Radiator Expansion Tank BMW X3 F25 X4 F26 Overflow Tank Bottle 7823544

BMW X3 F25 X4 F26 Expansion Tank 7823544 is an original cooling system component from the expansion tanks category, designed for use in selected BMW X series models. This is an OEM solution that ensures proper operation of the cooling system, fluid pressure stabilization, and safe discharge of excess coolant. Thanks to its factory design, the tank guarantees a perfect fit in the engine bay and correct interaction with other components.

Specifications and technical data

• SKU: 7823544-1
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8616418
• Substitutable numbers: 17138616418, 8616418, 17137639464, 7639464, 17137823544, 7823544
• Category: Expansion & Overflow Tanks

Purpose and Compatibility

The presented expansion tank has been designed for BMW X3 F25 and BMW X4 F26 models, where it is responsible for compensating for changes in coolant volume. The OEM construction allows for installation in place of the original component without the need for modifications to the lines or brackets, which facilitates the mechanic's work and reduces service time.

By maintaining the original geometry of the spigots and mounting points, the tank works with factory hoses and sensors, ensuring proper fluid circulation throughout the cooling system. This is particularly important in SUV-class vehicles, where the system operates under higher thermal load.

Construction and Function in the Cooling System

The expansion tank plays a crucial role in stabilizing the pressure and level of the coolant. The appropriately designed working chamber allows for:

• compensation for the thermal expansion of the fluid during engine heating and cooling,
• maintaining a constant fluid level in the system,
• controlled bleeding and discharge of excess fluid,
• monitoring of the fluid level (depending on vehicle equipment).

The original design of the tank ensures proper internal flow, which limits the risk of localized overheating and supports stable operation of the thermostat and radiator. This translates to more predictable engine operating conditions and reduced load on other cooling system components.

Condition, Origin, and Benefits of Using OEM Parts

The offered component is a used part from a dismantled vehicle and is sold as a used BMW expansion tank. In practice, this means it is of factory origin, retains the original manufacturer's specifications, and is fully compatible with the factory solutions used in the BMW X3 F25 and X4 F26. Compared to aftermarket alternatives, an OEM part offers:

• a secure fit with factory brackets and accessories,
• compatibility with the cooling system operating parameters specified by BMW,
• material consistency with other system components.

Choosing an original tank from a dismantled vehicle is a sensible compromise between cost and maintaining the original cooling system properties, especially in vehicles used intensively or with higher mileage.

Benefits of Installation in BMW X3 F25 / X4 F26

Installing this expansion tank in a BMW X3 F25 or X4 F26 allows for the restoration of proper cooling system operation after damage, cracking, or wear of the previous component. The main benefits include:

• stable engine operating temperature due to maintaining the correct fluid level,
• reduced risk of engine overheating,
• preservation of the cooling system's original operating characteristics,
• no need for hose adaptation or additional mounting elements.

This solution is particularly recommended for collision repairs, preventative replacements, and restoring the vehicle's full functionality after a cooling system failure.

Related Products and Technical Knowledge

If you are looking for other BMW expansion tanks for various models of this brand, check out the BMW expansion tanks available in our store to select a component perfectly matched to the specific engine version and year.

For collision repairs, where engine bay and body components are damaged, it is worth consulting the guide on selecting parts from dismantled vehicles – particularly useful when planning a comprehensive repair of the cooling system and engine accessories. Practical tips can be found in the article "Body and Chassis – Collision Repairs Using Parts from Dismantled Vehicles", which discusses, among other things, the principles of safe use of used OEM parts.