Mercedes W639 W906 Engine Oil Pump OM651 Engine Lubrication Unit A6511801400

Mercedes W639 W906 Engine Oil Pump OM651 Engine Lubrication Unit is an original component from the Oil pumps and parts group, designed for the lubrication system of Mercedes power units. The OEM design ensures proper oil pressure, stable lubrication, and safe engine operation under load. Using this component allows for an economical, yet technically correct repair of the lubrication system.

Specifications and technical data

• SKU: A6511801400
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6511801400
• Substitutable numbers: A6511801400, A 651 180 14 00, A6511811801, A 651 181 18 01, A6511801301, A 651 180 13 01, A6511810512, A 651 181 05 12, A6511810312, A 651 181 03 12
• Fuel type: Petrol
• Category: Oil Pumps & Parts

Purpose and role in the lubrication system

The engine oil pump is responsible for forcing oil circulation through lubrication channels, bearings, and mating friction surfaces. In the case of Mercedes power units, a correctly selected pump is crucial for:

• maintaining stable oil pressure across the entire RPM range,
• protecting bearings, the crankshaft, and the timing system from accelerated wear,
• preventing overheating of components operating under heavy loads,
• maintaining the proper durability of the entire engine.

Selecting a pump compatible with the power unit and fuel type is particularly important in modern designs, where operating tolerances are very narrow and the lubrication system works in conjunction with advanced control electronics.

Technical characteristics and compatibility

The presented oil pump belongs to the Oil pumps and parts group and has been designed for use in Mercedes vehicles. Using an original OEM design means:

• maintaining factory oil flow and pressure parameters,
• proper fitment to the engine block and the pump drive system,
• compatibility with accessories and oil channels specified by the manufacturer.

The product has a dedicated part number and a set of interchangeable numbers, which facilitates clear identification in service catalogs and selection for a specific engine version. This allows for precise verification of compatibility with a given vehicle before installation.

Condition, origin, and service application

The pump is a used component, which allows for reduced repair costs while maintaining the manufacturer's original specifications. Such components are commonly used in:

• routine lubrication system repairs following a drop in oil pressure,
• engine overhauls where wear of pump components has been identified,
• service centers specializing in Mercedes vehicles, where compliance with the factory design is a priority.

Using an original oil pump in place of a worn or damaged component restores proper engine operating parameters and reduces the risk of more serious failures resulting from insufficient lubrication.

Benefits of using an original Mercedes oil pump

Choosing this oil pump for a Mercedes translates into a number of practical service benefits:

• Factory fitment – no need for modifications, drilling, or adjusting mounts.
• Consistency with service documentation – easier diagnostics and maintenance in the future.
• Stable lubrication system performance – essential for intensive use and high mileage.

For workshops and individual users, this means faster installation, a lower risk of post-repair issues, and maintaining engine performance characteristics in line with the manufacturer's specifications.

Related lubrication system components and further expansion

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and need other elements from the same group, such as other pumps, pump drive components, or additional lubrication system parts, check the available parts in the Mercedes oil pumps and parts category.

For major repairs, especially after collisions or mechanical failures, it is also worth paying attention to the condition of bodywork elements and powertrain mounts – practical tips and procedures can be found in the article Bodywork and chassis – post-accident repairs using salvaged parts, which helps in planning work using used OEM parts.