Ampco ZP3 Series Manual

M-004 Rev G 5.23
Ampco Pumps Company ZP3 Manual
Ampco ZP3 Series
Positive Displacement Pumps
Installation and Maintenance Manual
Original Instructions

Safety Notices
IMPORTANT: Read and understand this manual
BEFORE installation, operation, or maintenance of the
pump. Improper installation, operation, or maintenance
may result in severe injury or death. Equipment damage
caused by user neglect will invalidate the pump
warranty.
Definitions
There are safety symbols used throughout this manual
identifying safety concerns.
DANGER
Indicates a hazardous situation that, if not avoided,
will result in death or serious injury. This applies to
the most extreme situations.
nWarning
Indicates a hazardous situation that, if not avoided,
could result in death or serious injury.
,Caution
Indicates a hazardous situation that, if not avoided,
could result in minor or moderate injury.
Notice
Indicates information considered important, but not
hazard-related (e.g. messages relating to property
damage).
NOTE: Indicates useful, extra information about the
procedure you are performing.
Intended Use
This pump is intended for pumping liquids, especially in
food and beverage applications. Do not use the pump in
any manner that exceeds the specifications that appear
in this manual.
nWarning
Use of this pump in a capacity outside the instructions
in this manual could result in death or serious injury,
along with property damage.
General Safety Instructions
nWarning
• Do not remove safety labels; doing so may result in
injury to users.
• During installation, operation, and maintenance,
keep fingers out of the pump’s ports.
• Follow any provided lifting recommendations when
lifting heavy pumps or components.
• Shut off and lockout all power and relieve system
pressure before servicing to prevent accidental
start-up and injury caused by rotating components.
• Before performing maintenance, make sure the
pump is secured. As components are removed
or added, tipping could occur, resulting in serious
injury.
,Caution
• Only trained personnel should perform installation,
operation, and maintenance.
• After operation, allow the gear case to warm or cool
before handling. Temperatures vary depending on
product.
• Shut off product supply to the pump and drain
the pump before piping disconnection and pump
disassembly.
• During maintenance, handle the rotors, piping, and
other pump components carefully as edges may
be sharp. Wear personal protective equipment
according to the requirements established by
applicable directives.
• Protect hands when in contact with strong cleaning
solutions.
Notice
• Do not rapidly cool or heat the pump.
• Do not run the motor with the pump dry, which
causes damage to pump components.
• Do not obstruct the outlet of the pump, which
results in system pressure above the pump's
specified maximum.
• To avoid damage to metal and seal parts, do not
use abrasive cleaning tools and chemicals.
• Do not use sharp tools to pry components during
disassembly.

Table of Contents
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Safety Notices ................................................................................................................... 2
Definitions......................................................................................................................... 2
Intended Use..................................................................................................................... 2
General Safety Instructions................................................................................................ 2
Section 1
General Information
Introduction ...................................................................................................................... 5
General Information.......................................................................................................... 5
Pump Receiving................................................................................................................. 5
Shipping Damage or Loss................................................................................................... 5
Label Information.............................................................................................................. 6
Section 2
Pump Information
Pump Design ..................................................................................................................... 7
Operating Parameters ....................................................................................................... 7
Section 3
Installation
Installation ........................................................................................................................ 9
Base Arrangement............................................................................................................. 9
Piping and Connections ................................................................................................... 10
Check/Isolation/Relief Valves .......................................................................................... 11
Strainers and Gauges....................................................................................................... 12
Base Alignment ............................................................................................................... 12
Pump Rotation ................................................................................................................ 13
Seal Flushing ................................................................................................................... 14
Pre-Start-Up Checklist ..................................................................................................... 14
Start-Up Procedure.......................................................................................................... 15
Shutdown Procedure....................................................................................................... 15
Emergency Shutdown Procedure..................................................................................... 15
Section 4
Maintenance
Maintenance ................................................................................................................... 17
Pump Lubrication ............................................................................................................ 17
Preventive Maintenance/Inspection................................................................................ 18
Gear and Bearing Inspection............................................................................................ 19
Annual Maintenance ....................................................................................................... 20
Cleaning .......................................................................................................................... 21
Pump Disassembly .......................................................................................................... 21
Seal Maintenance............................................................................................................ 24
Single Mechanical Seal.................................................................................................. 24
Double Mechanical Seal................................................................................................28
Seal Cutaways................................................................................................................ 29
Gear Case Maintenance................................................................................................... 30
Disassembly .................................................................................................................. 30
Assembly ....................................................................................................................... 32
Pump Assembly............................................................................................................... 37
Pump Clearances............................................................................................................. 41

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Ampco Pumps Company ZP3 Manual
Table of Contents (continued)
Ampco Pumps Available Options .................................................................................... 42
Vented Cover (Pressure Relief)...................................................................................... 42
Jacketed Cover .............................................................................................................. 42
Section 5
Troubleshooting
Troubleshooting .............................................................................................................. 43
Section 6
Appendix
PD Pump Remanufacturing Program................................................................................ 45
ATEX Certification Information ........................................................................................ 45
Terms and Conditions ...................................................................................................... 49
Return Policy ................................................................................................................... 51
Credits ........................................................................................................................... 51

M-004 Rev G 5.23
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Introduction
To ensure the best results and service, please read and
fully understand this manual prior to putting this pump
into service. For any questions regarding operation,
maintenance, or installation, please contact your local
distributor or Ampco Pumps Company:
Ampco Pumps Company
2045 W. Mill Road, Glendale, WI 53209
Phone: [phone] or [phone]
Fax: [phone]
Email: [email protected]
General Information
Each Ampco ZP3 pump is fully assembled, lubricated,
and tested at the factory and shipped ready for use.
Standard maintenance practices are outlined in this
manual. For more information, please refer to the
Maintenance section on page 17. Following these
guidelines will provide long-lasting, trouble-free
service when the pump(s) is incorporated in a properly
designed system.
Pump Receiving
Ampco covers the pump inlet and discharge ports prior
to shipping, ensuring that foreign matter does not enter
the pump during shipment. If the protective covers
are missing upon arrival, remove the pump cover and
inspect to ensure it is free from contaminate before
turning the shafts. Please make note of the pump
serial number; this will assist in the process of ordering
replacement parts and/or a warranty claim. For more
information regarding shipment damage or warranty,
please refer to Terms and Conditions (page 49).
Shipping Damage or Loss
Upon receiving equipment that is damaged or if your
shipment is lost in transit, immediately file a claim with
the carrier. At time of pick-up, the carrier signed the bill
of lading, acknowledging that they have received the
product from Ampco in good condition.
Section 1
General Information

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General Information Section 1
Label Information
nWarning
Labels are installed on the pump at the factory to
ensure proper warning to users.
Do not remove these labels; doing so may result in
injury.
The pump is installed with simple, but effective labels to
help the customer better understand the ZP3 pump. An
identification plate is applied at the factory to help track
the life of the pump. The customer should be aware of
the pump’s serial number and model number prior to
contacting Ampco with any concerns. These labels can
be seen in Figure 1.
Figure 1. Important Label Information

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Ampco Pumps Company ZP3 Manual
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Pump Design
The design of the ZP3 pump gear case allows for the
shaft location to be universal in order to fit any system
requirement. This can be seen in Figure 2 and Figure 3.
Figure 2. Shaft Mounts (Upper and Lower)
Figure 3. Shaft Mounts (Left and Right as Viewed from the Front)
Operating Parameters
Table 1. Standard Operating Parameters
Model
Maximum
Nominal
Capacity
Displacement
Maximum
Differential
Pressure
Temperature
Range
Standard
Connection
Size
Optional
Connection
Size
Maximum
Speed
GPM m3/hr Gal./
100 rev
Liters/
rev PSI Bar ° F ° C in. mm in. mm RPM
ZP3 6 8 1.8 0.8 0.030 300 21
-40°
to
200°
-40°
to
93°
1.5 38 1.0 25 1000
ZP3 15 11 2.5 1.4 0.052 250 17 1.5 38 - - 800
ZP3 18 20 4.5 3.0 0.108 200 14 1.5 38 2.0 51 700
ZP3 30 36 8.2 6.0 0.227 250 17 1.5 38 2.0 51 600
ZP3 40 46 10.4 7.6 0.288 150 10.3 2.0 51 2.5 64 600
ZP3 45 58 13.2 10.0 0.366 450 31 2.0 51 - - 600
ZP3 60 90 20.4 15.0 0.568 300 21 2.5 64 3.0 76 600
ZP3 130 150 34.1 25.0 0.946 200 14 3.0 76 4.0 102 600
ZP3 180 230 52.2 38.0 1.450 450 31 3.0 76 - - 600
ZP3 210 300 68.1 50.0 1.900 500 34 4.0 102 - - 600
ZP3 220 310 70.4 52.0 1.980 300 21 4.0 102 - - 600
ZP3 320 450 102 75.2 2.847 300 21 6.0 152 - - 600
Section 2
Pump Information

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Pump Information Section 2
Table 2. Rectangular Flange Model Operating Parameters
Model
Maximum
Nominal
Capacity
Displacement
Maximum
Differential
Pressure
Temperature
Range
Rectangular
Inlet
(W x L)
Outlet Maximum
Speed
GPM m3/hr Gal./
100 rev
Liters/
rev PSI Bar ° F ° C in. in. mm RPM
ZP3 34 24 5.4 6.0 0.22 250 17
-40°
to
200°
-40°
to
93°
1.75 x 6.75 2.0 50 400
ZP3 64 60 13.6 15.0 0.57 300 21 2.24 x 8.82 2.5 65 400
ZP3 134 100 22.7 25.0 0.96 200 14 2.97 x 9.25 3.0 76 400
ZP3 184 152 34.5 38.2 1.43 450 31 3.28 x 11.25 3.0 76 400
ZP3 214 200 45.4 50.2 1.90 500 34 3.45 x 12.70 4.0 102 400
ZP3 224 208 47.2 52.1 1.97 300 21 3.87 x 11.00 4.0 102 400
ZP3 324 401 91 75.2 2.75 300 21 4.25 x 12.70 6.0 152 400
• For operating parameters that fall outside the
standard values defined in Table 1 and Table 2,
please contact the Engineering Department at Ampco
Pumps Company (414-643-1852).
• Standard rotors operate within a temperature range
of -40°F to 200°F. Hot clearance rotors operate
between 180°F to 300°F. Consult Ampco for
questions on application factors such as temperature,
operational speed, and differential pressure.
,Caution
Noisy pump operation may result from cavitation, air/
gas in product, rotor to body contact, rotor to rotor
contact, or external mechanical problems. See the
Troubleshooting section, under “Noisy Operation” for
corrective measures that may be taken to avoid injury
from excessive sound pressure. Wear ear protection
when levels may exceed 80 dBA.

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Installation
Follow local codes and restrictions when installing the
pump and piping system. The practices outlined in
this manual are intended to ensure the most optimal
performance of the pump.
,Caution
Use vibration isolation pads to reduce noise and
vibration. Failure to reduce vibration as needed could
cause minor or moderate injury.
Base Arrangement
The standard installation arrangement for a pump
of this type consists of both the pump and drive unit
mounted on the same base plate. Typical base plate
arrangements consist of permanently fixed bases,
bases with leveling and/or vibration isolation pads,
bases with attached adjustable legs, or portable/
wheeled bases. All base arrangements must be level
during operation. Standard base configurations (base,
pump, coupling, coupling guard, gear reducer, and
motor) can be seen in Figure 4.
Permanently Fixed Leveling/Isolation Pads
Adjustable Legs Portable/Wheeled
Guard
Figure 4. Base Layout Examples
nWarning
To ensure safety, protective guards must be
properly installed over all external rotating parts and
components. Failure to do so may result in injury.
Ampco provides protective guards for complete base
packages (pump and drive unit).
Section 3
Installation

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Ampco Pumps Company ZP3 Manual
Installation Section 3
Piping and Connections
It is important to minimize forces imposed on the pump.
This can be done by independently supporting the
piping going to and from the pump. Excessive force
applied to the pump can cause misalignment of internal
parts which leads to the premature wear of rotors,
bearings, and shafts. The use of hangers and pedestals
on connecting pipes will help avoid such misalignment.
Examples of such supports can be seen in Figure 5.
Figure 5. Piping Support Example
It is not recommended to weld custom fittings outside
the factory. Shrinkage and warpage can occur to the
pump housing which will affect the life and performance
of the pump.
To prevent air pockets from entering the pump from the
inlet, install the pump below the supply (Figure 6). This
will create a constant supply of product on the suction
side, and reduce the chance for air to enter the pump.
Sloping the piping on the inlet side away from the pump
will prevent air pockets if the pump is installed above
the supply (Figure 7).
Figure 6. Correct Piping (Supply Above)
Always verify all electrical devices connected to the
equipment are properly grounded to avoid risk of
potential corrosion from stray current.
Figure 7. Correct Piping (Supply Below)

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Section 3 Installation
Check/Isolation/Relief Valves
Check valves should be used on the inlet side for any
application when the product is lifted (Figure 8). This is
to ensure a full inlet and is especially important with low-
viscosity fluids. If the system has liquid under a vacuum,
such as closed tank applications, it is important to have
a check valve on the discharge side to prevent backflow
during initial start-up (Figure 9).
Check Valve
Foot Check Valve
Figure 8. Check Valve (Inlet Side)
Check Valve
Closed Tank
Figure 9. Check Valve (Discharge Side)
When shutdown time is not possible, a bypass system
may be installed with a backup pump in parallel series
to allow production to continue while maintenance is
performed on the down pump. Isolation valves may
also be used on both the inlet and discharge sides of
the pump to shut down the flow of product to the pump.
This will allow for maintenance and removal of the pump
without draining the entire system and risking the loss of
product.
Notice
Ampco’s ZP positive displacement pumps are
designed with extremely tight tolerances allowing
only low slip internally between rotors and pump
housing. DAMAGE will occur if the pump is operated
with discharge or inlet lines closed. DO NOT operate
pump with lines closed.
In order to prevent damage to the pump, it is
recommended a relief valve be installed on the pump’s
discharge side. The relief valve can either divert flow
into a drain or back to the inlet side (Figure 10).
Figure 10. Relief Valve Examples

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Installation Section 3
Strainers and Gauges
Strainers and magnetic traps should be used to prevent
foreign matter from entering the pump. It is essential
to service strainers and traps regularly to prevent
restriction of flow. To determine the performance of the
pump, install pressure and vacuum gauges on the inlet
and discharge piping (Figure 11).
Proper Gauging Shows:
• Unusual pressure variations
• Indicates flow
• Changes in pump performance
• Variations in the system
• Differences in fluid viscosities
Figure 11. Proper Gauging
Base Alignment
Pump and base assemblies sent directly from Ampco’s
factory are aligned prior to shipment. Assemblies
must be checked once they are installed and prior to
operation. Misalignment may cause unnecessary wear
and shorten the life of the pump. If couplings are not
specified, Ampco will use a flexible coupling which
permits minor compensation for alignment and endplay.
To check the coupling alignment, start with checking the
angular alignment by measuring the gaps between the
couplings on both the pump and motor side (Figure 12,
Angular Alignment). Shim the assembly accordingly
so the gap is equal distance at all points. Next, using
a straight edge, check the horizontal and vertical
alignment of the coupling. Place the straight edge along
the coupling to ensure that both sides are concentric
(Figure 12, Parallel Alignment).
Angular Alignment Parallel Alignment
Straight Edge
Figure 12. Check Alignment

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Section 3 Installation
Pump Rotation
Check the direction of rotation (both on drive unit and
pump) prior to connecting the pump to the drive. This
will ensure correct product flow at start-up (Figure 13
and Figure 14). Also check that the pump turns freely
and is free of any foreign contaminates. Connect the
pump and check to make certain all guards are in place.
Figure 13. Top Drive Shaft
Figure 14. Bottom Drive Shaft

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Installation Section 3
Seal Flushing
For pumps with double seals, connect seal flushing
before operation. Operation of the pump without proper
flushing will damage seal faces. Flushing connections
are typically 1/8" female NPT with one side being the
inlet and the other the discharge. Flush from the bottom
to the top, using the lower connection as the inlet and
the upper connection as the discharge. This ensures
that air is removed from the flush line with the flush
area completely flooded (Figure 15). Flush flow rate
should be 1/4 GPM (30 psi max pressure). For high
temperature applications flush flow may be increased to
remove excess heat.
ZP3 is capable of a barrier pressure no more than
10-15 psi above the process pressure. Keep in mind a
small amount of the barrier fluid will enter the pumped
liquid, therefore the barrier fluid must be compatible with
the product.
*Maximum Barrier Pressure is 100 psi
Flush In
Flush Out
Figure 15. Proper Flushing for ZP3 Double Seal
Pre-Start-Up Checklist
,Caution
DO NOT flush a new system for the first time with
this pump. Severe damage may be caused to the
pump from debris during start-up, which could result
in injury. Remove the rotors during system flushing
to prevent any debris from getting trapped between
rotors and pump body.
nWarning
All guards must be installed to protect operators
and maintenance personnel from the rotating
components. Guards are supplied as part of pump
and motor full assemblies. The gap between the
pump body and gearcase is required for 3-A sanitary
standards.
nWarning
Do not start a pump with a seal flush unless the seal
flush is installed and on.
1. Review setup and make sure the pump is correctly
installed as described in Section 3 “Installation” on
page 9. Review “Check/Isolation/Relief Valves”
on page 11 and install valves as needed.
2. Check the coupling alignment. See base and
coupling alignment on page 12.
3. Check the pump and piping and make sure they are
clean and free of any foreign material.
4. Make sure that all piping connections are secure
and leak-free. If possible, checking the system with
non-hazardous fluid like water is advisable.
5. Double check the pump and drive to see if they are
adequately lubricated. See “Pump Lubrication” on
page 17.
6. Check that all guards are secured properly and in
place.
7. Ensure double mechanical seals have proper
supply and flow of clean fluids when flushing.
8. Make sure all valves are open on INLET side and
allow fluid to fill the pump. Flooding the suction is
recommended on installation.
9. Discharge side valves should be open and free of
obstructions.
10. Check the pump and drive rotation to verify
the correct product flow at start-up. See “Pump
Rotation” on page 13.

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Section 3 Installation
Start-Up Procedure
nWarning
Pump damage could result in death or serious injury.
• Do not run the motor with the pump dry, which
causes damage to pump components.
• Do not obstruct the outlet of the pump. Obstruction
will result in increased system pressure, above the
specified maximum pressure of the pump.
• Do not introduce sudden extreme product
temperature changes to the pump (temp flashing).
Gradually adjust the temperature of the pump
components or the product.
NOTE: Sanitize the pump before start-up for sanitary
applications.
1. Start the pump slowly.
2. When the pumphead is filled with product, stop
the pump and allow the pump’s fluid components
to thermally adjust to the product temperature for
15 minutes.
3. Re-start the pump.
Shutdown Procedure
1. Disconnect the pump from the drive.
2. Disconnect the supply and discharge lines.
Emergency Shutdown Procedure
Emergency Shutdown is dependent on system
requirements. Document the procedure after
assessment of the application.

16 M-004 Rev G 5.23
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Installation Section 3
THIS PAGE INTENTIONALLY LEFT BLANK

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17
Maintenance
nWarning
Shut off and lockout all power and relieve system
pressure before servicing to prevent accidental
start-up and injury.
nWarning
Make sure the pump is secured prior to performing
maintenance. As components are removed or added,
tipping could occur.
,Caution
Only trained personnel should perform maintenance.
The Ampco ZP3 pump is designed to be easily
disassembled for cleaning and maintenance purposes.
When performing maintenance on the pump it is
important to inspect all wetted parts for standard wear
and damage. For inspection instructions please see
page 18. For rebuild information, see PD Pump
Remanufacturing Program details on page 41. Prior
to disconnecting pump, shut off all inlet and discharge
valves, drain the pump (rinse if necessary), and turn off
all electrical supply to the pump (follow standard lockout
procedures).
Pump Lubrication
Proper lubrication of gears and bearing is vital to the
life of the pump. For pumps assembled on bases with
a gear reducer and motor, please refer to the proper
manufacturer manual for lubrication requirements.
These manuals are sent with the pump from the factory.
Important pump lubrication points can be seen in
Figure 16.
A
B
B
D
A
A
B
B
C
D
A
Figure 16. Lubrication Points
Item No. Part Qty.
A Clean-out Plugs 4
B Oil Plug (Drain and Fill) 5
C Sight Glass 1
D Grease Fittings 8
Both gears and bearing are shipped factory-lubricated
with grease and oil. The oil used to lubricate the gears
should be changed every 500 hours with the quantities
shown in Table 3. The bearings should be re-greased
every 250 hours. Excessive grease may build up inside
the gear case and should be cleaned out through the
clean-out plugs shown in Figure 16, A.
Section 4
Maintenance

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Maintenance Section 4
Table 3. Oil Capacity (Gears) and Grease Quantity (Per
Bearing)
ZP3 Model
Oil Capacity
(Gears)
Grease Quantity
(Per Bearing)
Top/
Bottom
Shaft
Side
Mount Front Rear
6, 15, 18 1.3 oz
(40 ml)
3.3 oz
(100 ml)
0.37 oz
(11 cc)
0.13 oz
(4 cc)
30, 34, 40 2.0 oz
(60 ml)
4.0 oz
(120 ml)
0.60 oz
(18 cc)
0.21 oz
(6 cc)
45, 60, 64,
130, 134
6.0 oz
(170 ml)
9.5 oz
(280 ml)
0.84 oz
(25 cc)
0.76 oz
(22 cc)
180, 184,
220, 224
11 oz
(320 ml)
20 oz
(600 ml)
1.33 oz
(39 cc)
1.03 oz
(30 cc)
210, 214,
320, 324
17 oz
(500 ml)
44 oz
(1300 ml)
1.96 oz
(58 cc)
1.16 oz
(34 cc)
Oil Specifications:
ISO Grade 320, SAE 140 or AGMA Number 6EP
Grease Specifications:
Halo-Guard FG-2, NSF H1 FOOD-GRADE, NLGI Grade
No. 2
*Replacement oil and grease is available from Ampco.
Preventive Maintenance/Inspection
,Caution
Handle the rotors, piping, and other pump
components carefully as edges may be sharp. Wear
gloves to avoid injuries.
While performing standard maintenance or cleaning,
check for signs of damage or extreme wear. A simple
inspection may show signs of a problem long before it
becomes serious. Detection of such problems can avoid
costly repairs and reduce down time.
Remove the cover and inspect the rotor tips to ensure
that there is no metal-to-metal contact between the
rotors. Measure the clearance between the rotor tips
as seen in Figure 17. The clearance should be equal
on both sides. If contact is detected, rotors may require
replacement.
Clearance should
be equal
Figure 17. Clearance Between Rotor Tips
Inspect the shaft shoulder and shaft keyway (Figure 18)
for wear and replace, if necessary.
Shaft Shoulder
Shaft Keyway
Figure 18. Shaft Inspection Points
Inspect the rotor hub and rotor keyway (Figure 19) for
wear and replace, if necessary. Rotor and shaft wear at
these locations is caused by extended operation with
loose rotor nuts.
Rotor Keyway
Rotor Hub
Figure 19. Rotor Inspection Points

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Section 4 Maintenance
Gear and Bearing Inspection
,Caution
Temperatures may vary depending on product. To
avoid injury, allow the gear case to warm or cool
before handling.
While the fluid end is disassembled, feel for gear
backlash (play between the gears) by rotating either
shaft. Once turning has started the other shaft must
engage (Figure 20). If gear backlash is present remove
the gear casing cover (drain oil first, see page 30 for
disassembly information) and check for wear around
the gear teeth. If evidence of gear teeth wear is present,
replacement is recommended. If gear(s) are loose,
check the shaft key and keyway, either may require
replacement.
Figure 20. Check for Gear Backlash
Next, check the condition of the bearings. Do this by
applying force in an up-and-down motion by hand on
both shafts (Figure 21). Also check for any horizontal
movement by pushing and pulling on the shaft. If any
movement is felt, the bearing may need replacing. If
disassembly of the entire gear case is required, please
refer to page 30 for instructions.
Figure 21. Check for Bearing Movement

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Maintenance Section 4
Annual Maintenance
,Caution
Handle the rotors, piping, and other pump
components carefully as edges may be sharp. Wear
gloves to avoid injuries.
,Caution
Temperatures may vary depending on product. To
avoid injury, allow the gear case to warm or cool
before handling.
It is important to perform an annual maintenance check
of the pump in addition to the preventive maintenance
procedures listed on page 18. Annual maintenance
practices are as follows:
• Check the gear case bearings by measuring
the shaft’s radial movement with a dial indicator
(Figure 22, A). If the movement is greater than
or equal to the rotor-to-body clearance found on
page 41 (Table 10) the bearings should be
replaced.
• Remove the gear casing cover (see page 30 for
disassembly information) and inspect the gears for
wear and damage (Figure 22, B). Also check for
backlash and looseness.
• Inspect the rotors for signs of wear and stress cracks
around the areas defined in Figure 22, C. Replace, if
necessary.
• Check the pump clearances detailed on page 41
to determine pump wear. Pump wear can be
compensated by increasing pump speed.
Check Gears
B
A
Check Bearings
C
Check Rotors
Figure 22. Annual Maintenance Checks