Why Use a Check Valve?

A one-way check valve prevents reverse flow inside your system, helping maintain fuel pressure, improve startup consistency, and protect sensitive components from unwanted backflow.

Because “it’ll probably hold pressure overnight” is usually the beginning of another unnecessary garage session. If this is the wrong size that you are not looking for? Click on the “buy” link and choose from multiple AN sizes

Learn how to install AN fittings like this on our DIY article

Features

• 3/8-inch inline check valve
• One-way non-return flow design
• Lightweight aluminum construction
• Black anodized corrosion-resistant coating
• Precision-machined internal sealing surfaces
• Compact inline installation design
• Supports fuel, oil, air, coolant, and vacuum applications
• High-flow internal passage design
• Durable and leak-resistant construction

Size: 3/8 inch (9.5 mm) OD, with 3/8 inch barb inlet and outlet for simple connection.

Common Applications

• Fuel system anti-drainback setups
• Inline fuel pump systems
• Turbo vacuum routing
• Boost control systems
• Catch can plumbing
• Brake booster vacuum systems
• Oil feed and return routing
• Air compressor and pneumatic systems
• Custom engine bay plumbing

Specifications: Opening pressure: 3 PSI; Maximum working pressure: 150 PSI. Operating temperature range: -22℉ to 266℉, ensuring stable performance under both low and high temperatures.
Subject matter: Made of high-strength 6061-T6 aluminum alloy, the check valve is black anodized for enhanced corrosion and wear resistance.

Perfect for Performance Builds

Modern turbocharged and high-performance vehicles rely heavily on stable pressure and controlled fluid routing. A properly installed check valve helps maintain system efficiency while reducing pressure loss and unwanted reverse flow issues.

Especially important on builds where the fuel system has more fittings than actual horsepower.

Easy Inline Installation

The compact design allows the valve to fit cleanly into tight engine bays, underbody routing, or custom fabricated systems. Its lightweight construction also makes it ideal for motorsports and racing applications where reliability matters without adding unnecessary bulk.

Feature: This diaphragm-style fuel line check valve is equipped with a chrome steel spring that permits fluid to float in just one direction, effectively preventing fuel backflow and maintaining stable system pressure.
Application: The EVIL ENERGY fuel check valve is widely utilized in carburetor and low-pressure fuel systems. It’s compatible with quite a lot of media such as fuel, oil, coolant, air, diesel, methanol, ethanol, and E85.

Why Choose EVIL ENERGY?

EVIL ENERGY continues to be a popular choice for enthusiasts looking for affordable and dependable fuel system and plumbing hardware. Their fittings and inline components are designed to handle modern performance demands while keeping your engine bay clean, functional, and leak-free.

Mostly leak-free anyway. We all know one fitting still somehow sweats fuel no matter what you do.