The Om654m represents a significant evolution in Mercedes-Benz’s diesel engine technology. Building upon the success of its predecessor, the OM654, this modified engine incorporates a 48-volt mild-hybrid system with an Integrated Starter Generator (ISG) for enhanced performance and efficiency. This article explores the key features and advancements of the OM654M.
The Evolution of Mercedes Diesel Technology
Mercedes-Benz has a long history of innovation in diesel engine development. The OM654, introduced in 2016, marked a new era, focusing on efficiency and reduced emissions. In 2017, Mercedes furthered its commitment to electrification with the introduction of the OM656 six-cylinder diesel and the M256 six-cylinder petrol engine, both featuring mild-hybrid technology and a 48V electrical system. The OM654M builds upon this foundation, bringing the benefits of electrification to the four-cylinder diesel segment.
OM654M: Power and Efficiency Redefined
The OM654M (M for modified) distinguishes itself from its predecessor through the integration of a 48-volt electrical system and an ISG. This combination results in a power boost of 22 hp and a torque increase of 200 Nm. The ISG functions as both a starter and a generator, enabling smoother engine starts, providing assistance during acceleration, and generating electricity during deceleration. This “EQ Boost” functionality, as Mercedes calls it, improves fuel economy and reduces emissions.
ISG Integration and Transmission Enhancements
A key innovation in the OM654M is the integration of the ISG within the 9G-Tronic automatic transmission. By housing the electric motor, power electronics, and transmission cooler directly on the transmission, Mercedes has minimized weight and optimized efficiency. This streamlined design also facilitates the engine’s adaptability for use in plug-in hybrid vehicles.
Enhanced Performance with a New Crankshaft and Increased Injection Pressure
Beyond the electrification advancements, the OM654M boasts mechanical improvements. A new crankshaft and a displacement increase to 1,993 cc contribute to enhanced performance. Furthermore, the injection pressure has been raised from 2,500 to 2,700 bar, optimizing combustion efficiency. The result is an engine that delivers 265 hp and 550 Nm, a significant increase from the previous generation’s 245 hp and 500 Nm.
Emissions Control: A Commitment to Sustainability
The OM654M underscores Mercedes’ dedication to environmental responsibility. The exhaust system incorporates a NOx storage catalytic converter, a particulate filter, and two SCR catalytic converters. This comprehensive approach ensures compliance with stringent emissions regulations.
The OM654M Debut: The Facelifted E-Class
The OM654M made its debut in the facelifted Mercedes-Benz E-Class. This strategic launch highlights the engine’s importance within the Mercedes lineup. Alongside the OM654M, the facelifted E-Class also introduces the all-new M254 four-cylinder petrol engine, a member of the same engine family as the six-cylinder M256. Notably, the E-Class facelift also incorporates the M256 in the Mercedes-AMG E 53 4MATIC+ model. This powerful engine, equipped with the ISG, delivers an impressive 435 hp and 520 Nm of torque.
Conclusion: The OM654M – A Diesel Engine for the Future
The OM654M embodies Mercedes-Benz’s forward-thinking approach to diesel engine technology. By seamlessly integrating electrification and enhancing core mechanical components, Mercedes has created an engine that delivers impressive performance, efficiency, and reduced emissions. The OM654M signifies a significant step in the evolution of diesel engines, setting a new benchmark for the industry.
