Smart 451 Fortwo Fuel Filler Neck Flap Cap A4517500003

The Smart 451 Fortwo Fuel Filler Neck Filler Cap Fuel Filler Neck is an original part from the Fuel Filler Necks and Pipes group, designed for the refueling system of the Smart 451 Fortwo model. The complete neck and cap assembly ensures a sealed, secure, and convenient refueling process, reducing the risk of leaks and fuel tank venting issues.

Specifications and technical data

• SKU: A4517500003
• Mark: Smart
• Condition: Used
• OEM Part Number: A4517500003
• Substitutable numbers: A4517500003, A 451 750 00 03
• Part type: Filler Neck
• Category: Fuel Tanks & Filler Necks

Purpose and Function in the Fuel System

The presented fuel filler neck is responsible for a stable connection between the fuel dispenser nozzle and the fuel tank, directing fuel through a properly shaped neck. A correctly chosen element in this section of the fuel system minimizes the risk of leaks, contamination entering the tank, and venting problems during refueling.

The original design, dedicated to the Smart 451 Fortwo, means correct mounting geometry, appropriate hose diameter, and compatibility with the factory body element placement. This ensures a smooth installation, and the entire system maintains factory routing and the aesthetics of the filler recess.

Construction of the Fuel Filler Assembly

The set includes both the filler neck and the cap, forming a functional assembly responsible for sealing and ease of use. The neck directs fuel to the tank, while the cap protects the system from moisture and dirt ingress and limits fuel vapor escape. This solution promotes stable fuel system operation and facilitates daily vehicle use.

Thanks to its construction in line with Smart's factory standards, the element works with original body mountings and filler recess covers. This is important for both safety and durability – a correctly mounted filler neck is less susceptible to mechanical damage during refueling or operation in harsher conditions.

Condition, Fitment, and Benefits of Use

The item is offered as a used part, allowing for an economical repair of the refueling system while maintaining original manufacturing quality. In practice, this means the possibility of restoring full fuel filler functionality without the need to resort to aftermarket replacements with uncertain fitment.

Using an original fuel filler neck for the Smart 451 Fortwo includes:

• maintaining factory geometry and hose routing in the filler area,
• secure cap seating and reduced risk of leaks,
• consistency with other components of the vehicle's fuel system.

Technical Support and Part Number Selection

When selecting fuel system components for the Smart 451 Fortwo, it is crucial to use manufacturer designations and reference numbers to avoid compatibility issues. This fuel filler neck has an assigned OEM part number and interchangeable numbers that facilitate verification of compatibility with a specific vehicle version.

If you want to better understand the role of the fuel filler neck in the entire fuel supply system, diagnostics, and principles of component selection by manufacturer numbers, it is worth consulting the guide: Fuel System – Injectors, Pumps, and Fuel Tank: Maintenance and Repair. The article discusses practical aspects of operation and helps to plan repairs consciously.

Expanding Repairs in the Smart Fuel System Area

If you are planning a comprehensive repair or upgrade of the fuel system area in your Smart and need other parts from the same group, such as additional sections of filler pipes, connecting nipples, or components leading to the tank, check the available parts in the category Smart Fuel Filler Necks and Pipes.