GRACO 571028 - Adjustable Return-to-Reservoir Pressure Relief Kit - 500-3500 PSI - 1/4” NPT

Adjustable Return-to-Reservoir Pressure Relief Kit designed to protect pumps and systems by automatically relieving excess pressure back to the reservoir. Provides adjustable pressure control from 500-3500 PSI with convenient 1/4" NPT inlet connection for easy installation and maintenance.

Specifications

• Thread: 1/4" NPT
• Max Working Pressure: 35-241 bar (500-3500 psi)
• Inlet Connection: 1/4" NPT
• Pressure Range: adjustable 500-3500 psi

Features

• Adjustable pressure relief from 500-3500 PSI
• Return-to-reservoir design for fluid conservation
• 1/4" NPT inlet for standard connections
• Kit includes all necessary components
• Pressure relief functionality
• Compatible with 24vdc motor systems

Applications

• Pump protection systems
• Hydraulic pressure control
• Lubrication systems
• Industrial fluid handling
• Progressive oil systems
• Progressive grease systems

Compatible Equipment

• G3 pumps
• Systems requiring 1/4" NPT connections
• G3GM Series pumps
• 96G005GM pump units
• Various GM gear pumps
• 24vdc motor systems

Related Parts

• 571071 - Adjustable Return-to-Reservoir Pressure Relief Kit (1/4" BSPP)
• 571058 - Pressure Relief-to-Atmosphere Kit (1/4" NPT)
• 571070 - Pressure Relief-to-Atmosphere Kit (1/4" BSPP), 56284BGM, 564138GM, 557819GM, Modu-FloGM, 563301GM, 96G005GM
• 563156 - VALVE, pressure relief, 750 psi (5.17 MPa, 51.71 bar)

Kit Contents

• 16C807 - VALVE, pressure relief, 500-3500 psi (3.44 MPa, 34.4 bar - 24.1 MPa, 241 bar), Set pressure 3000 psi ± 10% (20.69 MPa, 206.8 bar ± 10%)

Part of G3 Accessories line. BSPP version available as 571071. Atmosphere relief kits also available for applications not requiring return-to-reservoir function. Part 571028 is referenced multiple times as a pressure relief add-on component for various GM pump packages, but detailed specifications are not provided on this page. It appears to be an accessory item rather than a standalone product listing. Kit 571028 includes pressure relief valve 16C807. The valve can only be used on G3, G1, or G-Mini Pumps. Each pressure relief valve requires banjo kit p/n 571058 (except 16C807 because the banjo is already included in Kit 571028). The pressure adjustment screw may require periodic adjustments and turning it clockwise increases pressure.

Reference Manuals

• 340574 (Page 8) G3 Electric Lubrication Pump
• 340706 (Page 5) G3 Selection guide
• 352482 (Page 14) GM Powertrain Program Book
• 332291 (Page 35) G3 Standard Automatic Lubrication Pump
• 332298 (Page 47) G3 Pro Automatic Lubrication Pump;