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Filler Neck Modification:

After many Sloo...w fill-ups, getting Gasoline all over the rear of my car and the ground, I modified my filler neck as follows:

Step 1

Remove the original right angle filler from the car at the rubber coupler

<--View of original filler from inside truck.

Step 2

Shown is a Filler Neck from a 1984 Ford Mustang that I purchased from a local Pick-n-Pull Wrecking Yard. Cost of the filler neck with filler cap was $10.00.

I then cut the Mustang filler neck just before the second bend from the filler cap as shown in picture.

Step 3

Install the modified Mustang filler neck into the Falcon rubber coupler and tighten clamp with the filler cap facing upwards.

Note: I attached a flat strip of aluminum from the filler neck to the car for stability.

Here's what the assembly looks like from outside the trunk.

Step 4

The next step is to attach the original filler cap back on the car. The easiest way would be to cut the original filler neck just behind the mounting bracket and re-install the part on the car and twist the cap back on. I did not use this method because I wanted to keep the filler neck in case I wanted to return this modification back to the original configuration.

First Option

I originally wired the cap to the car. This work very good and made the cap hard to steal.

This pictures shows How I wired Two lengths of wires just under the filler caps locking tabs. The first length of wire is wound around once, then twisted with approx 6 inches of wire sticking out. This is repeated once again with the second length of wire exiting 180 degrees from the first length.

Here is a view from inside the trunk with the filler cap installed on the car and the wires attached to the car and twisted but not trimmed and dressed.

Second Option

I later found a filler neck bracket from a Ranchero. this Part has the same mounting holes and can be adjusted to make the cap very hard to install and remove.

Here are the parts I used for the conversion, the Ranchero filler neck bracket is the part shown in the lower left of the picture.


This modification has been on my car since July 1998 and I'm happy with the with the results. I now pull into a Gas Station open the trunk, remove the filler cap, fill the tank at full speed without spilling, re-install the cap and close the trunk and I'm done. There is no leaks or fumes (make sure you use a non-vented gas cap) with this modifications.


Disclaimer: I am not a professional mechanic. This site is not intended to instruct or teach anyone in proper or safe methods of working, maintaining or modifying a car and the author takes no responsibility for the the use of the information contained herein.

Copyrighted 1998-2003 John Guerini

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