Mercedes Benz Celebrates 75 Years of Diesel Engines

Fifty-years after Carl Benz invented the petrol-powered automobile, the W 138 series 260 D was presented at the launch as the first series-production passenger car with a diesel engine. In fact, production began near the end of 1935 an the diesel-fueled vehicle was unveiled to the public in February 1936 at the International Motorcycle and Automobile Exhibition in Berlin, Germany.

The revolutionary model was powered by a 2.6-litre OM 138 four-cylinder engine with the Mercedes-Benz pre-chamber system and a Bosch injection pump. The mill developed 45 hp (33 kW) at 3,200 rpm and was installed in the chassis of the petrol-powered Mercedes-Benz 200 that had its wheelbase extended.

Considering the relative scarcity of diesel filling stations at the time, the model came with an impressive total range of 400 kilometers (250 miles) initially, which was eventually increased to no less than 500 kilometres (310 miles) or more after a model upgrade in 1937. Another novelty was introduced in early 1938, in the form of electrically heated glow plugs which facilitated starting of the cold engine.

For holders of a passenger transport licence, diesel fuel was less than half the standard cost of petrol, so the 260 D became the vehicle of choice for the emerging taxi fleets across Germany.

The 260 D was a major success story for Mercedes-Benz, with no less than 1967 units produced from 1936 until 1940. For private buyers, it became the long distance car of choice, so there were still plenty in service during the 1950s.

Over the years, Mercedes continued to develop its diesel technology, introducing the first five-cylinder diesel car in the 240 D 3.0 in 1974 and common-rail injection on their 1997 C 220 CDI.