Carburetor Fuel Inlet Lines and Fittings

The answer to this question depends on the manufacturer and carburetor type. Most Holley carburetors have fuel inlet(s) on the side as well as Edelbrock carburetors. Many Quadrajet / Q-Jet carbs have the fuel inlet at the front, pointing to the passenger side of the vehicle and use GM fuel line fittings.

Depending on the carburetor, the connection will vary. Some carburetors use a threaded inverted flare fitting, while others use barbed fuel line fittings. Barbed fittings connect by pushing a rubber hose over the fitting and installing a clamp to secure the fitting. Inverted flare fittings use a wrench to tighten.

Depending on the fitting, the way to connect it will differ. Most carburetor fittings (such as 1/4 fuel line fittings and 5/16 fuel line fittings use a flare nut wrench, which allows the most contact around the nut to prevent damage from an overly-tight connector.

To install nylon fuel line fittings (high pressure fuel line fittings) a fuel line repair tool kit is recommended. This kit is designed to slide nylon hose onto quick connect fittings as well as high pressure clamps to secure the connection.

There are many production and aftermarket fittings. To determine what fuel line fitting you have, measure the nut (if it has one) for a size, as well as thread size (count the number of threads per inch / mm as well as measure outside diameter), barb size, and any other details. A JEGS tech representative can help you identify the fitting type from the information you share. Performance AN fittings (for example, 6an fuel line fittings) use aluminum wrenches.

The most common tool to tighten fuel line fittings in a standard combination wrench or flare nut wrench. Performance AN fittings use aluminum wrenches.

The two most common types of fuel line fittings, inverted flare and hose barb, require a wrench to unscrew them from the carburetor, fuel pump, or other fuel system components. They are disconnected by rotating them counter-clockwise with the correct size wrench.

A JEGS expert is ready to answer your questions and help you find the carburetor fuel line fittings, connectors, hoses, or adapters that you require for your specific application.