BMW F01 F02 F03 Expansion Tank Filler Neck Tube 7578663

BMW F01 F02 F03 Expansion Tank Filler Neck 7578663 is an original cooling system component designed for the 7 Series models, ensuring stable fluid supply to the expansion tank. Thanks to its factory geometry and perfect fit for BMW construction, this expansion tank filler neck allows for proper coolant circulation and hassle-free system operation.

Specifications and technical data

• SKU: 7578663
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7578663
• Substitutable numbers: 7578663, 17137578663, 7647275, 17137647275
• Category: Expansion & Overflow Tanks

Purpose and Function in the Cooling System

The filler neck is responsible for the safe and controlled delivery of coolant to the expansion tank, which is crucial for maintaining stable pressure in the engine's cooling system. In BMW F01, F02, and F03 models, a correctly selected component in this section helps reduce the risk of air ingress, leaks, and uneven system operation.

The original design ensures:

• proper fluid routing within the engine bay,
• consistency with the factory placement of the expansion tank,
• maintenance of cooling system operating parameters as intended by the manufacturer.

Compatibility with BMW F01, F02, F03

This component has been specifically designed for the body and engine bay architecture of the F-generation BMW 7 Series, resulting in a precise fit for mounting points and other cooling system components. This ensures an organized installation process without the need for modifications to other parts.

The filler neck works in conjunction with the factory expansion tank, maintaining the original routing of hoses and the manufacturer's intended method for filling and bleeding the system.

Characteristics of an Original BMW Part

As a part within the Expansion Tanks group, the filler neck is structurally adapted to the thermal and pressure requirements of the BMW cooling system. An original solution signifies compliance with factory quality standards and predictable material behavior under typical engine operating conditions.

Using an OEM part helps maintain consistency with other system components, which is particularly important when servicing premium vehicles where both functionality and compliance with the manufacturer's technical documentation are key.

Practical Benefits of Using the Filler Neck

Using a dedicated filler neck in BMW F01–F03 models offers a range of practical service and operational benefits:

• organized hose routing in the engine bay,
• easier filling and level checking of coolant in the expansion tank,
• reduced risk of leaks at connection points,
• maintenance of the factory logic for coolant hose routing.

For workshops and owners, this translates to more predictable installation and the ability to maintain the cooling system in a configuration close to its factory state, promoting stable engine operation.

Expansion and Modernization of the BMW Cooling System

If you are planning a comprehensive repair or modernization of the cooling system area in your BMW and require other parts from the same group, such as supply hoses, connecting nipples, or expansion tanks themselves, check the available parts in the BMW Expansion Tanks category.

Owners of older F-series models, considered youngtimers, may also be interested in a practical guide on using used components in the vehicle restoration process – more information can be found in the article Second Life for Youngtimers – How Used Car Parts Revitalize Cars from 1998–2012.