Available in demand or bypass mode, these Delavan FB3 Diaphragm Pumps with QA Ports are reliable 12V sprayer pumps used for low pressure spraying and fluid transfer applications.

Delavan PowerFlo 12V FatBoy Series 3 Diaphragm Pump with QA Ports

Delavan FatBoy Demand QA Pump
USD $247.66
  • SKU: 7971-101E
Delavan FatBoy Bypass QA Pump
USD $240.75
  • SKU: 7971-111E
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Available in demand or bypass mode, these Delavan FB3 Diaphragm Pumps with QA Ports are reliable 12V sprayer pumps used for low pressure spraying and fluid transfer applications.

Product Description

With a new and improved design that extends pump life and improves performance, the Delavan PowerFlo FB 3 Series Diaphragm Pumps with Quick Attach Ports are here to deliver reliability and optimal performance in many of your professional spraying applications.

The improved pump design results in extended pump life and a much more efficient operation over a wide pressure range compared to similar 7 gpm diaphragm pumps. This gives the consumer a reliable sprayer pump that generates less amp draw and less heat, resulting in superior performance in the long run. Also, a new diaphragm retaining system allows for the pump to maintain its flow for longer hours of operation in demanding applications.

Available in either demand or bypass mode, these Delavan 7971 PowerFlo 12V Diaphragm Pumps meet the needs of professionals in the lawn / turf, roof cleaning, fluid transfer, and dust suppression markets.

Two models to choose from:

  • Delavan 7971-101E - Demand Pump with QA Ports
  • Delavan 7971-111E - Bypass Pump with QA Ports

Both of these Delavan FB3 Series Pumps with QA Ports are powered by durable 12V DC electric motors, delivering reliable performance in agricultural spraying, lawn spraying, and fluid transfer applications. Viton valves and a Santoprene diaphragm provide excellent chemical resistance when working with common agricultural chemicals, such as liquid fertilizers, herbicides, pesticides, insecticides, and other hard-to-handle fluids. These pumps are also ideal for roof cleaning with mild chemicals, dust suppression, and much more.

Demand Pumps have a pressure sensing switch that eliminates the need for a pressure regulator. They are used in applications that require a set flow and pressure (eg. spray wands on spot sprayers). If a faucet or valve is opened down stream of the pump, line pressure drops, making the pump start automatically. When the valve shuts, line pressure increases, making the pump shut off automatically. The switch reacts to outlet pressure and interrupts power at a preset shutoff pressure. If outlet pressure drops below a predetermined level, the switch closes and the pump only operates until shutoff pressure is achieved once again.

Bypass Pumps are common in applications where a wide range of flows and pressures are required and when frequent stopping and starting of the motor is required (eg. a spray bar with multiple nozzles, each controlled separately). The pump continues to run regardless of pressure in the system. For the spray bar example, the flow rate is different when one nozzle is turned on as opposed to having two or more nozzles turned on. As nozzles are turned off, excess flow is bypassed within the pump. Bypass pumps are useful in applications where automatic demand switches aren't required.

We recommend using the TeeJet AA122 Series Poly Line Strainer (see Related Products) to help eliminate contaminates from running through your bypass or demand pump. Also, bypass pumps require the use of a pressure regulator, so it is recommended to use the TeeJet 6815 Brass Regulator (see Related Products).


  • Max. Flow: 7.0 gpm
  • Max. Pressure: 60 psi
  • Max. Draw: 35 Amps
  • Max. Fluid Temperature: 140° F
  • Voltage: 12 VDC, permanent magnet, totally enclosed, non-ventilated type
  • Port Sizes: 3/4" Quick Attach inlet and outlet
  • Delavan 7971-101E has a 60 psi demand switch that only operates when liquid flow is required
  • 5 chamber positive displacement pump
  • Polypropylene housing
  • Viton valves
  • Santoprene diaphragm
  • Stainless steel fasteners
  • Self-priming up to 14'
  • Can be run dry
  • Weight: 8 lb

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