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This is a pressure-actuated unloader that is designed for any pump that fits within the flow and pressure range of the unloader. The unloader regulates the flow in the system and maintains system pressure via an adjustable nut that controls the amount of tension on a pressure spring. When no flow is going out the outlet port, all flow is diverted to the bypass port at virtually no pressure. The unloader is capable of handling one or more shut-off guns and should be run with no bypass (if the full flow from the pump is going through the unloader). It actuates at around 10% above the system pressure.

WARNING: This product might contain a chemical known to the State of California to cause cancer, and birth defects or other reproductive harm. For more information go to

Specification US Metric
Minimum Flow2.1 GPM7.9 L/min
Maximum Flow35.7 GPM135 L/min
Max Pressure1740 PSI120 bar
Continuous Temperature160 °F71 °C
Inlet Port3/4" BSP
Outlet Port3/4" BSP
Bypass Port3/4" BSP
Weight6.7 lbs.3 kg
The repair kits listed to the right are available for this pump. If you need further information about these repair kits, or have questions about other specific parts for your pump, please contact you local Giant distributor or contact Giant customer service.
Repair Kit – Part #09461-41
3 06735 O-Ring 1
6 07853-0001 O-Ring, Valve Stem 1
7 05898 Support Ring 1
9 05005-0010 Cup, 28MM 1
10 05015 Back Up Ring, 28MM 1
11 12207-0400 Ball 1
12 12216 Valve Spring 1
12A 12208-0100 Seat, Inlet 1
14 12244-0400 Valve Plate 1
14C 07035-0001 O-Ring 2
14D 06017-0100 Spring, Outlet Valve 1


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  • Giant Industries Limited Warranty
  • 22971C-51 Literature


Stainless Steel

Sample Pump

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