031-0057 1/4" Unloader Valve Elbow For Sandborn SC23 SC46 EC5 Compressor Pump

Replacement For Sanborn 031-0057 Air Compressor Unloader Elbow Valve

1/4" Compression x 1/8"-27 straight thread – Aftermarket Direct Replacement

Restore proper compressor operation with this high-quality aftermarket replacement for Sanborn / Industrial Air part number 031-0057. This brass 90° unloader elbow is designed to replace the original valve and allows the compressor to unload head pressure when the compressor shuts off. By relieving this pressure, the motor can restart without having to overcome compressed air trapped in the pump discharge line.

This is an aftermarket direct replacement and is not manufactured by Sanborn.

Specifications

• Replaces OEM Part #: 031-0057
• Fitting Size: 1/4" Compression x 1/8"-27 straight thread (Note: 1/8"-27 straight thread measures about 3/8" in diameter for reference)
• Material: Brass
• 90° Elbow Design
• Internal Schrader-style unloading valve

Compatible With

Commonly used on many:

• Sanborn compressors
• Industrial Air compressors
• Coleman Powermate compressors
• Import Pump compressors
• Saylor-Beall compressors

Important: Many Import compressor pumps use this same style valve, but some models use metric or other non-standard compression tubing that looks nearly identical to 1/4" compression. Please verify your unloader tube size before ordering.

Installation Notes

This valve contains an internal Schrader-style valve that is depressed by the unloader piston mechanism when the compressor shuts off.

For proper operation:

• Install the valve just deep enough so the unloader piston pin contacts the Schrader valve.
• Do not overtighten or thread the valve in until it bottoms out, as this can damage the internal valve and prevent the unloader from operating correctly.
• After installation, verify that the unloader releases a temporary burst of air when the compressor shuts off.

Before Replacing Your Unloader Valve

A very common misdiagnosis is replacing the unloader valve when the tank check valve is actually the problem.

If air continues leaking from the unloader valve after the compressor has shut off and does not stop, the unloader valve is usually not defective. In most cases, the tank check valve has failed, allowing air from the tank to flow backward into the discharge line and escape through the unloader valve.

The unloader valve only vents the small amount of air trapped between the pump and the check valve. Once that air is released, the leaking should stop. If it doesn't, inspect or replace the tank check valve before replacing the unloader valve.

Need Help?

If you're unsure whether this is the correct replacement or have questions about sizing, installation, or troubleshooting, feel free to contact us. We're happy to help identify the correct part before you order.