
Inlet Piping (Pressure Feed)
Provide for permanent or temporary installation of a vacuum/
pressure gauge to monitor the inlet vacuum or pressure.
Pressure at the pump inlet should not exceed 17 bar (250 psi);
if it could get higher, install an inlet pressure reducing regulator.
Do not supply more than one pump from the same inlet line.
Inlet Calculations
Acceleration Head
Calculating the Acceleration Head
Use the following formula to calculate acceleration head losses.
Subtract this figure from the NPSHa, and compare the result to
the NPSHr of the Hydra-Cell pump.
Ha = (L x V x N x C) ÷ (K x G)
where:
Ha = Acceleration head (ft of liquid)
L= Actual length of suction line (ft) — not equivalent length
V= Velocity of liquid in suction line (ft/sec) [V = GPM x (0.408 ÷
pipe ID2)]
N= RPM of crank shaft
C= Constant determined by type of pump — Use 0.066 for D/
G03, M03, M23, G13, D/G10, D/G04 and H/G25 pumps.
Use 0.04 for D/G35 and D/G15 pumps. Use 0.628 for
F/G20/21/22 pumps.
K= Constant to compensate for compressibility of the fluid — use:
1.4 for de-aerated or hot water; 1.5 for most liquids; 2.5 for
hydrocarbons with high compressibility
G= Gravitational constant (32.2 ft/sec2)
Friction Losses
Calculating Friction Losses in Suction Piping
When following the above recommendations (under “inlet Piping”)
for minimum hose/pipe I.D. and maximum length, frictional losses
in the suction piping are negligible (i.e., Hf = 0) if you are pumping
a water-like fluid.
When pumping more-viscous fluids such as lubricating oils,
sealants, adhesives, syrups, varnishes, etc., frictional losses
in the suction piping may become significant. As Hf increases,
the available NPSH (NPSHa) will decrease, and cavitation will
occur.
In general, frictional losses increase with increasing viscosity,
increasing suction-line length, increasing pump flow rate, and
decreasing suction-line diameter. Changes in suction-line
diameter have the greatest impact on frictional losses: a 25%
increase in suction-line diameter cuts losses by more than
two times, and a 50% increase cuts losses by a factor of five
times.
Consult the factory before pumping viscous fluids.
Minimizing Acceleration Head and Frictional Losses
To minimize the acceleration head and frictional losses:
• Keep inlet lines less than 1 m (3 ft) long
• Use inlet hose at least one size larger than the size of the
inlet port of the pump
• Use soft hose (low-pressure hose, non collapsing) for the
inlet lines
• Minimize fittings (elbows, valves, tees, etc.)
• Use a suction stabilizer on the inlet.

9GH25-991-UK00B
GH-25 Installation
Net Positive Suction Head
NPSHa must be equal to or greater than NPSHr. If not, the
pressure in the pump inlet will be lower than the vapor pressure
of the fluid— and cavitation will occur.
Calculating the NPSHa
Use the following formula to calculate the NPSHa:
NPSHa = Pt + Hz - Hf - Ha - Pvp
where:
Pt = Atmospheric pressure
Hz = Vertical distance from surface liquid to pump center line (if
liquid is below pump center line, the Hz is negative)
Hf = Friction losses in suction piping
Ha = Acceleration head at pump suction
Pvp = Absolute vapor pressure of liquid at pumping
temperature
Notes:
• In good practice, NPSHa should be 3 ft greater than
NPSHr
• All values must be expressed in feet of liquid
Atmospheric Pressure at Various Altitudes
Altitude Pressure Altitude Pressure
(ft) (ft of H2O) (ft) (ft of H2O)
0 33.9 1500 32.1
500 33.3 2000 31.5
1000 32.8 5000 28.2
Discharge Piping
Note: Consult the Factory before manifolding two or more
pumps together.
Hose and Routing
Use shortest, most-direct route for discharge line.
Select pipe or hose with working pressure rating of at least 1.5
times maximum system pressure. EXAMPLE: Select a 1500-psi
W. P.-rated hose for systems to be operated at 1000-psi-gauge
pressure.
Use about 6 ft (1.8 m) of flexible hose between pump and rigid
piping to absorb vibration, expansion or contraction.
Support pump and piping independently. Size discharge line so
that velocity of fluid will not exceed 2-3 m/sec (7-10 ft/sec):
For pipe in mm: Velocity (m/sec) = 21.2 x LPM/Pipe ID2
For pipe in inches: Velocity (ft/sec) = 0.408 x GPM/Pipe ID2
NOTE: Pumps with non-metallic pumping head are limited
to 17 bar (250 psi) maximum working pressure rating.
Pressure Regulation
Install pressure regulator or unloader in discharge line.
Bypass pressure must not exceed pressure limit of pump.
Size regulator so that, when fully open, it will be large enough
to relieve full capacity of pump without over pressurizing the
system.
Locate regulator as close to pump as possible and ahead of
any other valves.
Adjust pressure regulator valve to no more than 10% over
maximum working pressure of system. Do not exceed
manufacturer’s pressure rating for pump or regulator.
Route the bypass line to the supply tank, not to the suction line
(to reduce the chance of turbulence and cavitation within the
pump).
If the pump may be run for a long time with the discharge closed
and fluid bypassing, install a thermal protector in the bypass line
(to prevent severe temperature buildup in the bypassed fluid).
The safety, pressure regulating valve must be checked for correct
operation on a regular basis.
CAUTION: Never install shutoff valves in the bypass line or
between the pump and pressure regulator or relief valve.
Provide for permanent or temporary installation of pressure
gauge to monitor discharge pressure at pump.
For additional system protection install safety relief valve in
discharge line downstream from pressure regulator.

10 GH25-991-UK00B
GH-25 Installation
Before Initial Start-Up
Before you start the pump, be sure that:
• All shut-off valves are open, and pump has adequate supply
of fluid.
• All connections are tight.
• The oil is at the correct level for the model of pump;
D/G10, D/G04, G/H25, D/G15, D/G35– ¼ in. (6mm) above
the cast surface in the upper oil reservoir
F/G20/21/22 - The oil reservoir beneath the reservoir
diaphragm is completely full. NOTE: The reservoir is filled
and sealed at the factory. If you are unsure about the oil
level, remove the cover and slowly lift the diaphragm. Refer
to Service Procedure #6, “Fill and Seal the Oil Reservoir”, in
the Fluid-End Service Section.
D/G03 - The oil level should be 3/4 in. (20 mm) from the top
of the fill port.
• The relief valve on the pump outlet is adjusted so the pump
starts under minimum pressure.
• All pulleys and belts are properly aligned, and belts are
tensioned according to specification.
• All pulleys and belts have adequate safety guards.
• Ensure that the materials of construction of the pump are
compatible with the liquid being pumped.
Initial Start-Up Procedure
1. Turn on power to pump motor.
2. Check inlet pressure or vacuum. To maintain maximum flow,
inlet vacuum must not exceed 180 mm Hg at 21°C (7 in. Hg
at 70° F). Inlet pressure must not exceed 17 bar (250 psi).
3. Listen for any erratic noise and look for unsteady flow.
4. If system has airlock and pump fails to prime:
a. Turn off power.
b. Remove pressure gauge or plug from tee fitting at
pump outlet (refer to illustration drawing at the front of this
section).
Note: Fluid may come out of this port when the plug
is removed. Provide an adequate catch basin for fluid
spillage, if required. Fluid will come out of this port
when the pump is started, so we recommend that you
attach adequate plumbing from this port so fluid will
not be sprayed or lost. Use high-pressure-rated hose
and fittings from this port. Take all safety precautions
to assure safe handling of the fluid being pumped.
c. Jog system on and off until fluid coming from this port is
air-free.
d. Turn off power.
e. Remove plumbing that was temporarily installed, and
reinstall pressure gauge or plug.
5. Adjust discharge pressure regulator to desired operating and
bypass pressures. Do not exceed maximum pressure rating
of pump.
6. After pressure regulator is adjusted, set safety relief valve at
7 bar (100 psi ) higher than desired operating pressure. To
verify this setting, adjust discharge pressure regulator upward
until relief valve opens. Follow recommendations in Note
(step 4b) for handling fluid that will come from relief valve.
7. Reset discharge pressure regulator to desired system
pressure.
8. Provide return line from relief valve to supply tank, similar to
bypass line from pressure regulator.

11 GH25-991-UK00B
G/H-25 Maintenance
NOTE: The numbers in parentheses are the Reference
Numbers on the exploded view illustrations found in this
manual and in the Parts Manual.
Daily
Check the oil level and the condition of the oil. The oil level
should be 1/4 in. (6 mm) above the cast surface in the upper
oil reservoir.
Use the appropriate Hydra-Oil for the application (contact
Wanner Engineering if in doubt).
CAUTION: If you are losing oil but don’t see any external
leakage, or if the oil becomes discolored and contaminated,
one of the diaphragms (22) may be damaged. Refer to the
Fluid-End Service Section. Do not operate the pump with
a damaged diaphragm.
CAUTION: Do not leave contaminated oil in the pump
housing or leave the housing empty. Remove contaminated
oil as soon as discovered, and replace it with clean oil.
Periodically
Change the oil after the first 100 hours of operation, and then
according to the guidelines below. When changing, remove
the drain plug cap (34) at the bottom of the pump so all oil and
accumulated sediment will drain out.
Hours Between Oil Changes @ Various
Process Fluid Temperatures
<90°F <139°F <180°F
Pressure RPM (32°C) (60°C) (82°C)
Metallic Pump Head
<650 psi (45 bar) <800 6,000 4,500 3,000
<1200 4,000 3,000 2,000
<1000 psi (70 bar) <800 4,000 3,000 2,000
<1200 2,000 1,500 1,000
Non-Metallic Pump Head
<250 psi (17 bar) <800 4,000 3,000 —
<1200 2,000 1,500 —
NOTE: Minimum oil viscosity for proper hydraulic end
lubrication is 16-20 cST (80-100 SSU).
NOTE: Use of an oil cooler is recommended when process
fluid and/or hydraulic end oil exceeds 180°F (82°C)
for Metallic Pump Head models or when hydraulic end
oil exceeds 180°F (82°C) for Non-Metallic Pump Head
models.
CAUTION: Do not turn the drive shaft while the oil reservoir
is empty.
Check the inlet pressure or vacuum periodically with a gauge.
If vacuum at the pump inlet exceeds 7 in. Hg (180 mm Hg),
check the inlet piping system for blockages. If the pump inlet
is located above the supply tank, check the fluid supply level
and replenish if too low.
CAUTION: Protect the pump from freezing. Refer also to
the “Shutdown Procedure”.

12 GH25-991-UK00B
Shutdown Procedure During
Freezing Temperatures
Take all safety precautions to assure safe handling of the
fluid being pumped. Provide adequate catch basins for
fluid drainage and use appropriate plumbing from drain
ports, etc. when flushing the pump and system with a
compatible antifreeze.
1. Adjust the discharge pressure regulating valve so the pump
runs under minimum pressure. Stop the pump.
2. Drain supply tank; open any draincocks in system piping and
collect drainage; remove plug (4) from manifold and collect
drainage.
3. Close draincocks in system piping and replace manifold
plug.
4. Fill supply tank with enough antifreeze to fill system piping
and pump.
NOTE: Disconnect the system return line from the supply
tank and connect it to a separate reservoir.
5. Start the pump and allow it to run until the system is filled
with antifreeze. NOTE: If the system has an airlock and
the pump fails to prime, follow step 4 of the Initial Start-
Up Procedure to clear the air.
6. When mostly antifreeze is flowing from the system return line
stop the pump. Connect the system return line back to the
supply tank and circulate the antifreeze for a short period.
7. It is also good practice to change the oil in the hydraulic
end before storage for an extended period. This will remove
any accumulated condensation and sediment from the
oil reservoir. Drain and refill the hydraulic end with the
appropriate Hydra-Oil and operate the pump for a short
period to assure smooth performance.
G/H-25 Maintenance

13 GH25-991-UK00B
G/H-25 Service (Fluid End)
Models with Non-Metallic Pump Head
W0195B
5
6
1
2
4
43
9
10
8
38
11
12
13
14
15
16
39
18
19
20
21
23
22
37
36
3433
24
35
26
6
25
30
42
28 27
32
41
40
29
7

14 GH25-991-UK00B
W0194B
38
11
12
13
14
16
*
*
38
17
Valve Assemblies
with metal spring retainers
‡
*Not included with brass pump heads.
†With brass external-centerbolt models,
use #8; with all other models, use #3.
‡With cast iron pump heads, use #17
and not #10; with all other heads, use
#10 and not #17.
5
6
1
2
4
7
9
10 ‡
17 ‡
83
†
38
*
11
12
13
14
15
16
39
18
19
20
21
23
22
37
36
3433
24
35
26
6
25
30
42
28 27
32
41
40
29
18
Ref
G/H-25 Service (Fluid End)
Models with Metallic Pumping Head
8
10 9
Valve PlateManifold
Brass
Stainless
Steel
Cast
Iron
Valve PlateManifold
Valve PlateManifold
10 9
3
3
9
17
W0208

15 GH25-991-UK00B
G/H-25 Service (Fluid End)
NOTE: The numbers in parentheses refer to the parts
illustrations.
This section explains how to disassemble and inspect all
easily-serviceable parts of the pump. Repair procedures for
the hydraulic end (oil reservoir) of the pump are included in a
later section of the manual.
CAUTION: Do not disassemble the hydraulic end unless
you are a skilled mechanic. For assistance, contact Wanner
Engineering (TEL [phone] or FAX [phone]) or
the distributor in your area.
CAUTION: The four bolts (26) that screw through the back
of the housing into the cylinder casting hold the casting
over the hydraulic end of the pump. Do not remove them
except when repairing the hydraulic end.
1. Remove Manifold (7), and
Valve Plate (18)
a. Remove all bolts (5) and lockwashers (6) around
manifold (7). Do not remove four bolts (26) that are
installed through back of pump housing (30).
b. With 3/8-in (10 -mm) hex Allen wrench, remove
centerbolt (1) and washer (2) in center of manifold.
CAUTION: Do not turn the pump drive shaft while
the manifold and valve plate are off the pump,
except when removing diaphragms or repriming the
hydraulic cells.
c. Remove manifold (7) and support plate (43, used on
non-metallic pump only).
d. Inspect manifold for warping or wear around inlet and
outlet ports. If wear is excessive, replace manifold.
To check for warped manifold, remove O-rings and place
straightedge across it. If warped replace.
e. Remove three socket-head cap screws (39) with 3/16-in.
(5-mm) hex Allen wrench.
f. Inspect valve plate (18) for warping as in step d for
manifold. If warped replace.
NOTE: Plastic valve plates and manifolds should
also be inspected for cracks, and replaced as
necessary.

16 GH25-991-UK00B
W0200A
2. Inspect Valve Assemblies
(parts 11-16, and 38)
NOTE: The three inlet and three outlet valve assemblies
in the pump are identical (but face in opposite
directions).
Inspect each valve assembly as follows:
a. Check spring retainer (16), and replace if worn.
b. Check valve spring (14). If shorter than new spring,
replace. (Don’t stretch old spring.)
c.
Check valve poppet (13). If worn, replace.
NOTE: If pump has plastic spring retainers, there is
a tetra seal O-ring (15) between the retainer (16) and
valve seat (12).
d. Remove valve seat (12). (Seat remover is included in
Wanner Tool Kit.) On cast iron valve plates, be careful
not to break metal ridge around O-ring groove.
Inspect valve seat for wear.
If worn, replace and install
new O-ring (11).
e. Reinstall valve assemblies:
• Clean valve ports and valve shoulders with emery
cloth, and grease with lubricating gel or petroleum
jelly.
• Install O-ring (11) on valve seat (12).
NOTE: Some pumps use plastic dampening
washers (38) between the valve seat (12) and the
manifold (7) or valve plate (18). Refer to the parts
illustrations and the fluid-end exploded views in
the Parts Manual.
• Inlet (3 center valves). Insert retainer (16) into valve
plate (18), then spring (14), valve (13), and valve
seat (12). If pump has plastic retainers, O-ring (15)
goes between retainer and seat.
• Outlet (3 outer valves). Insert valve seat (12), valve
(13), and spring (14), then retainer (16). If pump has
plastic retainers, install the O-ring (15) between
retainer and seat. If pump has metal retainers in outlet
valves, position them so leg does not point toward
center of pump. See illustration following.
G/H-25 Service (Fluid End)

17 GH25-991-UK00B
G/H-25 Service (Fluid End)
3. Inspect and Replace
Diaphragms (22)
a. Lift diaphragm (22) by one edge, and turn pump shaft
until diaphragm pulls up. This will expose machined cross
holes in valve plunger shaft behind diaphragm.
b. Insert Allen wrench through one of holes, to hold
diaphragm up. (The proper size tool is included in the
Wanner Tool Kit.)
c. Remove screw (19), O-ring (20), and follower (21) in
center of diaphragm.
d. Remove diaphragm and inspect carefully.
NOTE: A ruptured diaphragm indicates a pumping
system problem, and replacing only the diaphragm
will not solve the larger problem.
Inspect diaphragm (22) for following:
• Half-moon marks. Usually caused by cavitation of
pump (See Troubleshooting section).
• Concentric circular marks. Usually caused by
cavitation of pump (See Troubleshooting section).
• Small puncture. Usually caused by sharp foreign
object in fluid, or by ice particle.
• Diaphragm pulled away from center screw or from
cylinder sides. Usually caused by fluid being frozen in
pump, or by overpressurization of pump.
• Diaphragm stiff and inflexible. Usually caused by
pumping fluid incompatible with diaphragm material,
or diaphragm operated at temperatures below rated
capability.
• Diaphragm edge chewed away. Usually caused by
overpressurizing system.
f. Inspect plunger (23) for any rough surfaces or edges.
Do not remove plunger from valve plunger (54). Smooth
surfaces and edges as necessary with emery cloth or
fine file.
CAUTION: If a diaphragm has ruptured and foreign
material or water has entered the oil reservoir, do
not operate the pump. Check all diaphragms, then
flush the reservoir completely (as outlined below)
and refill it with fresh oil. Never let the pump stand
with foreign material or water in the reservoir, or with
the reservoir empty.
g. Install new diaphragm (22) or reinstall old diaphragm (if
good) ridge side out.
h. Clean screw (19) including any oil. Apply medium-
strength threadlocker to screw. Reinstall screw, follower
(21), and new O-ring (20). Tighten to 18 in.-lbs (2.0
N-m).
i. Repeat steps a. thru h. for other two diaphragms (22).
Replace diaphragms if indicated.

18 GH25-991-UK00B
4. Flush Contaminant from
Hydraulic End (use if
diaphragm has ruptured)
a. Remove oil drain cap (34) and allow all oil and
contaminants to drain out. Replace oil drain cap.
b. Remove oil cap (28) and fill reservoir with kerosene or
solvent, manually turn pump shaft to circulate kerosene,
and drain.
CAUTION: If you have EPDM diaphragms, or if food
grade oil is in the reservoir, do not use kerosene or
solvents. Instead, flush with the same lubricant used
in the reservoir. Pumps with EPDM diaphragms have
an “E” as the 7th digit of the Model No.
c. Repeat step b.
d. Fill reservoir with fresh oil, manually turn pump shaft to
circulate oil, and drain once again.
e. Refill reservoir. If oil appears milky, there is still
contaminant in reservoir. Repeat flushing procedure until
oil appears clean.
d. Replace oil cap (28).
5A. Prime Hydraulic Cells on
Standard Pumps
a. With pump horizontal, and fluid-end head removed,
remove oil cap (28) and fill reservoir with correct Hydra-
oil for application. Have catch basin for oil leaks from
behind diaphragms when priming. Catch oil and dispose
of properly. Do not reuse.
b. Force air out of oil in hydraulic cell (behind diaphragms)
by turning shaft and pumping piston. (A shaft rotator is
included in the Wanner Tool Kit.) Turn shaft until bubble-
free flow of oil comes from behind all diaphragms. Watch
oil level in reservoir. If oil gets too low during priming,
air will be drawn into pistons (inside hydraulic end) and
cause pump to run rough.
c. Wipe excess oil from cylinder housing (25) and
diaphragms (22).
d. Ensure that oil is one inch (25 mm) from top of fill port.
e. Replace oil cap (28).
G/H-25 Service (Fluid End)
5B. Prime Hydraulic Cells
on Kel-Cell Pumps
NOTE: Providing oil prime to Kel-Cell fitted pumps
requires pressure be applied to the diaphragms. This
can be done manually, with the system head pressure,
or with pressurized air if available. Review all methods
below to determine the procedure most suitable.

19 GH25-991-UK00B
G/H-25 Service (Fluid End)
5B. Prime Hydraulic Cells
on Kel-Cell Pumps (Cont’d)
Method #1 (with system head pressure
less than 2 psi)
a. Install valve plate (18) without outlet valves (leave
seats (12) installed) onto cylinder housing (25). Tighten
two socket-head screws (39).
b. Remove oil cap (28) and fill reservoir with correct Hydra-
oil to top of fill port.
c. With blunt pointer (eraser end of pencil), reach in through
each outlet valve port and push follower-diaphragm
backwards. Note air bubbles coming out at oil fill port.
Now turn shaft about 1/2 turn.
d. Repeat depressing diaphragms and rotating shaft
(approximately 4 to 6 times) until no more air bubbles
escape and oil has dropped about 1 inch (25 mm) from
top of fill port. Hydraulic cells are now primed. Replace
oil cap (28).
e. Install outlet valve assemblies in each outlet valve port.
See parts illustration for correct assembly order. You may
have to tip pump (head upward) in order to keep valve
centered on seat (12) and allow retainer (16) to fit flush
in port.
f. Install manifold (7) and complete installation.
Method #1 Alternative (with system head
pressure less than 2 psi)
a. With pump horizontal, and fluid-end head removed,
remove oil cap (28) and fill reservoir with correct Hydra-
oil. Have catch basin for oil leaks from behind diaphragms
when priming. Catch oil and dispose of properly. Do not
reuse.
b. Force air out of oil in hydraulic cell (behind diaphragms)
by turning shaft and pumping piston. (A shaft rotator
is included in the Wanner Tool Kit.) Keep pressure on
diaphragms while turning shaft until bubble-free flow of
oil comes from behind all diaphragms. Watch oil level
in reservoir. If oil gets too low during priming, air will be
drawn into pistons (inside hydraulic end) and cause pump
to run rough.
c. Quickly attach assembled valve plate (18) (before oil runs
out past diaphragms) with socket head screw (39). Do
not tighten screw completely. Leave gap between valve
plate and cylinder housing (25). Turn shaft 2-3 turns to
force out any remaining air behind diaphragms. Hydraulic
cells are now primed. Complete valve plate installation
with two socket head screws (39) and add pump mani-
fold (7).
d. Wipe off excess oil from around pump head.
e. Check that oil level is 1 inch (25 mm) from top of fill
port.
f. Replace oil cap (28) and complete installation.

20 GH25-991-UK00B
Method #2 (with system head pressure
greater than 2 psi)
NOTE: This simple and clean method of priming the
Hydra-cells requires an inlet head pressure of at least 5
feet (1.5 m) or 2 psi (.14 bar). This pressure is required to
hold the diaphragms back while the piston moves to force
out the air.
a. Completely assemble pump.
b. Remove oil cap (28) and fill reservoir with correct Hydra-oil
to top of fill port.
When tank head pressure is being used to prime, use
the following steps:
c. Install pump in system and connect tank supply line to
pump inlet. Connect pump discharge line. Leave end of
line open to allow air to pass out.
d. Slowly turn pump shaft by hand and watch for bubbles at
oil reservoir fill opening. This will take several rotations.
When no more bubbles come out and reservoir level has
dropped about 1” (25 mm), hydraulic cells are primed.
e. Replace oil cap (28) and complete installation.
When compressed air is being used to prime, use
the following steps:
c. Insert clean air hose to pump inlet and restrict pump
outlet. Turn shaft quarter turn and apply air pressure
into manifold to put pressure on diaphragms. Note air
bubbles at reservoir opening. Repeat for several rotations
until no more air bubbles come out and reservoir level
has dropped about 1” (25 mm). Hydraulic cells are now
primed.
d. Replace oil cap (28) and complete installation.
6. Reinstall Valve Plate (18), and
Manifold (7)
a. Install valve assemblies in valve plate (18) as outlined in
paragraph 2, step e.
b. Install valve plate (18) on cylinder housing (25) with three
cap screws (39).
c.. Reinstall O-rings (8, 9, and 10) between valve plate
and manifold (7). (See illustrations to determine which
O-rings to use depending on pumping head material.)
Use petroleum jelly or lubricating gel to hold them in
place.
d. Reinstall manifold (7) onto valve plate (18). Be sure drain
plug (4) is at bottom of manifold. If pumping head is non-
metallic, support plate (43) is also used.
e. Insert all bolts (5), washers (6), and nuts (31) around
edge of manifold, and centerbolt (1) with washer (2).
Hand tighten.
f. H-25 (external centerbolt models only). Install
centerbolt (1), with washer (2), and tighten. Torque to
60 N-m.
For Model H-25
g. Torque centerbolt to 45 ft-lbs.
h. Alternately tighten opposite bolts (5) until all are secure.
Torque to 45 ft-lbs.
For Model G-25
g. Alternately tighten opposite bolts (5) until all are secure.
Torque to 60 N-m.
h. Torque centerbolt to 60 N-m.
G/H-25 Service (Fluid End)