LMI G Series User manual

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InstructionInstruction
InstructionInstruction
Instruction ManualManual
ManualManual
Manual
Series G, Model B
Motor-Driven Pump
For file reference, please record the following data:
Model No:
Serial No:
Installation Date:
Installation Location:
When ordering replacement parts for your LMI Pump, please include the complete
Model Number and Serial Number of your unit.
Replace same of 1784 Rev. A 1/98
1784 B. 12/99
8 Post Office Square
Acton, MA 01720 USA
TEL: [phone]
FAX: [phone]
http://www.Imipumps.com

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Table of Contents
1.0. Description ............................................................................................................................................... 3
1.2 Principle of Operation .............................................................................................................................. 3
1.3 General Specifications...................................................................................................................... 3
1.4 Product Code.................................................................................................................................... 4
2.0. Installation ................................................................................................................................................ 5
2.1 Unpacking......................................................................................................................................... 5
2.2 Safety precautions............................................................................................................................ 5
2.3 Storage ............................................................................................................................................. 5
2.4 Handling of Pump............................................................................................................................. 5
2.5 Mounting ........................................................................................................................................... 6
2.6 Piping ................................................................................................................................................ 6
2.7 Leak Detection.................................................................................................................................. 9
2.8 Electrical Connections...................................................................................................................... 9
3.0 Operation.................................................................................................................................................. 9
3.1 Initial Start-Up ................................................................................................................................... 9
4.0 Maintenance........................................................................................................................................... 10
4.1 Spare Parts ..................................................................................................................................... 10
4.2 Shipping Pumps for Repair ............................................................................................................ 11
4.3 Preventive Maintenance ................................................................................................................. 11
4.4 Corrective Maintenance.................................................................................................................. 12
5.0 Troubleshooting Guide .......................................................................................................................... 16
5.1 Symptoms & Remedies.................................................................................................................. 16
6.0 Parts (Figures 7 through 14).................................................................................................................. 18
7.0 Parts Lists ............................................................................................................................................... 23
7.1 Basic Parts List ............................................................................................................................... 23
7.2 Check Valve Parts List .................................................................................................................... 24
8.0. Statement of Limited Warranty .............................................................................................................. 27
WARNING
A PRESSURE RELIEF VALVE WITH A RELIEF PRESSURE OF 25 PSI (1.7 BAR)
ABOVE RATED PUMP PRESSURE AND A RELIEF FLOW (BLEED) RATE
ADEQUATE FOR RATED PUMP OUTPUT (PULSATING) MUST BE INSTALLED IN
THE DISCHARGE LINE OF THIS PUMP.
Dis harge piping should have a minimum burst pressure of 600 psi (41 Bar).
Failure to provide pressure relief may result in failure modes dangerous to the
system, asso iated piping, the pump itself and operating personnel.
CAUTION
!
CAUTION
!

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1.0 Description
1.1 General
The Series G, Model “B” pumps are reciprocating, chemical dosing pumps capable of producing controlled flows up to 31 gallons
per hour (1175 l/h) at pressures up to 15 psi (1 Bar) (depending on the model). These pumps feature a mechanically actuated
diaphragm, which eliminates the need for contour plates, and a stroke adjustment mechanism based on the variable eccentric principle
instead of the traditional lost motion design. This design substantially reduces pressure and flow pulsations contributing to an increase
in the life of system components and more continuous chemical injection. It is designed for industrial service and offers an accuracy
of ± 2% of 1 % rated flow between 1 % and 1 % of its flow range.
1.2 Principle of Operation
The pump consists of two (2) major assemblies; the drive and the liquid end. Pump delivery is a function of the drive’s stroke rate, liquid
end size and stroke length. Stroke length can be adjusted while the pump is running or stopped by turning the stroke adjusting knob.
The drive motor transmits rotary motion to a worm gear speed reduction unit which in turn drives the variable eccentric crank. The
adjustable crank imparts reciprocating motion to the diaphragm through an interposing connecting rod. The stroke length is adjusted
by changing the position of the variable eccentric crank in the connecting rod assembly.
As the Liquifram™ starts back on the suction stroke, the pressure immediately drops inside the liquid end. When the liquid end pressure
drops below the suction line pressure, the suction ball check is “pushed” upward and the process fluid in the suction line flows into the
liquid end chamber. When the suction stroke ends, the Liquifram™ movement momentarily stops. The pressure in the liquid end
equalizes with the pressure in the suction line and the suction ball check seats.
It is important that the pressure in the liquid end remain above the vapor pressure of the process fluid during
the suction stroke. If the fluid pressure drops below the vapor pressure, cavitation will occur, negatively
impacting the performance of the pump. If you suspect the possibility of cavitation, contact an LMI Master
Distributor for assistance.
As the diaphragm starts forward on the discharge stroke the pressure immediately rises inside the liquid end. When the liquid end
pressure rises above the discharge line pressure, the discharge ball check is “pushed” upward and the process fluid in the liquid end
flows into the discharge line. When the discharge stroke ends, the diaphragm momentarily stops again. The pressure in the liquid end
equalizes with the discharge line pressure and the discharge ball check reset. The cycle then starts again.
1.3 General Specifications
Flow Rate........... Up to 31 GPH (1175 l/h)
Pressure ............. Up to 15 PSI (1 Bar)
Design................. Mechanically Actuated Liquifram™
Drive................... Variable Eccentric
A ura y ............ ± 2% of 1 % rated flow between 1 % and 1 % of rated flow
Adjustment ........ Lockable micrometer is adjustable from % to 1 % while pump is running or stopped
Lubri ation ........ Oil bath
Temperature...... Ambient and Liquid: 122º F (5 º C) Maximum, 14º F (-1 º C) Minimum
Su tion Lift ........ 8.2 ft (2.5 m) of water column maximum. 11 PSI minimum internal pressure (4 PSI Max. Vacuum)
Paint ................... Two-part epoxy, yellow RAL 1 18

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1.4 Product Code
Series G Pumps are available in a variety of different configurations. For a breakdown of the options included in a specific pump,
compare the pump model number and product code found on the pump nameplate with the model/product code breakdown shown in
Figure 1. A sample dataplate is shown in Figure 2.
Figure 2: Sample Dataplate
Figure 1: Model/Product Code
Liquid End Connections
No. Head / Fittings Inch Metric
Model G51 8 - 541P
541P Polypropylene/PVC 1/2" NPT F
541Q Polypropylene/PVC DN15
542P PVDF 1/2" NPT F
542N PVDF 1/2" BSP F
547P 316 SS 1/2" NPT F
547N 316 SS . 1/2" BSP F
548P PVC 1/2" NPT F
548Q PVC DN15
561P Polypropylene/PVC 1" NPT F
561Q Polypropylene/PVC DN25
562P PVDF 1" NPT F
562N PVDF 1" BSP F
567P 316 SS 1" NPT M
567N 316 SS 1" BSP M
568P PVC 1" NPT F
568Q PVC DN25
581P Polypropylene/PVC 1" NPT F
581Q Polypropylene/PVC DN25
582P PVDF 1" NPT F
582N PVDF 1" BSP F
587P 316 SS 1" NPT M
587N 316 SS 1" BSP M
588P PVC 1" NPT F
588Q PVC DN25
Output Code(1)
G51...... 29 GPH @ 60 Hz (92 l/h @ 50 Hz) ....150 psi (10.0 Bar)
G52...... 58 GPH @ 60 Hz (184 l/h @ 50 Hz) ..150 psi (10.0 Bar)
G53...... 116 GPH @ 60 Hz(366 l/h @ 50 Hz) ..150 psi (10.0 Bar)
G58(2) ...................................................... (457 l/h @ 50 Hz) .............. (10.0Bar)
G63...... 155 GPH @ 60 Hz(488 l/h @ 50 Hz) ..100 psi . (7.0 Bar)
G68(2) ...................................................... (610 l/h @ 50 Hz) ................ (7.0 Bar)
G73...... 310 GPH @ 60 Hz(1000 l/h @ 50 Hz) ..50 psi . (3.5 Bar)
G78(2) ...................................................... (1250 l/h @ 50 Hz) .............. (3.5 Bar)
Motor
8 .......3/4 hp, 1-Phase, 60 Hz, 115/230 V, 1800 rpm,
TEFC, 56C Frame
K .......0.55 kW, 3-Phase, 50 Hz, 220/380 V, 1500 rpm,
TEFC, F165 Flange, 80 Frame
J .......3/4 hp, 3-Phase, 60 Hz, 230/460 V, 1800 rpm,
TEFC, 56C Frame
H.......AC Variable Speed Motor
P .......DC Variable Speed Motor
N.......No Motor (IEC 80 Frame, F165 Flange)
X .......No Motor (56C Frame)
(1) Outputs are at nominal 22 psi (1.5 Bar)
(2) Available only with 5 Hz motor

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2.0 Installation
2.1 Unpacking
Pumps are shipped f.o.b. factory or distributor warehouse and the title passes to the customer when the carrier signs for receipt of the
pump. In the event that damages occur during shipment, it is the responsibility of the customer to notify the carrier immediately and
to file a damage claim.
Carefully examine the shipping carton upon receipt from the carrier to be sure there is no obvious damage to the contents. Open the
carton carefully so accessory items inside will not be damaged or lost. Examine all material and check against packing list to be sure
that all items are accounted for and intact.
2.2 Safety Precautions
When installing, operating, and maintaining the Series G Pump, keep safety considerations foremost. Use proper tools, protective
clothing, and eye protection when working on the equipment and install the equipment with a view toward ensuring safe operation.
Follow the instructions in this manual and take additional safety measures appropriate to the liquid being pumped. Be e tremely careful
in the presence of hazardous substances (e.g., corrosives, to ins, solvents, acids, caustics, flammables, etc.).
2.3 Storage
Temporary Storage (Less than 6 Months)
It is preferable to store the material under a shelter in its original package to protect it from adverse weather conditions. In condensing
atmospheres, follow the long term storage procedure.
Long Term Storage (Longer than 6 Months) Primary Considerations
The primary consideration in storage of pump equipment is to prevent corrosion of external and internal components. This corrosion
is caused by natural circulation of air as temperature of the surroundings change from day to night, day to day, and from season to season.
It is not practical to prevent this circulation which carries water vapor and other corrosive gasses, so it is necessary to protect internal
and external surfaces from their effects to the extent possible.
When the instructions given in this section are completed, the equipment is to be stored sheltered; protected from direct exposure to
weather. The prepared equipment should be covered with a plastic sheet or a tarpaulin, but in a manner which will allow air circulation
and prevent capture of moisture. Equipment should be stored 12 inches or more above the ground.
Pump Drive
1. Flood the gearbox compartment with a high grade lubricating oil/rust preventative such as Mobile Oil Corporation product
“Mobilarma 524.” Fill the compartment completely to minimize air space and water vapor condensation. After storage, drain this
material and refill the equipment with the recommended lubricant for equipment commissioning.
2. Remove drive motor and liquid end, and brush all unpainted metal surfaces with multipurpose grease (NLGI grade 2 or 3). Store
these unattached.
Ele tri al Equipment
1. Motors should be prepared in the manner prescribed by their manufacturer. If information is not available, dismount and store
motors as indicated in step 3 below.
2. Dismount electrical equipment (including motors) from the pump.
3. For all electrical equipment, place packets of Vapor Phase Corrosion Inhibitor (VPCI) inside the enclosure, then place the entire
enclosure, with additional packets, inside a plastic bag. Seal the bag tightly closed.
2.4 Handling of Pump
To avoid damaging the pump while moving or installing a Series G Pump, follow the instructions below. Refer to Figure 3.
1. Place a sling under the motor flange.
2. Cross the two ends of the sling and close the loop.
3. Place the other end of the sling under the liquid end mounting flange.
4. Make sure the entire unit is well balanced before attempting to move the pump.
To avoid possible damage to either pump or personnel, bolt pump down as soon as it is in position.
CAUTION
!

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2.5 Mounting
Support the pump firmly in a level position on a solid, vibration-free foundation, preferably with the base above floor level to protect
the pump from wash downs and to provide easier access for service. Be sure to allow enough space around the pump for easy access
during maintenance operations, pump adjustments, and/or oil filling or draining procedures.
Series G Pumps are provided with mounting holes to accommodate anchor bolts. Refer to Figure 4 for mounting hole dimensions.
Some Series G Pumps are shipped with motors dismounted. After anchoring pump in position, install motor, referring to Figure 7. Make
sure spring (360) provided with pump is installed in worm shaft prior to motor installation.
Pumps installed outdoors should be protected by a shelter.
2.6 Piping
NPSH Considerations
Size piping to accommodate peak instantaneous flow. Because of the reciprocating motion of the pump diaphragm, pump delivery
follows an approximate sine curve with a peak instantaneous flow pi (3.14) times the average flow. Therefore, piping must be designed
for a flow 3.14 times the pump capacity; this means that a pump rated for 88 gallons per hour (333 l/h) requires piping sufficient for
3.14 x 88 gph, or 276 gph (1 45 l/h).
To minimize viscous flow losses when handling viscous liquids, it may be necessary to use suction piping up to four times larger than
the size of the suction connection on the pump. If in doubt, contact your nearest LMI Master Distibutor to determine the necessary pipe
size.
General Piping Considerations
• Use extreme care in piping to plastic liquid end pumps with rigid pipe such as PVC. If excessive stresses or vibration is unavoidable,
flexible connections are recommended.
• Use piping materials that will resist corrosion by the liquid being pumped. Use care in selecting materials to avoid galvanic
corrosion at pump liquid end connections.
• Use piping heavy enough to withstand maximum pressures.
• Remove burrs, sharp edges, and debris from inside piping. Blow out all pipe lines before making final connections to pump.
• Because vapor in the liquid end will cause inaccurate pump delivery, piping should be sloped to prevent vapor pockets.
• When pumping suspended solids (such as slurries), install plugged crosses at all 9 ° line turns to permit line cleaning without
dismantling piping.
• See Figure 5 for a typical recommended pump installation scheme.
Figure 4: Mounting Hole Dimensions
9”
(228.6 mm)
4½”
(114.3 mm)
0.354” (9 mm) Dia.
Mounting Holes
Motor
C
L
Liquid End C
L
Figure 3: Handling a Series G Pump

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Figure 5: Typical Recommended Pump Installation Scheme
Safety
Valve
Vent
Pulsation
Dampener
Pressure
Gauge Back
Pressure
Valve
Metering
Pump
= Shut off Valve
Calibration
Column
To Drain
Prime/Air
Purge Valve
Pulsation
Dampener
Supply Tank To Injection
Point
Strainer
Su tion Piping Considerations
• It is preferable to have the suction of the pump flooded by locating the liquid end below the lowest level of the liquid in the supply
tank. Installing the supply vessel on the suction line close to the pump can help ensure a flooded suction line.
• Avoid negative suction pressure conditions (suction lift), as such conditions adversely affect metering accuracy. A lift of 8.2 ft
(2.5 m) of water column is the maximum suction lift permissible.
• Series G Pumps are designed to operate with process liquid supplied at or above atmospheric pressure. Although these pumps can
move liquids supplied at less than atmospheric pressure, in these negative pressure applications it is important that all connections
be absolutely drip free and vacuum tight, and that a foot valve be installed at the bottom of the suction line (see Figure 6).
• When pumping a liquid near its boiling point, provide enough suction head to prevent the liquid from “flashing” into vapor when
it enters the pump liquid end on the suction stroke.
• If possible use metal or plastic tubing for the suction line because tubing has a smooth inner surface and can be formed into long,
sweeping bends to minimize frictional flow losses.
• A strainer should be used in the suction line to prevent foreign particles from entering the liquid end. This and any other measures
which prevent debris from entering and fouling the ball-checks will give increased maintenance-free service. Check strainer
frequently to prevent blockage which could lead to cavitation.
• Keep suction piping as short and straight as possible.
• Piping size should be larger than the liquid end suction fitting to prevent pump starvation.
• If long suction lines are unavoidable, install a stand pipe near the pump in the suction line.
• Suction piping must be absolutely airtight to ensure accurate pumping. After installation, test suction piping for leaks with air and
soap solution.
Dis harge Piping Considerations
• Install pipe large enough to prevent excessive pressure losses on the discharge stroke of the pump. Maximum pressure at the
discharge fitting on the liquid end must be kept at or below the rated pressure (maximum allowable working pressure shown on
the pump dataplate).
• The pump will not deliver a controlled flow unless the discharge line pressure is 1 psi (.7 Bar) greater than the suction line pressure.
There are a number of ways to create an artificial pressure, such as by installing a back pressure valve.
• When pumping water-treatment chemicals directly into boiler drums, use one liquid end assembly for each boiler drum.
Discharging into a manifold having the slightest pressure difference between its several discharge connections can diminish
metering accuracy as the outlet with the lowest pressure will receive more liquid than the other outlets.

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Metering
Pump
Supply
Tank
Foot
Valve
6”
(152 mm)
Ba k Pressure Valves
An LMI Back Pressure Valve should be installed in the discharge line near the pump to ensure sufficient discharge head pressure for
proper pump metering action. Normally, the valve should be located near the pump; however, back pressure valves for large pumps
with long and extremely small discharge lines may have to be installed near the point of discharge into the process (to minimize
siphoning tendencies).
Pulsation Dampeners
An accumulator, surge chamber, surge suppressor, or pulsation dampener should be used with the back pressure valve in the discharge
line to absorb the flow peaks between the pump and the back pressure valve. Without the pulsation dampener the valve mechanism will
snap open and closed with the surge from each pump stroke. The pulsation dampener will allow the back pressure valve to oscillate
about a partly-closed position, thus minimizing wear on the valve. Discharge line pulsation dampeners offer the further advantage of
limiting the flow and pressure variations characteristic of this kind of pump. Installing a properly sized pulsation dampener will improve
pump performance and may reduce system costs dramatically by permitting the substitution of smaller piping.
Safety Valves
Motor-driven positive displacement pumps can develop excessive discharge pressures long before thermal overload devices interrupt
the motor electrical circuit. To prevent a blocked discharge line from causing damage to the pump, piping, or process equipment, install
an LMI Safety Valve in the pump discharge line. This valve is designed and sized to handle system flow rates and pressures safely while
resisting corrosion by the process liquid.
Install the safety valve in the discharge line between the pump and the nearest shut-off valve (this will prevent pump damage from
accidental valve closure). Pipe the safety valve outlet back to the suction tank or to drain, but in either case ensure that the pipe end
is continuously visible so safety valve leakage may be detected. LMI safety valves must be installed at top of supply tank in order to
function properly (see Figure 5).
Che k Valves
A check valve should be installed at the point where the discharge line enters a boiler or other high-pressure vessel. This will prevent
back flow through the discharge piping and will isolate the pump discharge from system pressures (a safety consideration).
Shut-off Valves
Provide shut-off valves in both suction and discharge lines next to the pump. Locate discharge line shut-off valve downstream from
the inlet connection of the safety valve. Figure 5 shows recommended valve locations.
Figure 6: Suction Lift Installation

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2.7 Leak Detection
Series G, Model B pumps are equipped with a leak detection port. For ease of installation, each pump has a plastic tubing connector
installed in the leak detection port (see item 448 in Figure 8). In the event of a failure of the oil seal (7 in Figure 7) or diaphragm assembly
(261 in Figure 8), pump drive oil or process fluid will escape from this leakage port. During pump installation, actions should be taken
to ensure that this leakage is safely collected by installing tubing between the leak detection port and an appropriate containment vessel.
2.8 Electrical Connections
Ensure that the electrical supply matches the pump motor dataplate characteristics.
Before operating the pump, check the direction of rotation of the motor to be sure it matches the direction of the arrow stamped on the
motor (rotation should be clockwise when viewed from the top of the motor). If motor rotation is incorrect, refer to the motor data plate
or motor manufacturer’s instructions for reversing.
Operation with the wrong motor rotation will damage the pump and motor and void the warranty.
Do not forget to connect the pump to an earth ground!
Electric protection of the motor (fuses, overload meters or relays) should correspond to the rated current indicated on the motor data
plate.
3.0 Operation
3.1 Initial Start-Up
Check that all mounting bolts are tight, piping is installed properly, and the discharge line is open.
Check oil drain plug for tightness. Remove the oil fill cap and fill the pump casing until level is between the markings on the oil fill
cap dipstick, (approximately 3 quarts [2.8 Liters]).
The oil furnished with the pump is grade AGMA No. 5 EP with a viscosity of 1000 SSU at 100° F (218.4 cSt
at 40° C). For operation in ambient temperatures below 50° F (10° C), substitute AGMA No. 2 EP with a
viscosity of 400 SSU at 100° F (86.4 cSt at 40° C). Manufacturers' equivalent oils are shown below.
ABOVE 50° F (10° C) BELOW 50° F (10° C)
Chevron N.L. Gear Compound 220 Chevron N.L. Gear Compound 68
Exxon Spartan E.P. 220 Exxon Spartan E.P. 68
Mobil Mobilgear 630 Mobil Mobilgear 626
Texaco Meropa 220 Texaco Meropa 68
Shell Omaha 220 Shell Omaha 68
CAUTION
!
CAUTION
!

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Before switching on power to the pump, turn the capacity adjustment knob to zero. Check that all shut-off
valves in the suction and discharge lines are open before increasing the capacity adjustment from zero.
Manual Capa ity Control
To adjust pump capacity, loosen the stroke locking screw located in the pump side cover. Pump capacity is adjusted by turning the
micrometer type stroke adjustment knob clockwise to decrease capacity or counterclockwise to increase capacity as required. The
adjustment scale is marked in percent (%) of full stroke, with calibration lines on the knob at 1% intervals. After adjusting the knob
to the desired capacity setting, hand tighten the stroke locking screw to maintain the capacity setting.
Filling Pumping System
It is especially important that pump suction and discharge lines be free of entrained air. To ensure this condition, operate the pump
without any discharge pressure and fill the entire pumping system with liquid before starting pressure tests. A simple method to assure
priming of the pump is to install a tee and a shut-off valve at the discharge connection of the pump.
If the pump is idle for long periods, temperature changes in the process liquid may produce air in the system. To discharge the air, install
a valve in the discharge line which will allow the process liquid to be pumped to exhaust when starting the pump.
Capa ity Calibration
After the first 12 hours of operation, the pump may be tested and calibrated to find the exact pump capacity under specific operating
conditions.
Usually, calibrating the pump at only 1 , 5 , and 1 percent capacity settings is enough to indicate pump performance throughout the
adjustment range.
The pump can be calibrated by measuring the decrease in liquid level pumped from a calibrated vessel. This method is recommended
for hazardous liquids because it eliminates operator contact with the liquid. LMI test-tube Calibration Columns are available for
convenient and accurate calibration of any pump.
The pump can also be calibrated by collecting and measuring pumped liquid at the pump discharge port. It may be necessary to create
discharge head at the liquid take-off point so that the pump will operate properly (see Section 2.6 for recommended ways to do this).
This method is not generally recommended as it may e pose operating personnel to hazardous liquids.
Furthermore, the pump may over pump dramatically and the position of the capacity adjustment knob may
have little effect on measuring flow rate.
4.0 Maintenance
4.1 Spare Parts
The following spare parts should be stocked for each pump to prevent serious delays in repairs. Refer to Figures 7–14 and to the
accompanying parts lists.
B4 Metallic Liquid End
(1) Diaphragm Assembly (261)
(1) Oil Seal (7 )
(2) Check Valve Assemblies (425)
(See parts list )
All Other Liquid Ends
(1) Diaphragm Assembly (261)
(1) Oil Seal (7 )
(2) Seat, O-Ring, Ball Set (423)
(See parts list )
CAUTION
!
CAUTION
!

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Parts orders must include the following:
1. Quantity required
2. Part number
3. Part description
4. Pump serial number (found on dataplate)
5. Pump model number (found on dataplate)
6. Pump product code (found on dataplate)
Always include the serial number, model number, and product code in all correspondence regarding the unit.
4.2 Shipping Pumps for Repair
Pumps can not be accepted for repair without a Return Material Authorization. Pumps should be clearly labeled to indicate the liquid
being pumped. Process liquid should be flushed from the pump liquid end and oil should be drained from the pump housing before the
pump is shipped.
Federal law prohibits handling of equipment that is not accompanied by an OSHA Material Safety Data Sheet
(MSDS). A completed MSDS must be packed in the shipping crate with any pump shipped for repair. These
safety precautions will aid the troubleshooting and repair procedure and preclude serious injury to repair
personnel from hazardous residue in pump liquid end. A Materials Safety Data Sheet must accompany all
returns.
All inquiries or parts orders should be addressed to your local LMI Master Distributor.
4.3 Preventive Maintenance
LMI pumps are carefully designed, manufactured, assembled, and quality tested to give reliable service with minimal maintenance.
However, a weekly maintenance check is recommended to visually confirm proper operation of the pump.
Drive
Initially, change gear drive oil after the first 25 hours of operation. Then change drive oil after every 4 hours of operation or every
six months, whichever comes first.
Diaphragm Assembly
The Series G diaphragm assembly should be replaced every 4 hours of operation to avoid the possibility of failure. Refer to the
instructions in the “Corrective Maintenance” section.
Oil Seal
The Series G oil seal should be replaced every 4 hours of operation to avoid the possibility of failure. Oil seal replacement requires
the removal of the diaphragm assembly, so it is recommended that the oil seal and diaphragm assembly be replaced at the same time.
Refer to the instructions in the “Corrective Maintenance” section.
Che k Valves
LMI recommends that check valve balls, seats, gaskets, and O-Rings be replaced on an annual basis. If highly corrosive material (acids,
slurries, etc.) is being pumped, some applications may require more frequent replacement.
To determine if check valves need maintenance, disassemble the check valves following the instructions in the “Corrective
Maintenance” section. Inspect the ball check and seat for chemical or physical damage. The ball should be perfectly round and free
of pits, mars, or scratches. The seat should retain a sharp edge where the ball contacts for proper sealing. If the seat edge is worn or
damaged, or has any pits, mars, or scratches, it should be replaced. If the ball and/or seat is excessively damaged, the replacement
schedule should be shortened accordingly. If the ball and seat are both in good condition, the replacement schedule can be lengthened.
Complete instructions for replacing worn check valve parts are given in the “Corrective Maintenance” section.

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4.4 Corrective Maintenance
Before carrying out any servicing operation on the metering unit or pipes, disconnect electrical power from
the pump, and take the necessary steps to ensure that the harmful liquid they contain cannot escape or come
into contact with personnel. Suitable protective equipment must be provided. Check that there is no pressure
before proceeding with dismantling.
Cleaning Fouled Che k Valves
Check valve assemblies are designed to be self cleaning and should seldom need servicing. Fouled check valves can usually be cleaned
by pumping a solution of mild detergent and warm water (if compatible with liquid being pumped) for 15 minutes, followed by flushing
with water.
Che k Valve Repla ement
Before beginning work on the valve assemblies, make sure the shut-off valves are closed and that pressure has been bled from the system.
When replacing the valves, take care to systematically change their O-Rings and/or gaskets. Take care to properly assemble the valve
assemblies; the ball must be placed on the sharp edge of the seat.
Check valves are supplied in two different configurations: plastic, and stainless steel. Be sure to refer to the appropriate instructional
set below.
Be sure to follow instructions carefully and refer to the appropriate Figure when reassembling check valves.
If check valve cartridges are installed incorrectly, one of the following will occur: (a) immediate severe
damage to pump mechanism, (b) no pumping, (c) reverse pumping action (from discharge line into suction
line).
Plasti Che k Valves
Disassembly (Refer to Figure 9 or 11)
1. Unscrew the union nut (435). The union end (445) is held in place by the union nut and will separate easily from the other liquid
end parts.
2. Unscrew the ball guide (424) from the liquid end.
3. Screw the union nut part way (one or two turns) onto the end of the ball guide that has the seat in it. Be sure the union nut is on
loosely. This will allow a gap for the seat (42 ) to fall into as it is removed from the ball guide.
4. Sit the ball guide/union nut onto a flat surface with the union nut down. Looking into the top of the ball guide, you will see four
large holes surrounding one small hole. Insert a thin, blunt instrument such as a hex head screwdriver into the small center hole
until it rests on the top of the ball (422).
5. Tap screwdriver gently with a hammer until the ball and seat are released from the ball guide.
If you are disassembling unit for inspection only, be sure to use a blunt instrument and tap gently to avoid
damaging the ball. If the ball and/or seat are damaged during disassembly, they will have to be replaced. If
available, to avoid damage, it is advisable to use gentle air pressure (applied at end opposite the seat - 420)
for ball and seat removal.
6. Carefully remove the two or three O-Rings (depending on liquid end style) from the ball guide and seat.
7. Carefully clean any parts to be reused. If any chemicals are used in the cleaning process, ensure that they are compatible with the
process liquid.
CAUTION
!
CAUTION
!
CAUTION
!

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Plasti Che k Valves:
Reassembly
1. Fit new O-Rings into position on the ball guide and seat.
To assure a tight, leak free seal, new O-Rings should be used each time the check valves are disassembled.
2. Drop the ball into the curved inner chamber end of the ball guide.
3. Sit the ball guide on a flat surface so that the side with the ball faces upwards. Position seat on the ball guide, trapping the ball inside.
When the seat is pressed into the ball guide, the beveled edge of the seat must be facing outward. The bevel should not face the
inside of the check valve (refer to Figure 9 or 11). Use a flat surface such as a board to press the seat into the ball guide with firm,
even pressure.
If the seat is improperly positioned, the ball will not create a tight seal and poor pumping performance will
result.
4. Position the union end (445) onto the correct end of the ball guide. Refer to Figure 9 or 11, as the correct end is determined by
whether the valve is intended for the suction or discharge port of the liquid end. Slip the union nut (435) over the union end and
screw tightly (hand tight only) onto the ball guide.
The order of assembly of the suction and discharge check valves is different. Refer to Figure 9 or 11 for proper
assembly order. If check valve cartridges are installed incorrectly, one of the following will occur: (a)
immediate severe damage to pump mechanism, (b) no pumping, (c) reverse pumping action (from discharge
line into suction line).
5. Screw the valve assembly into the liquid end body (hand tight only). DO NOT OVER TIGHTEN.
B60 & B80 Liquid End Stainless Steel Che k Valves
Disassembly (Refer to Figure 12)
1. Unscrew the three screws (441 & 442) and remove them and their three washers (439).
2. Remove the valve clamp (437).
3. The connection (435), seat (42 ), ball (422) and ball guide (424) should all now slip apart easily.
4. Remove and discard the three gaskets (419).
5. Carefully clean any parts to be reused. If any chemicals are used in the cleaning process, ensure that they are compatible with the
process liquid.
B60 & B80 Liquid End Stainless Steel Che k Valves
Reassembly
1. Drop the ball into the curved inner chamber end of the ball guide.
2. Place a new gasket on the rim of the ball guide, and sit the seat on top of the ball guide, trapping the ball and gasket between the
seat and ball guide.
Do not reuse old gaskets (419). Even if ball and seat are not worn and do not need replacing, new gaskets
must be used any time the check valves are disassembled.
3. Position the connection (435) onto the correct end of the ball guide with a gasket trapped between the two metal surfaces. Refer
to Figure 12, as the correct end is determined by whether the valve is intended for the suction or discharge port of the liquid end.
The order of assembly of the suction and discharge check valves is different. Refer to Figure 12 for proper
assembly order. If check valve cartridges are installed incorrectly, one of the following will occur: (a)
immediate severe damage to pump mechanism, (b) no pumping, (c) reverse pumping action (from discharge
line into suction line).
CAUTION
!
CAUTION
!
CAUTION
!
CAUTION
!

14
4. Position the check valve assembly onto the liquid end, trapping a gasket between the two metal surfaces. (Seat and pump head).
5. Slide the valve clamp (437) over the connection (435) and screw into the liquid end using the three screws (441,442) and their
split washers (439). Since one screw (441) is shorter than the others, be sure that it is screwed into the appropriate hole.
B40 Liquid End Stainless Steel Che k Valves:
Disassembly (Refer to Figure 1 )
B4 stainless steel check valves differ from the plastic versions in that the ball seat is integral to the ball guide. The seats cannot easily
be inspected for damage or wear. If you suspect that the check valve may be damaged or worn, replace the entire check valve assembly
as per the instructions below.
1. Unscrew the coupling (445).
2. Unscrew the ball guide (424) from the liquid end.
3. Remove and discard the O-Rings (419).
4. Carefully clean any parts to be reused. If any chemicals are used in the cleaning process, ensure that they are compatible with
the process liquid.
B40 Liquid End Stainless Steel Che k Valves:
Reassembly
1. Screw the correct end of the check valve assembly into the liquid end (refer to Figure 1 ), trapping a new O-Ring between the
liquid end and the check valve assembly.
To assure a tight, leak free seal, new O-Rings should be used each time the check valves are disassembled.
The order of assembly of the suction and discharge check valves is different. Refer to Figure 10 for proper
assembly order. If check valve cartridges are installed incorrectly, one of the following will occur: (a)
immediate severe damage to pump mechanism, (b) no pumping, (c) reverse pumping action (from discharge
line into suction line).
2. Screw the coupling (445) onto the check valve assembly, trapping a new O-ring (419, 423) between the coupling and the check
valve assembly.
Diaphragm Assembly Repla ement
It is recommended that the oil seal and diaphragm assembly be replaced at the same time. The instructions given under “Replacing the
Oil Seal” are complete instructions for replacing both the oil seal and the diaphragm assembly. If you plan to replace both, refer to the
“Replacing the Oil Seal” instructions, and disregard the instructions below. These instructions are intended for use only if the diaphragm
assembly is being replaced independent of the oil seal.
Before beginning diaphragm replacement, make sure that all shut-off valves are closed and all pressure is bled from the liquid end.
Disassembly (Refer to Figures 7 and 8)
1. Set the stroke adjusting knob to 1 %.
2. Disconnect the suction and discharge piping.
3. Unscrew the six diaphragm head bolts.
4. Remove the diaphragm head assembly from the pump body.
5. Turn the motor fan by hand (remove the motor shroud if necessary) until the end of the diaphragm assembly (261) is fully forward,
and unscrew the diaphragm assembly from the connecting rod (6 ).
CAUTION
!

15
Reassembly (Refer to Figures 7 and 8)
1. With the stroke adjusting knob at 1 % and the diaphragm fully forward as in steps 1 and 5 above, screw the diaphragm assembly
into the connecting rod until it reaches its natural mechanical stop.
2. Turn the motor fan by hand until the diaphragm rests properly on the diaphragm support (23 ). Reinstall the motor shroud if
previously removed.
3. Fit the diaphragm head back into place on the pump body.
4. Torque the six diaphragm head bolts to 9 in-lb (1 Nm) in a crisscross pattern.
Repla ing the Oil Seal
Before beginning oil seal replacement, make sure all shut-off valves are closed and all pressure has been bled from liquid end.
When replacing the oil seal, the diaphragm assembly must be removed first. For ease of service, it is recommended that the oil seal be
replaced in conjunction with the diaphragm assembly. Therefore, the instructions below include the “Diaphragm Assembly
Replacement” instructions, and can be used for both oil seal replacement and diaphragm assembly replacement.
Disassembly
Steps 2–6 below correspond to the five “Diaphragm Replacement — Disassembly” steps. (Refer to Figures 7 and 8).
1. Drain oil from the pump by unscrewing the drain plug (2 ) and O-Ring (19).
2. Set the stroke adjusting knob to 1 %.
3. Disconnect the suction and discharge piping.
4. Unscrew the six diaphragm head bolts.
5. Remove the diaphragm head assembly from the pump body.
6. Turn the motor fan by hand (remove the shroud if necessary) until the end of the diaphragm assembly (261) is fully forward, and
unscrew the diaphragm from the connecting rod (6 ).
7. Remove the diaphragm support ring (23 ).
8. Remove the retaining ring (22 ) from the connecting rod.
9. Slide the small oil seal clamp (21 ) off the connecting rod.
1 . Remove the large oil seal clamp (8 ) by unscrewing the four slotted screws (9 ).
11. Pull the oil seal (7 ) off of the connecting rod.
Reassembly
Steps 5–8 below correspond to the four “Diaphragm Replacement — Disassembly” steps. (Refer to Figures 7, 8, and 13).
1. Install a new oil seal (7 ) onto the connecting rod.
2. Slide small oil seal clamp (21 ) onto the end of the connecting rod and secure in place with the retaining ring (22 ). A drive socket
large enough to fit over the end of the connecting rod should be used to push the retaining ring until it snaps into place in the retaining
ring groove in the connecting rod.
3. Secure the large oil seal clamp (8 ) over the oil seal with the four slotted screws (9 ).
4. Place the diaphragm support ring (23 ) into position making sure beveled side (for diaphragm support) is facing up (refer to Figure
8 if necessary). For B8 liquid ends, the support ring (23 ) has stepped diameters. Make sure that the larger diameter is installed
into the metal adapter ring (225 in Figure 13).
5. With the stroke adjusting knob at 1 % and the diaphragm fully forward as in steps 2 and 6 of disassembly instructions, screw the
diaphragm assembly into the connecting rod until it reaches its natural mechanical stop.
6. Turn the motor fan by hand until the diaphragm rests properly on the diaphragm support ring (23 ). Reinstall the motor shroud
if previously removed.
7. Fit the diaphragm head back into place on the pump body.
8. Torque the six diaphragm head bolts to 9 in-lb (1 Nm) in a crisscross pattern.
9. Add oil to pump, following directions given in “Initial Start-up” in Section 3.

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5.0 Troubleshooting Guide
5.1 Symptoms & Remedies
Pump will not operate ...........................• Low process liquid level in the tank. Add liquid.
• Worn or dirty check valves. Clean or replace.
• Blocked discharge line. Clear line.
• Frozen liquid. Thaw liquid throughout pumping system.
• Blown fuse. Replace fuse.
• Open thermal overload device in motor starter. Reset device.
• Broken wire. Locate and repair.
• Low voltage. Investigate and correct (wiring may be too light).
• Pump not primed. Allow suction line and pump head to fill with
liquid before pumping against pressure. Refer to “Filling Pumping
System” in Section 3.
• Capacity adjustment set at zero. Readjust capacity.
Insufficient delivery ...............................• Incorrect capacity adjustment. Readjust capacity setting.
• Incorrect pump speed. Match line voltage and frequency to pump
motor data plate.
• Starved suction. Increase piping size or suction head.
• Leaky suction piping. Repair piping.
• High suction lift. Rearrange equipment to decrease lift.
• Liquid near boiling. Cool liquid or increase suction head.
• Leaky safety valve in discharge line. Repair or replace safety valve.
• High liquid viscosity. Reduce viscosity (e.g., heat or dilute liquid).
• Worn or dirty check valve seats. Clean or replace.
Erratic delivery ......................................• Leaky suction piping. Repair piping.
• Leaky safety valve. Repair or replace safety valve.
• Insufficient suction head. Raise suction tank level or pressurize tank.
• Liquid near boiling. Cool liquid or increase suction head.
• Worn or dirty check valves. Clean or replace.
• Clogged or dirty line strainer. Clean strainer.

17
Motor and pump body hot.....................• Normal operating temperature of both motor and pump body is
frequently uncomfortable to the touch. However, neither should
exceed 2 ° F (93° C).
• Power supply does not match electrical requirement of motor. Insure
proper matching of power supply and motor.
• Pump is being operated at greater than rated performance. Reduce
pressure or stroke speed. If this is not practical, contact service
facility.
• Pump improperly lubricated. Drain oil and refill with proper amount
of recommended lubricant.
Pump still pumps even at
zero capacity setting...............................• Misadjusted micrometer knob. Readjust capacity setting.
• Insufficient discharge pressure. Correct condition (e.g., install a
back pressure valve).
Gear noise............................................... • Excessive backlash. Consult service facility.
• Worn bearings. Consult service facility.
• Wrong or insufficient lubricant. Replace or replenish lubricant.
Loud knock with each stroke ................• Excessive gear set wear. Consult service facility.
• Worn bearings. Consult service facility.
Noisy operation in liquid end................• Noise in check valves. Ball checks move up and down with some
force. A distinct “clicking” noise is normal, especially in metal
piping systems.

18
6.0 Parts
Basic Parts
Figure 7: Series G Basic Parts — Side View
410
400
370
60
80 90 70
280
460
470
450
465
340
343
344
360
377
410
376
400
390
56C Motor
IEC 80
Motor
Check valves
Refer to Fig res 9-12
40

19
Figure 8: Series G Basic Parts — Top View
Basic Parts

2
Figure 9: B40 Plastic Check Valve Parts Figure 10: B40 Metallic Check Valve Parts
Figure 11: B60 & B80 Plastic Check Valve Parts Figure 12: B60 & B80 Metallic Check Valve Parts
Check Valve Parts