What is a fuel filler neck?
The fuel filler neck is a solid piece of formed steel that joins the fuel filler inlet (where the gas cap attaches to) and the rubber fuel fill hose to the gas tank in the fuel system. It is sealed using a steel hose clamp to prevent any fuel leakage. Inside the fuel tank filler neck, you’ll find a one-way valve allowing fuel through but preventing other objects from entering the tank, such as a siphon hose.
Over time, the fuel filler neck collects debris and dirt and can start to rust, forming leaks. The rubber hose can also become weather-cracked, causing further leakage. When this happens, you’ll need a replacement neck installed.
How do I know if my fluid filler neck needs replacing?
Because the fuel filler neck is located in an inaccessible area, it can be hard to determine when it needs replacing. As such, there are some common symptoms to watch out for if it’s time to replace it:
Leaking fuel or other chemicals
Below-average performance
How often should you change your fuel filler neck?
The fuel filler neck on a vehicle is designed to last a lifetime, so there’s no set replacement interval. However, with its metal construction, rust is one of the most common causes of a faulty fuel filler neck that needs to be replaced.
When you take your car for regular maintenance
, ask your mechanic to check the fuel filler neck. Problems are easier to fix when caught early. Can I replace the fuel filler neck myself?
Even if you’re car-savvy and have experience under the hood, replacing the fuel filler neck is a complicated process that takes time and a fair bit of equipment. As such, it’s not a great DIY project: calling your local auto body repair shop and leaving it to a professional mechanic is recommended.