Ford Transit Mk8 Coolant Expansion Overflow Tank Fluid Bottle BK21-8K218-AG

Ford Transit Mk8 Coolant Expansion Overflow Tank Fluid Bottle is an original cooling system component from the Expansion tanks group, designed for diesel engine vehicles. It ensures stable operating conditions for the power unit by maintaining the correct coolant level and compensating for volume changes during operation.

Specifications and technical data

• SKU: BK21-8K218-AG-1
• Mark: Ford
• Condition: Used
• OEM Part Number: BK21-8K218-AG
• Substitutable numbers: 2036675, BK218K218AH, BK21-8K218-AH, BK21-8K218-AG, BK218K218AG
• Fuel type: Diesel
• Part type: Coolant Expansion Tank
• Category: Expansion & Overflow Tanks

Purpose and function in the cooling system

The presented expansion tank has been specifically designed for the cooling system of Ford Transit Mk8 diesel vehicles. Its task is to safely collect excess coolant as the temperature rises and return it to the circuit after cooling, which promotes stable engine operation and reduces the risk of overheating.

Thanks to a properly shaped working chamber and prepared connection ports, the tank works with the factory hose system, maintaining proper fluid circulation and allowing for monitoring of the working medium level.

Original origin and fitment

As a Ford brand component, the expansion tank is structurally matched to the factory mounts and the cooling system of the Transit Mk8. This means predictable fitment with brackets in the engine bay, correct hose routing, and compatibility with equipment used in diesel units.

Original origin helps maintain cooling system performance parameters consistent with the vehicle manufacturer's specifications, which is important for both engine durability and operating temperature stability in urban conditions and under loads typical for commercial vehicles.

Performance characteristics and installation

The item comes from a group of used parts, which allows for economical cooling system repair while maintaining a design consistent with the factory solution. The tank is intended for installation in place of the original component, without the need for bodywork modifications or cooling system reconstruction.

When replacing, it is recommended to:

• check the condition of the fluid supply and return hoses,
• verify the tightness of connections after installation,
• bleed the cooling system in accordance with the service procedure for diesel engines.

Benefits of using an original expansion tank

Using this expansion tank in a Ford Transit Mk8 allows you to maintain the consistency of the cooling system with the manufacturer's design, which translates into stable engine operating temperature and predictable vehicle behavior under various load conditions. A properly selected component reduces the risk of leaks, facilitates fluid level monitoring, and supports trouble-free operation of the diesel unit.

If you are planning a comprehensive repair or upgrade of the cooling system area in your Ford and need other items from the same group, such as additional tanks, auxiliary elements, or related components, check the available parts in the Ford expansion tanks category.

For drivers interested in a broader perspective on selecting original used parts, identification procedures using catalog numbers, and the impact of such solutions on vehicle durability, the guide article BMW – sports performance and precision. How do original used parts extend the life of the Bavarian icon?, which discusses practical aspects of using components from the secondary market, may be helpful.