Mercedes Sprinter Fuel Pump & Level Sensor O-Ring – Ajusa | NCV3 & VS30 | #0259971845 (2007–2024)

A worn or degraded fuel pump o-ring on a Mercedes Sprinter creates a fuel leak at the pump-to-tank interface — one of the most hazardous and immediately dangerous leaks on any vehicle. This is the Ajusa fuel pump and fuel level sensor o-ring for NCV3 and VS30 Sprinters, a direct replacement that restores a clean, fuel-tight seal at the fuel pump flange and prevents fuel loss, vapor leakage, and fire risk.

What This Part Does

The fuel pump o-ring seals the interface between the fuel pump and level sender assembly and the fuel tank at the pump access flange. It maintains a pressurized, vapor-tight seal that prevents liquid fuel and fuel vapors from escaping at the pump mounting point — a critical sealing function given the flammability of diesel fuel and the proximity of the fuel tank to the vehicle underbody. On the Sprinter, this o-ring is disturbed every time the fuel pump, fuel level sender, or fuel strainer is serviced, making it a mandatory replacement item during any fuel pump access. The seal degrades over time from exposure to fuel, heat cycling, and compression set — and a hardened or swollen o-ring that is reused during reassembly will not maintain the required seal pressure, creating an immediate or developing leak.

Common Symptoms of a Failing Fuel Pump O-Ring

• Fuel smell from underneath the van, particularly after driving or when the fuel tank is full
• Visible fuel staining or wet residue at the fuel pump flange on top of the fuel tank
• Fuel level dropping faster than normal from evaporative loss at the seal
• Fuel leak detected during an inspection or safety check at the pump mounting area

When to Replace

Replace any time the fuel pump or fuel level sender is removed — never reuse the old o-ring during reassembly. This is an inexpensive seal that is the only barrier between the fuel system and the atmosphere at the pump access point. Installing a new pump on a used o-ring is a reliable way to create an immediate fuel leak.

Fitment

• 2007–2018 Mercedes-Benz Sprinter 2500 – All engines (NCV3/W906)
• 2007–2018 Mercedes-Benz Sprinter 3500 – All engines (NCV3/W906)
• 2019–2024 Mercedes-Benz Sprinter 1500 – All engines (VS30/W907)
• 2019–2024 Mercedes-Benz Sprinter 2500 – All engines (VS30/W907)
• 2019–2024 Mercedes-Benz Sprinter 3500 – All engines (VS30/W907)
• 2019–2024 Mercedes-Benz Sprinter 3500XD – All engines (VS30/W907)

✔ Always replace o-ring when removing the fuel pump or level sender — never reuse
✔ Always verify fitment by VIN before ordering

Part Numbers

• Mercedes OEM: 0259971845 / A0259971845 / 025-997-18-45
• Cross-reference: 0009977108 / 0149978945
• Manufacturer: Ajusa — 16114700
• SKU: 0259971845