FRD Variable Rate Pressure Limited Fuel Pumps
2.0-3.5 PSI and 4.0-7.0 PSI Models Up to 20 GPH Specified by Dickinson for Use With Their Diesel Stoves & Heaters
The FRD series fuel pumps are designed to supply fuel for low pressure, continuous operation applications such as heaters or stoves.
They incorporate a piston mechanism which, unlike a rubber diaphragm, can be used with all pump-grade gasoline, gasohol, diesel, and biodiesel fuels, and fuel blends.
FRD pumps self-regulate to a pre-set maximum pressure, pumping more or less fuel as the pressure in the output fuel line varies.
Variable frequency circuitry causes the FRD pumps to slow down and stop as the stove carburator, or day tank, fills and the pump reaches its pre-set pressure rating.
These pumps are ideal for applications where battery life, low noise, and best durability are important.
The lower pressure FRD-2-1 is the pump specified by Dickinson for use in their diesel stoves and heaters
IMPORTANT: Dickinson specifies that the FRD-2-1 pump must be installed within 12 inches of the level of the fuel metering valve ("carburetor") on a diesel heater or stove.
Unlike the older WEP pumps it replaces, it is a "pull" pump rather than a "push" pump.
If you are replacing an older pump, you may need to move the pump location so it is within 12 vertical inches of the metering valve
Pump cycles only when fuel is demanded
Continuous duty life (diesel fuel): >10,000 hours
Flow rates as high as 55 gph, but maximum outputs of 30 gph are more typical
Self-priming to at least 2 feet; maximum dry run time is 4 hours
Inlet (bottom)/Outlet (top): 1/8-27 NPSF (Dryseal American National Standard Straight Pipe Thread) will accept NPT tapered fittings without leaking, thread sealant recommended
No internal filter; a 70 micron or finer pre-filter is recommended
Average current draw is less than 2 amps at 12 volts
USCG 16623-1 and 16623-2 approved; ignition protected
Dichromate coating passes 96 hour salt spray test - not recommended for use where exposed to saltwater
Dimensions: 5.43"H x 2.76"Dia.
Note - a suffix number (typically -1 or -2) in part number refers to type of packaging
Made in USA
NOTE The FRD Series of pumps is supplied with a kit of commonly used installation fittings: mounting fasteners, wire terminals, hose barbs and clamps. Although the included instructions reference (4) hose clamps, they have been re-designed, and now only (2) are needed.
Heavy on the technical side...
Selecting among the Walbro FR Series electric fuel pumps:
All the FR electric pumps provide fuel until the fuel demand decreases, or flow is restricted - but they have different mechanisms for doing so.
FR pumps will cycle (pump) until they build up the pressure (head) in the outflow line - with an accompanying decrease in fuel flow - and reach their factory preset maximum pressure.
At this point, constant frequency pumps like the FRA will continue cycling - but no fuel will flow.
Variable frequency pumps, like the FRB and FRD, will slow and eventually stop cycling as the pressure builds.
If the pressure on the outflow side of the pump drops, both types of pump will start supplying fuel again.
Choosing an FR Series pump is often less dependent on the application, and more a matter of user preference:
FRA pumps are lower cost, basic models.
They have no built-in filter, and their constant cycling means electric current draw is constant - regardless of output, they are always making noise, they typically have a shorter lifespan (higher wear), and they can wear unevenly as the stroke can be shortened when operating near their maximal pressure.
FRB and FRD pumps have a more expensive variable frequency circuit board, always use their full stroke length - so wear is evenly distributed, do not always operate at full capacity/maximal cycling so less wear, longer life, less noise, and lower average current draw.
Additionally, the FRB models include a built-in/replaceable 70 micron mesh filter, so the user doesn't need to supply a pre-filter.
What the FR fuel pump is designed to do:
In carbureted applications - The FRA and FRB fuel pumps self-regulate to their maximum output pressure when the carburetor bowl is full, and respond to float movement in the carburetor as required.
When the engine demands more fuel, the pump increases its flow rate.
When the engine demand drops, the pump reduces its flow rate.
In diesel applications - The FRA and FRB pumps will deliver fuel to the diesel injector pump, assuring a positive pressure at the injector pump inlet.
These pumps are designed to refill diesel filters after service or replacement.
In transfer applications, including fuel polishing, FRA and FRB pumps run continuously, as long as electrical power is supplied to the pump, and output back pressure is low.
In diesel heater and stove applications, the task-specific FRD pumps will slow their cycling rate to deliver only the fuel required by the stove fuel metering valve ("carburetor").
FRD pumps can also fill day tanks in gravity feed installations.
Complete list of approved fuels for FR pumps:
Unleaded regular gasoline, premium gasoline, gasoline-alcohol blends, diesel fuel, bio-diesel, Stoddard solvent, E85.
The versatile FR pumps are capable of pumping fluids other than fuels - including water and oils, thus having potential uses in many diverse applications. Please consult with us first, however, if you have a non-listed application in mind for one of these pumps, as there may be technical issues to resolve.