The Mercedes-Benz OM654 engine, which made its India-debut in the E 220d LWB, will eventually make its way through the entire Mercedes-Benz India lineup, except the S Class and GLS, of course.
Mercedes’ current lineup in India, the hatchbacks—A 220d and B 200d, the sedans—C 220d, C 250d, CLA 200d and CLS 250d, the SUVs—GLA 200d, GLC 220d and GLE 250d, all expected to have the new OM654 2.0 4-cylinder turbo diesel, replacing the OM651 2.1 litre (2,143 cc) unit which has been around for almost a decade.
Globally debuted in 2016, the new OM654 is claimed to be 17% lighter and consumes 13% less fuel than its predecessor. Here’s how it compares with the OM651.
|Displacement||1,950 cc||2,143 cc|
|Displacement per cylinder||487.5 cc||537 cc|
|Bore||82 mm||83 mm|
|Stroke||92.3 mm||99 mm|
|Output (kW/hp)||143/195 @ 3,800 rpm||125/170 @ 3,000 – 4,200 rpm|
|Torque (Nm)||400 @ 1,600 – 2,400 rpm||400 @ 1,400 – 2,800|
|Compression ratio (1:)||15.5||16.2|
|Weight||168 kg||199 kg|
According to Mercedes, the fuel-saving is due to the reduction in internal friction by around 25%. This was achieved by measures such as Nanoslide coating of the cylinder walls (Mercedes’ patented technology), reduced displacement, and aluminium engine block and steel piston combination. The patented Nanoslide is also claimed to reduce CO2 emissions of up to 4%.
There’s something called as “Stepped-bowl combustion process” in the OM654, which also helps in fuel saving. It has been named after the shape of the combustion bowl in the piston. According to Mercedes, the efficiency is increased by the higher burning rate in comparison with the previous omega combustion bowl. The characteristic feature of the combination of bowl shape, air movement and injector, is its very efficient utilization of air, which allows operation with a very high air surplus. This means that particulate emissions can be reduced to an especially low level.
Additionally, Mercedes says that the new diesel engine is designed to meet future emissions legislation (RDE – Real Driving Emissions). All the components for emissions reduction are installed directly on the engine. Supported by insulation measures and improved catalyst coatings, there is no need for engine temperature management during cold starting or at low load.
The OM654 is produced in Untertürkheim (Stuttgart) in Germany and in Pune.
During the launch of E 220d, Roland Folger, MD & CEO, Mercedes-Benz India said, “The launch of the new E 220d also marks the India debut of Mercedes-Benz’s globally acclaimed, OM654 diesel engine. The new E 220d’s diesel mill promises to be more efficient, powerful, lighter and compact.”