SPECIFICATIONS DESCRIPTION SHIPPING & RETURN VIDEOS & BLOGS FAQS REVIEWS
[Black,2PCS]
[Silver,2PCS]
[Black,2PCS With Hose Clamps]
[Silver,2PCS With Hose Clamps]
[Silver,3PCS With Hose Clamps]
[Black,4PCS]
[Silver,4PCS]
[Black,3PCS With Hose Clamps]
[Black]
[Black]
[Black,1/4]
[Black,5/16]
[Black,1/2]
[Black,5/32]
[Black,3/8]
[Black,9/16]
[Black]
[Black]
[Black]
[Silver,5/16]
[Silver,5/32]
[Silver,3/8]
[Silver,1/2]
[Silver,9/16]
[Silver,1/4]
[Silver]
[Silver]
[Silver]
[Silver]
[Silver]

EVIL ENERGY Fuel Check Valve One Way Inline Non Return Diesel Gasoline Black & Silver 2/4PCS

$12.99
$12.99
color: Black
Size: 3/8
Quantity: 2PCS
Add To Wish List
SKU: EVFS01272S10BK
Product Type: Fuel Check Valve

  • Instant Backflow Prevention – One-way stainless-spring design keeps fuel pressure stable and stops reverse flow.
  • Wide Fluid Compatibility – Works with gasoline, diesel, oil, air, water, and low-pressure carburetor systems.
  • Built for Harsh Conditions – 6061-T6 aluminum, anodized surface, and -22℉ to 266℉ temperature tolerance.
  • Fast & Secure Installation – Barb connection fits snugly on standard fuel hoses for leak-free setup.
  • Multiple Sizes Available – From 5/32 inch to 9/16 inch OD, ideal for custom builds and fuel system upgrades.

EVIL ENERGY checkout payment icons and shopping service
[Black,2PCS]

EVIL ENERGY Fuel Check Valve One Way Inline Non Return Diesel Gasoline Black & Silver 2/4PCS

$12.99
$12.99
[Black,2PCS]
[Silver,2PCS]
[Black,2PCS With Hose Clamps]
[Silver,2PCS With Hose Clamps]
[Silver,3PCS With Hose Clamps]
[Black,4PCS]
[Silver,4PCS]
[Black,3PCS With Hose Clamps]
[Black]
[Black]
[Black,1/4]
[Black,5/16]
[Black,1/2]
[Black,5/32]
[Black,3/8]
[Black,9/16]
[Black]
[Black]
[Black]
[Silver,5/16]
[Silver,5/32]
[Silver,3/8]
[Silver,1/2]
[Silver,9/16]
[Silver,1/4]
[Silver]
[Silver]
[Silver]
[Silver]
[Silver]

EVIL ENERGY Fuel Check Valve One Way Inline Non Return Diesel Gasoline Black & Silver 2/4PCS

$12.99
color: Black
Size: 3/8
Quantity: 2PCS
SPECIFICATIONS

Brand EVIL ENERGY
Function One-Way / Non-Return Check Valve
Available Sizes (Hose Barb OD) • 5/32" (4 mm)
• 1/4" (approx. 6 mm)
• 5/16" (8 mm)
• 3/8" (10 mm)
• 1/2" (12 mm)
• 9/16" (14 mm)
Connection Type Hose barb on both ends, secured with hose clamps
Valve Body Length 24 mm (0.94")
Barb Length 17.8 mm (0.7"), shown on the 1/4" size
Material 6061-T6 Aluminum Alloy
Finish / Color Anodized, black or silver
Internal Parts • 304 stainless steel spring
• NBR O-ring
• NBR gasket
• Aluminum alloy check valve core
Minimum Upstream (Opening) Pressure 0.2 bar (2.9 psi)
Working Pressure Range 0.2–6 bar (2.9–87 psi)
Operating Temperature -22℉ to 266℉ (-30℃ to 130℃)
Media Compatibility Gasoline, Diesel, Oil, Air, Water (Not for Methanol)
Flow Direction Marked by the arrow on the valve body
Package Options • 2PCS or 4PCS check valves
• 2PCS with 4 hose clamps
• 3PCS with 6 hose clamps

DESCRIPTION

Inline Fuel Check Valve

Inline Fuel Check Valve for Carbureted and Low-Pressure Fuel Systems

This one-way inline check valve keeps the fuel system stable and protected. Built from 6061-T6 aluminum with a corrosion-resistant anodized finish, it opens in one direction only through an internal stainless steel spring, holding pressure in the line and stopping fuel from draining back when the engine is off. Barb ends push straight onto standard fuel hose, so it suits carbureted and low-pressure fuel systems on street, off-road, marine and small-engine setups.

EVIL ENERGY inline fuel check valve 2PCS installed on a fuel line for one-way flow

2.9 PSI

Opening pressure

87 PSI

Maximum pressure

6061-T6

Anodized aluminum

-22 to 266℉

Operating range

Sizing

Which Fuel Check Valve Size Fits Your Hose?

Pick the size that equals the inside diameter of the hose. A 5/16" fuel hose takes the 5/16" check valve.

5/32"

4 mm barb

1/4"

≈6 mm barb

5/16"

8 mm barb

3/8"

10 mm barb

1/2"

12 mm barb

9/16"

14 mm barb

Fuel check valve working principle showing open flow and closed backflow

How it works

How the One-Way Fuel Check Valve Works

When upstream pressure reaches the minimum opening pressure, the spring compresses and the valve opens, letting fuel pass in the arrow direction. The moment flow reverses, the spring pushes the valve shut and no fuel can pass backward, so the line stays full between drives and the pump never has to re-prime an empty hose.

Inside

What Is Inside the Aluminum Check Valve

Every valve has just four working parts: an aluminum alloy valve core, a 304 stainless steel spring that won't rust, an NBR gasket for the seat and an NBR O-ring that seals the two body halves. The 6061-T6 housing is anodized to stand up to road salt, moisture and engine-bay heat from -22℉ to 266℉.

Exploded view of the inline check valve with NBR O-ring, NBR gasket and 304 stainless steel spring
1/4 inch fuel check valve dimensions with 24 mm body and 17.8 mm hose barb

Dimensions

Dimensions of the Inline Fuel Check Valve

The valve body measures only 24 mm (0.94") across the hex, and each barb runs about 17.8 mm (0.7") on the 1/4" size, which gives a hose clamp plenty of room to grip. The small footprint lets the check valve sit inline next to a carburetor, tank outlet or pump without extra brackets.

Installation

How to Install the Fuel Check Valve with Hose Clamps

Four steps to install an inline fuel check valve with hose clamps

1

Cut the hose

Cut the fuel line squarely where the valve will sit, close to the component that needs to stay primed.

2

Fit the clamps

Slide a hose clamp onto each hose end before installing the valve.

3

Push the valve on

Point the arrow toward the engine or carburetor, then push each barb fully into the hose.

4

Tighten and check

Tighten both clamps over the barbs, prime the system and check for leaks.

Use fuel-rated hose such as NBR fuel hose, and keep spare clamps from the hose and tube management range on hand.

Applications

Where to Use an Inline Fuel Check Valve

Fuel check valve applications on fuel lines, air lines and diesel supply hoses

Carbureted engines

Keeps the line full after shut-off, so the float bowl refills faster and long cranking goes away. Pairs well with a 12V carburetor fuel pump.

Diesel supply lines

Holds prime in low-pressure lift pump and filter lines on trucks, tractors and generators, so fuel doesn't drain back to the tank overnight.

Auxiliary tanks

Stops fuel siphoning between a main tank and an auxiliary fuel tank when the transfer pump is off.

Marine and small engines

Fits outboard, mower, ATV and generator fuel hoses down to 5/32", plus air and water lines around the shop.

Choose your pack

Pack Options for the Fuel Check Valve

2PCS

A pair of check valves for one fuel line and a spare, or two separate lines.

Ready to install

2PCS with clamps

Two valves plus 4 hose clamps, everything needed for one complete install.

3PCS with clamps

Three valves and 6 hose clamps for multi-line builds such as feed, return and vent.

4PCS

Four valves for fleets, shop stock or plumbing several small engines.

Know the limits

When Not to Use This Fuel Check Valve

Choose a different part when the system falls outside these ratings.

Above 87 PSI

High-pressure EFI and direct-injection fuel systems exceed the 6 bar working range. Use a check valve rated for that pressure.

Methanol fuel

The NBR seals are not intended for methanol. Choose a valve with seals rated for alcohol fuels.

AN-fitting systems

These ends are barbs for push-on hose. For threaded AN plumbing, see hose barb fittings and adapters to step between hose and AN lines.

SHIPPING & RETURN

Brand Summary

Policy Details
Cancellation Policy Orders can be canceled within 48 hours of placement. Refund processed in 3-5 business days.
Returns Policy Returns accepted within 180 days. Full refund within 90 days; 15% fee for 90-180 days.
Non-Returnable Items Only regular-priced items are eligible for refunds; sale items are non-refundable.
Refund Processing If no refund received, check your bank/credit card. For ongoing issues, contact support@ievilenergy.com.

Return Reasons

  1. Quality Issues: Provide photos/videos; we cover return shipping.
  2. Wrong Item Ordered: Buyer covers return shipping; email within 30 days.
  3. Change of Mind: Buyer covers return shipping; email within 30 days.
  4. Shipping Damage: Inspect packages; do not sign for damaged items.
  5. Incorrect Item Shipped: Contact within 7 days.

Price Protection Policy

Effective from August 25, 2024. Price drops within 7 days of purchase can be claimed.

Disclaimer

EVIL ENERGY reserves the right to interpret, modify, or terminate this policy in accordance with applicable laws and regulations.

If you need further information or assistance, feel free to ask!

VIDEOS & BLOGS

Product Videos

×
FAQS

Q: Which way should the arrow on the fuel check valve point?

A: Toward the engine, carburetor or wherever the fuel is meant to go. The arrow shows the only direction fuel can flow. If it’s installed backward, the valve stays closed and the engine won’t get fuel.

Q: Which size fuel check valve do I need for 5/16" fuel hose?

A: The 5/16" (8 mm) valve. Each size refers to the barb’s outside diameter, which should match the inside diameter of the hose. A barb one size too large is hard to push on and can split the hose; one size too small will leak even with a clamp.

Q: What does a one-way fuel check valve actually fix?

A: Fuel draining back to the tank after shut-off. Once the line is empty, the pump has to refill it before the engine starts, and on a carbureted engine that shows up as long cranking after the truck has sat. The check valve holds fuel in the line, so the next start is quicker.

Q: What pressure does the inline check valve need to open?

A: About 2.9 PSI (0.2 bar). Any electric or mechanical fuel pump easily exceeds that. Gravity-fed setups with very little head pressure may not open it reliably, so test before relying on it.

Q: Can the fuel check valve be used on a fuel-injected engine?

A: On low-pressure systems, yes. The working range tops out at 87 PSI (6 bar), which covers carbureted engines and many port-injection systems. High-pressure EFI above that, and direct-injection systems, need a valve with a higher rating.

Q: Can I use the aluminum check valve with E85 or methanol?

A: Not with methanol; the NBR seals aren’t intended for it. For E85, choose a valve with seals rated for alcohol fuels. Gasoline, diesel, oil, air and water are all within its rating.

Q: Can the check valve stop fuel siphoning from a transfer tank?

A: Yes. That’s one of its most common uses. Install it in the line between the tanks, arrow pointing in the direction of transfer, so fuel can’t run back when the pump stops.

Q: Why is my engine still hard to start after installing the fuel check valve?

A: Check these first:

  • the arrow points the wrong way
  • the valve is installed far from the carburetor, so the hose after it still drains
  • a hose clamp leaks air

If all three check out, the cause may not be drain-back at all. A weak pump or a dirty filter produces the same symptom, so see the fuel filters as a next step.

Q: Why use hose clamps if the barbs grip the hose?

A: Barbs alone can hold at rest, but fuel pressure, heat cycles and vibration slowly work the hose loose. A clamp over each barb keeps the joint sealed for years. The 2PCS and 3PCS packs with clamps include everything for the job.

Q: How do I know if the fuel check valve has failed?

A: The usual sign is that the old symptoms come back, such as long cranking or a line that runs empty overnight. Remove the valve and blow through it gently. Air should pass only in the arrow direction. If it passes both ways or neither way, replace it.

Q: How often should an inline fuel check valve be replaced?

A: There’s no fixed interval. Inspect it whenever you service the fuel filter or the carburetor. Replace it if the hose ends have hardened, the valve no longer seals in the blow-through test, or you’re changing fuel types.

REVIEWS

RELATED PRODUCTS

Example product title
$9.69
$9.69
Example product title
$9.69
$9.69
Example product title
$9.69
$9.69
Example product title
$9.69
$9.69
Example product title
$9.69
$9.69
Example product title
$9.69
$9.69

RECENTLY VIEWED PRODUCTS