BMW F10 F20 F30 LCI Fuel Return Line Pipe Hose Tube B47 Diesel Engine 8514102

The BMW F10 F20 F30 LCI B47 Diesel Fuel Return Line is an original component of the diesel fuel supply system, designed for modern BMW F-series diesel engines with the B47 engine. Thanks to its precise geometry and factory fit, the line ensures stable fuel return to the system and seamless cooperation with diesel engine ancillaries.

Specifications and technical data

• SKU: 8514102-2
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8514102
• Substitutable numbers: 8514102, 13538514102
• Fuel type: Diesel
• Category: Hoses, Lines & Pipes

Purpose and Function in the Fuel System

The fuel return line in a B47 diesel engine is responsible for the controlled drainage of excess diesel fuel from the injection rail and injectors back to the tank. In BMW F-series vehicles (F10, F20, F30 LCI), a properly functioning return line:

• stabilizes pressure in the common rail system,
• reduces the risk of air ingress into the fuel system,
• supports uniform injector operation under various engine loads,
• helps maintain the correct fuel temperature in the circuit.

This allows the B47 unit to maintain its smooth running characteristics, and the engine control unit can precisely dose fuel across the entire RPM range.

Construction and Fit for BMW with B47 Engine

This line belongs to the group of Lines, Hoses, and Tubes, specifically designed for the engine bay architecture of BMW F10, F20, and F30 LCI models. This means:

• factory routing of the line within the engine bay,
• use of connectors adapted to the B47 diesel injection system,
• appropriate material resistance to operating pressure and fuel temperature,
• compatibility with original brackets and mountings in the F-series body.

This precise fit facilitates installation and reduces the risk of leaks, which is particularly important in sophisticated common rail systems.

Benefits of Using an Original BMW Line

Using an original fuel return line in a B47 diesel engine offers tangible operational benefits:

• Stable Injector System Operation – proper fuel return flow reduces pressure fluctuations and supports uniform dosing.
• Reduced Leaks – correctly selected connectors and line diameters minimize the risk of leaks at critical points in the system.
• Improved Engine Parameter Repeatability – the diesel fuel supply system operates under conditions intended by the manufacturer, which helps maintain factory performance.
• Easier Diagnostics – using components consistent with the BMW design simplifies work for service centers and mechanics, especially during advanced fuel system tests.

Characteristics of a Used Component

The offered line is a used part, sourced from disassembly, allowing for an economical repair of the fuel system while maintaining the original BMW specification. This type of part is a good choice in situations where:

• a quick replacement of a damaged return line is necessary,
• maintaining the original fuel system geometry is important,
• the cost-to-quality ratio and compliance with the factory design are key considerations.

The fuel return line for the B47 diesel engine is suitable for both standard replacement of a damaged component and for more extensive servicing of the fuel supply system.

System Expansion – Related Parts and Technical Knowledge

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other parts from the same group, such as additional fuel lines, flexible hoses, or rigid supply pipes, check the available parts in the BMW Lines, Hoses, and Tubes category.

When working on diesel systems, it is also worthwhile to expand your knowledge about the operation of modern diesel engines and their ancillaries – an article describing practical tips for timing and injectors in popular Mercedes units might be helpful: Reliability under the star – how to care for engine ancillaries in Mercedes-Benz C-Class and E-Class. Although it concerns a different brand, it covers universal issues related to the durability of diesel engine ancillaries.