Replacing Your Car's Fuel Tank Filler Neck: A Step-By-Step Guide

The fuel tank filler neck is an essential component of a vehicle's fuel system, facilitating the filling of the fuel tank. Over time, the filler neck may corrode or become damaged, necessitating its replacement to ensure the vehicle's optimal performance. This process involves removing the old filler neck and installing a new one, requiring a suitable replacement part and some mechanical expertise. The complexity of the task varies depending on the vehicle's make and model, and it is important to consult vehicle-specific instructions or seek professional assistance if needed.

Filler neck parts

Filler necks are available in a variety of sizes and materials. They are commonly made from mild steel, stainless steel, or aluminium. The diameter of filler necks typically starts at 1.75 inches, with options available in a range of sizes up to 4 inches or more.

Filler necks can be threaded or welded, and some come with additional components such as caps, hoses, and grommets. Threaded filler necks have bungs available in different heights, which can be welded to a gas tank or connected to a filler hose. Weld-in filler necks are available in various sizes and materials, including cold-rolled steel, aluminium, and stainless steel.

Filler neck kits are also available for specific vehicle makes and models, such as Ford, GM/Chevy, and Dodge/Ram. These kits include all the necessary components for installation and are designed for a perfect fit and easy installation.

Threaded fuel filler necks

Tanks, Inc. offers a range of threaded fuel filler bungs, including:

• 3" Tall Mild Steel Threaded Fuel Bung
• 3" Tall Stainless Steel Fuel Bung
• 1.25" Tall Bung with a 1" ID
• 2-1/4" OD x 3" Tall Fuel Filler Bung w/ Vent Fitting

In addition, Tanks, Inc. also offers a flanged fuel neck with a threaded neck as another option for your fuel filler needs.

If you're looking for a more affordable option, Affordable Street Rods provides a range of fuel filler necks, including:

• Low Profile Threaded Aluminum Filler Neck and Cap - FN-TAC
• Filler Neck with Aluminum Cap - FN-CC
• Pop Up Aluminum Cap and Neck - PU3C
• 2" Tall Bolt-On Fuel Filler Neck Kit with Aluminum Cap - PBC-2
• 3" Tall Bolt-On Fuel Filler Neck Kit with Aluminum Cap - PBC

These options from Affordable Street Rods provide a cost-effective solution for replacing your fuel tank filler neck, with a variety of features to choose from.

Fuel filler hose

The fuel filler hose is a crucial component of the fuel system, facilitating the transfer of fuel from the gas tank to the engine. Here's a comprehensive guide to help you understand the process of replacing a fuel filler hose:

Types of Fuel Filler Hoses:

Before replacing a fuel filler hose, it's important to understand the different types available:

• Straight Fuel Filler Hoses: These hoses are designed to connect directly to the fuel tank and filler neck without any bends or elbows. They are commonly available in various diameters, ranging from 3/16" to 2-1/2" or 5mm to 63.5mm.
• Elbow Fuel Filler Hoses: Elbow hoses are used when there is a need to navigate around obstacles. They come in different angles, such as 30 degrees, 45 degrees, 60 degrees, 90 degrees, and more. Similar to straight hoses, they are available in various diameters to fit specific applications.

When replacing a fuel filler hose, you might need to use couplers or joiners to connect hoses of different diameters. Couplers and joiners are available in a wide range of size combinations to ensure a proper fit. For example, a 5/16" to 1/4" coupler is used to connect a 5/16" hose to a 1/4" hose.

Now, let's outline the steps involved in replacing a fuel filler hose:

• Park the Vehicle: Find a safe and well-ventilated area to park your vehicle. Engage the parking brake and ensure the engine is turned off and cooled down.
• Prepare the Workspace: Place a suitable container under the fuel filler hose to catch any spilled fuel. Chock the wheels for added safety.
• Access the Fuel Filler Hose: Refer to your vehicle's repair manual to locate the fuel filler hose and its mounting points. This may involve removing body panels or interior trim pieces for access.
• Disconnect the Old Hose: Carefully disconnect the old fuel filler hose from the fuel tank, filler neck, and any other connections. Take note of the routing and any clamps or fasteners used.
• Clean the Area: Before installing the new hose, clean the surrounding area and connections to remove any dirt, debris, or residue.
• Install the New Hose: Position the new fuel filler hose, ensuring it follows the same routing as the old hose. Secure the hose using appropriate clamps or fasteners.
• Reconnect Other Components: Reinstall any components that were removed for access, such as body panels or interior trim.
• Refuel and Test: Once the new hose is installed, refuel your vehicle and check for any signs of leaks around the fuel filler hose and connections.

To ensure the longevity of your fuel filler hose and the overall health of your fuel system, consider the following maintenance tips:

• Regularly inspect the fuel filler hose for any signs of cracks, leaks, or deterioration.
• Keep the area around the fuel filler hose and neck clean and free of debris.
• Use compatible and high-quality fuel system components, including the fuel filler hose, clamps, and seals.
• Refer to your vehicle's maintenance schedule for specific recommendations regarding fuel system maintenance.

Filler neck buckets

When selecting a filler neck bucket, it is crucial to consider the angle of the filler neck and choose a bucket with a matching angle. Filler neck buckets are available in various angles, including 21 and 22 degrees, to ensure a seamless fit with the fuel filler neck.

In addition to filler neck buckets, there are also RV filler neck surrounds designed specifically for recreational vehicles. These surrounds provide an extra layer of protection and are available for various RV models, including Champion, Fireball, Fleetwood, Georgie Boy, Mobile, Pace Arrow, Southwind, Sportcoach, Tioga, Transvan, and Winnebago.

When replacing a filler neck bucket, it is important to refer to the vehicle's service manual or seek guidance from a qualified mechanic to ensure the correct part is selected and installed properly, ensuring the fuel system's safety and functionality.

Filler neck grommets

When replacing a fuel tank filler neck, it is important to also replace the grommet to ensure a proper seal and prevent fuel leaks. The grommet is a small, yet crucial, component that fits between the fuel filler neck and the fuel tank, acting as a seal to prevent fuel from leaking out.

You can purchase filler neck grommets from a variety of automotive retailers, including online stores like Amazon and O'Reilly Auto Parts. When buying a replacement, it is important to ensure you get the correct size and type for your specific vehicle. The inside and outside diameters of the grommet need to match the dimensions of your filler neck for a proper fit.

Some vehicles that commonly require filler neck grommets include the Ford F-100, F-250, and F-350 pickup trucks from 1957 to 1969, as well as the Chevrolet/GMC models from 1967 to 1970. It is always recommended to refer to your vehicle's specific make, model, and year when purchasing a replacement grommet to ensure compatibility.

Frequently asked questions