Engine Belt Tensioner Mercedes W168 OM668 Drive Pulley Diesel Mount A6682002270

Engine Belt Tensioner Mercedes W168 OM668 Drive Pulley Diesel Mount is a component from the Tensioner and guide pulleys group, designed for the auxiliary drive system of diesel engines in models equipped with the OM668 unit. It is responsible for the stable guidance of the V-belt in the diesel engine, ensuring proper power transmission to key components and reducing the risk of slippage or noise.

Specifications and technical data

• SKU: A6682002270
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6682002270
• Substitutable numbers: A6682002270, A 668 200 22 70
• Fuel type: Diesel
• Category: Idlers & Tensioners

Purpose and function in the auxiliary drive system

The V-belt tensioner in the OM668 engine is responsible for maintaining the correct belt tension throughout the entire RPM range, which has a direct impact on the operation of the alternator, power steering pump, and other belt-driven components. In diesel units, stable belt tension is particularly important due to the higher loads and operating characteristics of the diesel engine.

A properly selected tensioner reduces belt vibration, minimizes the risk of belt skipping, and reduces the load on auxiliary bearings. In practice, this translates into smoother engine operation, a lower risk of auxiliary component failure, and more predictable behavior of the powertrain during daily use.

Benefits of using an original Mercedes component

Using a tensioner from the Tensioner and guide pulleys group sourced from the Mercedes brand allows you to maintain the factory operating parameters of the system. The component is designed for the specific belt routing geometry of the OM668 engine, which ensures that it:

• maintains the correct V-belt routing line,
• ensures predictable behavior during engine load changes,
• reduces the risk of excessive wear on the belt and guide rollers,
• supports the proper operation of auxiliary components across the entire operating temperature range.

For users of vehicles with diesel engines, this means more consistent auxiliary drive operating conditions and a lower risk of unplanned downtime resulting from belt or guide component failure.

Operational and installation characteristics

The V-belt tensioner designed for the OM668 unit is structurally adapted to the mounting system in the W168 body, which facilitates service and replacement in workshop conditions. Precise fitment for the specific diesel engine allows for maintaining the correct operating range of the tensioning mechanism without the need for modifications to other system components.

The used component is a good solution in situations where you want to maintain the manufacturer's original specifications while optimizing repair costs. Replacing the tensioner is recommended when there are visible signs of belt wear, noise from the auxiliary area, or during comprehensive belt drive service.

Application in OM668 diesel engines

The OM668 diesel engines used in the Mercedes W168 are characterized by a compact auxiliary layout, which requires the use of properly selected tensioner and guide pulleys. A precise V-belt tensioner helps maintain:

• stable belt tension at low and high RPM,
• proper cooperation with other guide rollers,
• an appropriate level of noise and vibration in the engine compartment.

Thanks to this, the auxiliary drive system in the diesel engine maintains parameters close to factory specifications, which is important for both durability and vehicle comfort.

Service expansion within the belt drive system

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 additional guide rollers, return pulleys, or other tensioners, check out the available parts in the Mercedes Tensioner and guide pulleys category.

While working in the engine compartment, it is also worth taking care of the air conditioning and heating system, especially in vehicles with a diesel engine, where stable auxiliary operation affects driving comfort. Practical tips on selecting used OEM components and service schedules can be found in the article Air conditioning and heating – part selection and maintenance for year-round comfort.