How to Replace the Check Valve on an Air Compressor

If leaking seals and service bills are distressing your compressor, it's time to face the fix. While air compressors can be as diverse as the individuals that use them, most models share some general characteristics and components. Whether you are inflating your tires or creating empires, eReplacementParts.com provides the parts, procedures and facts you need to fearlessly fix what fails you.

The check valve allows air to pass from the cylinder into the tank while preventing the air in the tank from returning to the cylinder. When the check valve is faulty, the compressor will initially function normally until the tank fills with air. At that point, the pump will attempt to restart, but the engine will produce only a “humming” noise. Similarly, if the tank is already full of air, the engine will produce only the “humming” noise without actually engaging.

Less than impressed with your compressor? Replacing the check valve may be the solution. This article will show you how to complete the repair with expert precision.   THE FACTS | THE FIX | THE FINISH ! DEPRESSURIZE THE AIR TANK.

Always depressurize the tank before servicing an air compressor. To do this, open the drain valve and wait until all of the air (and pressure) has escaped.

  REMOVING THE CHECK VALVE  [top]  1. Remove the hose clamp from the tank hose.

SPECIFIX: Crimp-style hose clamps are designed for one-time installation only. The clamps will be destroyed during the removal process, so be sure to order (or have on-hand) additional clamps for your specific repair project.

Use heavy-duty wire cutters to simultaneously cut and twist the protruding tabs of the hose clamp until the clamp breaks free.

Use your fingers (or long-nosed pliers) to remove any remaining fragments of the old hose clamp.

      2. Remove the tank hose from the check valve.

Use hose-puller pliers to remove the tank hose from the check valve.

      3. Remove the check valve from the air tank.

Use a socket wrench to loosen the check valve.

Remove the check valve from the air tank.

  INSTALLING THE NEW CHECK VALVE  [top] 4. Install the check valve in the air tank.

Thread the check valve into the air tank until it is hand-tight. (The new check valve comes with thread sealant pre-applied; additional thread sealant is not required.)

Secure the new check valve with a socket wrench.

      5. Reinstall the tank hose.

Install a new hose clamp onto the tank hose.

Install the hose onto the check valve.

Use end-nip pliers to crimp the sides of the hose clamp and secure the hose.

    THE FACTS | THE FIX | THE FINISH

A well-maintained air compressor can mean the difference between performance under pressure, and under-pressured performance. But you don't have to empty your pockets to keep your air tank full. As you just learned, repairing your air compressor is simpler than you think, especially when you follow our step-by-step guides. Not only did you refresh compression at a fraction of the cost of replacement; you have inflated your ability to fearlessly face the next fix, regardless of the pressure involved. Find your next fix here.   [top]