AMT Replacement Diaphragms for Diaphragm Pumps

How AMT Diaphragm Pumps Work

Understanding the role of the diaphragm helps explain why selecting the correct AMT replacement diaphragm and material is important for pump performance and service life.

AMT diaphragm pumps in this category use a diaphragm to create the suction and discharge strokes inside the pump body. As the diaphragm moves through its cycle, fluid is drawn into the pump and discharged through the outlet while the diaphragm separates the fluid side of the pump from the drive mechanism.

The drive mechanism uses a gearbox and plunger assembly to move the diaphragm through its stroke. A neoprene check valve assembly controls the direction of fluid flow through the pump.

Because the diaphragm is a primary wear component, the correct AMT part number and material should be selected according to the pump model and the fluid being handled.

AMT 2 Inch Replacement Diaphragms

AMT 2 Inch Pump Models

The following AMT 2 inch diaphragm pump models use replacement diaphragm part number 3380-300-00. Confirm the complete pump model before ordering.

AMT 2 Inch Diaphragm Part Number

Replacement diaphragm part number: 3380-300-00

This part number identifies the replacement diaphragm used for the AMT 2 inch pump models listed above. Material options may vary by availability and application. Contact Ken’s Distributing with your AMT model and fluid application if you need help selecting the appropriate diaphragm material.

AMT 2 Inch Diaphragm Materials

Rubber: A cost-effective option for AMT pumps handling clean water, groundwater, and lightly sediment-laden water where oil, fuel, and aggressive chemical exposure are not present.

Neoprene: Commonly selected for construction dewatering, dirty water, groundwater, slurry, and outdoor pumping applications where flexibility and weather resistance are important.

Buna/Nitrile: Commonly used when an AMT pump handles oily wastewater, fuel-contaminated groundwater, lubricants, or other petroleum-containing fluids.

TPE: A durable option for high-cycle, continuous-duty, and selected demanding pumping applications where fatigue resistance and longer service intervals are priorities.

AMT 2 Inch Check Valve Assembly

Neoprene check valve assembly part number: 3360-070-90

The check valve assembly controls one-way fluid movement through the pump. Inspect the check valve whenever the diaphragm is serviced. Worn, damaged, or debris-fouled check valves can reduce pump performance and make priming more difficult.

If flow remains erratic or the pump does not hold prime after diaphragm service, inspect the check valve assembly and surrounding components according to AMT service procedures.

Common Applications for AMT 2 Inch Diaphragm Pumps

• Construction site dewatering
• Trench and pit pumping
• Foundation and excavation water removal
• Groundwater control
• Irrigation water transfer
• General industrial fluid transfer

AMT 3 Inch Replacement Diaphragms

AMT 3 Inch Pump Models

The following AMT 3 inch diaphragm pump models use replacement diaphragm part number 3370-300-00. Confirm the complete pump model before ordering.

AMT 3 Inch Diaphragm Part Number

Replacement diaphragm part number: 3370-300-00

This part number identifies the replacement diaphragm used for the AMT 3 inch pump models listed above. Contact Ken’s Distributing to confirm current material availability for your AMT model and application.

AMT 3 Inch Diaphragm Materials

Rubber: A practical option for AMT 3 inch pumps handling clean water, groundwater, and lightly sediment-laden water in standard construction and dewatering applications.

Neoprene: Commonly selected for construction dewatering, slurry, outdoor operation, and other applications where greater resistance to weathering and physical wear is useful.

Buna/Nitrile: Designed for applications involving oily water, petroleum contamination, fuels, lubricants, and related hydrocarbon-containing fluids.

TPE: A durable material option for selected continuous-duty, high-cycle, abrasive, or demanding AMT pump applications.

AMT 3 Inch Check Valve Assembly

Neoprene check valve assembly part number: 3354-070-90

Inspect the check valve assembly during diaphragm service, especially if the pump has accumulated significant operating hours or has experienced erratic flow, difficult priming, or reduced performance.

Replace worn or damaged check valve components according to the service requirements for your AMT pump model.

Common Applications for AMT 3 Inch Diaphragm Pumps

• Construction dewatering
• Municipal stormwater control
• Utility and bypass pumping
• Industrial slurry and wastewater transfer
• Higher-volume trench and excavation dewatering
• Groundwater removal

How to Choose an AMT Diaphragm Material

The fluid being pumped and the operating environment are important factors when selecting an AMT replacement diaphragm material.

Clean water, groundwater, and light sediment: Rubber or neoprene may be appropriate. Rubber is a cost-effective option for standard clean-water applications, while neoprene provides additional weather and physical durability for many construction environments.

Construction slurry and outdoor dewatering: Neoprene is commonly selected for applications involving sediment, dirty water, construction wastewater, and outdoor pump operation.

Oily wastewater and petroleum-contaminated fluids: Buna/nitrile is commonly selected where greater resistance to oils, fuels, and hydrocarbons is required.

Continuous-duty and demanding operation: TPE may be appropriate for selected high-cycle applications where fatigue resistance and longer service intervals are important.

If your fluid or operating conditions fall outside these general categories, contact Ken’s Distributing with your AMT pump model and application details before ordering.

How to Identify the Correct AMT Replacement Diaphragm

Start with the complete AMT model number shown on the pump identification tag. The 2 inch and 3 inch AMT pump families use different diaphragm part numbers, so nominal pump size and model information should be confirmed before ordering.

Useful information includes:

• AMT pump model number
• Nominal pump size
• Existing diaphragm part number, if available
• Current diaphragm material
• Fluid being pumped
• Operating environment

If the identification tag cannot be read, photographs of the pump, engine or motor arrangement, existing diaphragm, and any visible part numbers may help Ken’s Distributing identify the correct AMT replacement part.

Signs Your AMT Diaphragm May Need Replacement

AMT diaphragm wear may appear as gradual performance loss before a complete diaphragm failure occurs. Regular inspection can help identify deterioration early and reduce the risk of additional pump repairs.

Inspect the diaphragm if you notice any of the following:

• The pump takes noticeably longer to prime
• Discharge flow decreases under otherwise normal operating conditions
• Air appears in the discharge stream
• Pump cycling becomes irregular or labored
• Visible cracking, stiffening, surface damage, or deformation appears on the diaphragm
• Fluid appears where it should not be within the pump assembly
• Pump vibration changes noticeably during normal operation

A damaged diaphragm should be serviced promptly. Continued operation with a failed diaphragm may allow fluid or debris to reach other pump components and increase the cost of repairs.

AMT Diaphragm Installation and Maintenance

Installation

Confirm the AMT pump model, replacement diaphragm part number, and selected material before installation.

• Clean the diaphragm housing and mounting surfaces before installing the new diaphragm.
• Confirm the replacement diaphragm dimensions and mounting arrangement against the original AMT part.
• Tighten cover plate hardware evenly according to the recommended AMT service procedure.
• Inspect the check valve assembly while the pump is disassembled.
• Inspect surrounding wear components for damage, corrosion, or debris before reassembly.

Maintenance

• Inspect AMT diaphragms regularly according to operating hours and application conditions.
• Increase inspection frequency for pumps handling abrasive slurry or operating continuously.
• Flush the pump after handling sediment-laden, oily, or chemically active fluids.
• Inspect check valves and other wear components whenever diaphragm service is performed.
• Store the pump according to AMT recommendations when it will be out of service for an extended period.

Bulk Pricing for AMT Replacement Diaphragms

Contractors, distributors, rental companies, and businesses maintaining multiple AMT diaphragm pumps can qualify for bulk pricing on larger diaphragm orders.

Ken’s Distributing also offers blanket order programs for organizations that need a recurring supply of AMT replacement diaphragms and related pump parts.

Contact Ken’s Distributing with your AMT pump model, diaphragm part number or size, required material, and estimated annual quantity for pricing information.

Learn More About Blanket Orders

Browse Other Diaphragm Pump Brand Categories

Ken’s Distributing also supplies replacement diaphragms and pump parts for additional diaphragm pump manufacturers. Use the appropriate manufacturer page when servicing a pump from another brand.

• CH&E Replacement Diaphragms
• Magnum Replacement Diaphragms
• Mud Hog Replacement Diaphragms
• Wacker Replacement Diaphragms
• Gorman-Rupp Replacement Diaphragms
• Multiquip Replacement Diaphragms
• Riverside Replacement Diaphragms
• Tsurumi Replacement Diaphragms

Shop Replacement Diaphragms by Material

• Rubber Replacement Diaphragms
• Neoprene Replacement Diaphragms
• Buna/Nitrile Replacement Diaphragms
• TPE Santoprene Replacement Diaphragms

Frequently Asked Questions About AMT Replacement Diaphragms

How do I find the correct AMT diaphragm for my pump?

Locate the AMT model number on the pump identification tag and compare it with the model tables above. The listed 2 inch AMT models use diaphragm part number 3380-300-00, while the listed 3 inch models use part number 3370-300-00. If your AMT model is not listed, contact Ken’s Distributing before ordering.

What diaphragm material should I use in my AMT pump?

The appropriate material depends on the fluid and operating conditions. Rubber and neoprene are commonly used for clean water and general construction dewatering, Buna/nitrile for applications involving petroleum contamination, and TPE for selected high-cycle or demanding applications. Contact Ken’s Distributing if you are unsure which material is appropriate.

Do AMT 2 inch and 3 inch pumps use the same diaphragm?

No. The AMT 2 inch pump models listed above use part number 3380-300-00, while the listed 3 inch models use part number 3370-300-00. Confirm the AMT pump model and correct part number before ordering.

Should I inspect the AMT check valve when replacing the diaphragm?

Yes. Inspect the check valve assembly whenever diaphragm service is performed. A worn, damaged, or debris-fouled check valve can contribute to poor flow, difficult priming, and reduced pump performance.

Can I change the diaphragm material in my AMT pump?

The diaphragm material should be selected according to the requirements of the specific AMT pump and application. Do not choose a different material based only on diaphragm dimensions. Confirm the AMT model, replacement part specifications, fluid type, and operating conditions before ordering. Ken’s Distributing can help determine the appropriate material for your pump.

What are the AMT 2 inch and 3 inch check valve part numbers?

The neoprene check valve assembly listed for the AMT 2 inch pump series is 3360-070-90. The neoprene check valve assembly listed for the AMT 3 inch pump series is 3354-070-90. Confirm your complete AMT pump model before ordering replacement components.

Is bulk pricing available for AMT replacement diaphragms?

Yes. Bulk pricing and blanket order programs are available for qualifying contractors, distributors, rental operations, and businesses maintaining multiple AMT pumps. Contact Ken’s Distributing with your AMT model, diaphragm requirements, and estimated quantity for pricing information.

Do you ship AMT replacement diaphragms to Canada?

Yes. Ken’s Distributing ships AMT replacement diaphragms throughout the United States and Canada. Contact Ken’s Distributing for shipping information on larger or recurring orders.