Mercedes-Benz OM 312 engine

The Mercedes-Benz OM 312 was an inline six-cylinder, water-cooled four-stroke diesel engine that Daimler-Benz built for its postwar light trucks, and it stands at the start of the small OM 300 series. It grew out of the prewar OM 302: the seven crankshaft main bearings were kept, but the cylinder spacing was made uneven to suit the production equipment left over from the Opel Blitz engine, which Daimler-Benz had been obliged to build under licence from 1942. The engine used prechamber injection, and with a bore of 90 mm and a stroke of 120 mm it displaced 4,580 cubic centimetres. It first produced 90 PS (66 kW), and from 1956 a higher compression, higher speed and revised valve timing raised that to 101 PS (74 kW). Careful testing was possible only because the L 3250 truck was finished a year later than planned, and a turbocharged version for special vehicles followed in 1954.