Flange Mercedes W639 Diesel OM642 Coolant Line Fitting Flange A6422000556

The Mercedes W639 Diesel OM642 Coolant Water Flange is a precise cooling system component, designed specifically for OM642 diesel engines. It is responsible for the stable flow of coolant, which supports a safe engine operating temperature and reduces the risk of overheating. Thanks to its factory geometry, the flange ensures proper fitment within the cooling system of a Mercedes W639 with a diesel engine.

Specifications and technical data

• SKU: A6422000556
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6422000556
• Substitutable numbers: A6422000556, A 642 200 05 56
• Fuel type: Diesel
• Category: Coolant Hoses

Purpose and Function in the Cooling System

The presented coolant water flange is a part of the Cooling System Hoses and Pipes group, responsible for directing fluid circulation within the diesel engine. In OM642 units installed in the Mercedes W639, it ensures a sealed connection between system sections, which is crucial for maintaining adequate pressure and uniform coolant distribution.

A correctly chosen flange helps to reduce cooling performance drops, minimizes the risk of leaks, and supports stable diesel engine operation across a wide range of loads – from city driving to long highway journeys.

Benefits of Using an Original Mercedes Part

Using a flange dedicated to the OM642 engine in the W639 model allows for the preservation of the original coolant flow characteristics. The original connection geometry translates to:

• secure fitment with other cooling system components,
• stable fluid flow under high thermal load conditions,
• reduced risk of leaks at hose connections,
• easier diagnostics and future servicing.

For Mercedes diesel owners, this means more predictable cooling system behavior and the ability to maintain operating parameters close to factory specifications.

Installation and Operational Characteristics

The coolant water flange for the Mercedes W639 with the OM642 unit is constructed to work with a Diesel fuel-based cooling system. By maintaining the original form of the connections, installation proceeds in an orderly manner, without the need for hose modifications or additional adapters.

When replacing, it is recommended to:

• inspect the condition of adjacent cooling system hoses and pipes,
• check sealing surfaces and hose clamps,
• bleed the system after filling with fresh coolant.

This approach allows for the full utilization of the benefits of the newly installed flange and reduces the risk of subsequent leaks.

Product Condition and Practical Application

The offered flange is a used part, which presents an attractive solution for users seeking a factory component at a reasonable price. A used part from the original production line retains its proper geometry and can be successfully used as a replacement for a worn or damaged flange in the cooling system of a Mercedes W639 with a diesel engine.

It is always advisable to verify the compatibility of the correct flange with the specific vehicle configuration, engine, and cooling system to facilitate subsequent installation and operation without unnecessary modifications.

Expanding Cooling System Service and Technical Knowledge

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and require other parts from the same group, such as flexible hoses, rigid pipe sections, or coolant connectors, check the available parts in the Mercedes Cooling System Hoses and Pipes category.

To better understand how thermal loads affect the durability of hoses, flanges, and other cooling system components, consult our guide: Summer Heat vs. Cooling System: Used Radiators and Fans Guarantee Savings. This will help you plan preventative maintenance and select the right components for your car.