BMW G20 G21 G22 G23 G26 G28 G42 330i 430i B48 Radiator Top Coolant Hose 8654823

BMW G20 G21 G22 G23 G26 G28 G42 330i 430i B48 Radiator Top Coolant Hose is an original cooling system component designed for modern 3 and 4 series models with the B48 engine. Thanks to its precise fit for factory installations, it ensures stable coolant flow and safe operation of the powertrain. This is a practical solution for users who expect consistency with the factory BMW design and want to keep their cooling system in proper condition.

Specifications and technical data

• SKU: 8654823
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8654823
• Substitutable numbers: 17128654823, 8654823
• Category: Coolant Hoses

Purpose and compatibility with the cooling system

The presented radiator top coolant hose is a component from the Cooling system hoses and pipes group, designed to work with the B48 engine in BMW G-series models, such as the G20, G21, G22, G23, G26, G28, and G42 in 330i and 430i versions. Its geometry and connection diameters are adapted to the factory routing, which allows for maintaining proper coolant circulation between the engine and the radiator without the need for system modifications.

A properly selected top hose minimizes the risk of leaks, air pockets in the system, and localized overheating, which directly impacts the durability of the powertrain and the stability of the operating temperature.

Technical and functional characteristics

The radiator top coolant hose in this version is a flexible component, adapted to operate under the variable thermal and pressure conditions typical for modern BMW gasoline engines. The hose design accounts for:

• resistance to high coolant temperatures and thermal fluctuations after startup and during intensive driving,
• shape stability during pressure changes in the cooling system,
• precise routing in the engine bay, limiting contact with other components.

By maintaining the factory routing of the hose, it is possible to maintain proper fluid circulation, which supports even cooling of the cylinder head and engine block and improves the predictability of the entire system's operation.

Benefits of using an original BMW hose

Using an original BMW hose in the cooling system provides a number of practical operational benefits:

• Factory fit – the hose is prepared for installation in specific BMW models, which facilitates assembly and reduces service time.
• Consistency with the cooling system design – maintaining the original routing of the hoses promotes even temperature distribution in the engine.
• Stable operation under load – the hose is adapted to operate under the thermal and pressure loads typical for the B48 unit.

The item comes from a group of used parts, which allows for economical vehicle maintenance while maintaining compliance with the factory BMW specification.

The importance of a functional radiator hose for engine safety

The radiator top coolant hose is responsible for transporting heated fluid from the engine to the radiator, which is why its condition has a direct impact on protecting the powertrain from overheating. Leaks, cracks, or deformations of the hose can lead to fluid loss, a drop in system pressure, and uncontrolled increases in operating temperature. A properly selected and functional hose helps maintain stable engine operating parameters, which translates into its longevity and the predictability of the car's behavior in city traffic and on the road.

If you want to better understand the impact of the cooling system on powertrain durability and the symptoms of overheating, it is worth reading our guide: Engine cooling system – overheating, repair, and used radiators.

Cooling system expansion and related parts

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other elements from the same group, such as additional pipes, flexible hoses, or fluid connections, check out the available parts in the BMW cooling system hoses and pipes category.

For users who pay attention to the economic and environmental aspects of vehicle operation, an interesting supplement to your knowledge might be an article dedicated to the use of recycled parts: Eco-driving: discover the benefits of used car parts. It allows you to better assess the advantages of using used components in modern vehicles.