Mercedes C219 Petrol M273 Engine Expansion Tank Vent Tube Hose Pipe A2115011725

Mercedes C219 Petrol M273 Engine Expansion Tank Vent Tube Hose Pipe is an original cooling system component, specifically designed for M273 petrol units. The precisely selected geometry and diameter of the hose ensure stable discharge of excess vapors and fluid, supporting safe engine operation across a wide range of loads.

Specifications and technical data

• SKU: A2115011725
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2115011725
• Substitutable numbers: A2115011725, A 211 501 17 25
• Fuel type: Petrol
• Category: Hoses, Lines & Pipes

Purpose and technical function

The offered hose belongs to the Hoses, pipes and lines category and acts as a vent channel between the expansion tank and the cooling system in the M273 petrol engine. A properly functioning vent hose:

• stabilizes pressure in the expansion tank,
• facilitates the removal of air bubbles from the cooling system,
• reduces the risk of local overheating in the cylinder head and engine block area,
• supports the maintenance of the correct coolant level.

Thanks to its factory fitment for the petrol engine, the hose maintains appropriate flexibility and tightness under the typical operating conditions of the M273 unit.

Construction and fitment for the petrol engine

The hose has been designed for operation in the cooling system of an engine powered by petrol. This means the material is adapted to higher operating temperatures typical of petrol units, as well as contact with the coolant used in Mercedes vehicles.

Key design features of the hose include:

• a profile adapted for routing in the C219 engine bay with the M273 unit,
• ends prepared for compatibility with factory connectors of the expansion tank and cooling system,
• resistance to typical vibrations and temperature changes in the engine bay.

Such construction facilitates installation and allows for maintaining the factory routing of the hose, which is important for both reliability and service convenience.

Component condition and service application

The hose is a used original Mercedes component, which in practice means it retains its factory geometry and compatibility with the cooling system in the C219 with the M273 engine. It is a good service solution in situations where:

• the original hose has cracked or delaminated,
• there are leaks in the vicinity of the expansion tank,
• replacement of the component is necessary after dismantling other sub-assemblies in the engine area.

Using an original hose from the same design group reduces the risk of fitment issues typical of universal-shape replacements.

Benefits of using an original hose

Choosing an original vent hose for the M273 petrol engine in the C219 body brings a number of practical service benefits:

• Factory fitment – the hose is designed for a specific cooling system, which facilitates installation and minimizes the risk of material stress.
• Stable cooling system operation – proper venting helps maintain a uniform engine operating temperature, which is important for the durability of the power unit.
• Consistency with other system components – the hose works with the original expansion tank and other hoses, maintaining the factory logic of the installation routing.

System expansion – related components

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and need other components from the same group, such as cooling hoses, vent hoses, or return pipes, check the available parts in the Mercedes Hoses, pipes and lines category.

For drivers interested in a broader upgrade of the drivetrain and better component matching to their driving style, a guide article describing the selection of axle ratios and differentials may be helpful – you can find it here: Dismantled drive axles and differentials – how to choose ratios for your driving style.