Where is the fuel pump located on a Mercedes 500 sec?

The fuel pump of a Mercedes 500 SEC, especially those of the 1980s and early 1990s (this is part of the W126 chassis) is normally under the car, towards the rear axle, on the passenger side. It is simply mounted directly in front of the rear fuel tank as well as the fuel filter and the fuel accumulator on a protective bracket or housing.

In order to access it, you need to raise the car safely and search under it towards the area of the rear wheel. It is an external (inline) electric fuel pump and not one inside the fuel tank as is the case with many newer cars. When you hear a whining sound at the rear of the car or when there is a fuel delivery problem, this is mostly the point where trouble begins.

Disconnect the battery whenever possible when working on the fuel system and observe safety rules when handling fuel parts.