Mercedes-Benz OM 138

Mercedes-Benz OM 138
Overview
ManufacturerDaimler Benz AG
Production1935 (1935)–1940 (1940)
Layout
ConfigurationNaturally aspirated Straight-4
Displacement2.5 L; 155.3 cu in (2,545 cc)
Cylinder bore90 mm (3.54 in)
Piston stroke100 mm (3.94 in)
Cylinder block materialGrey cast iron
ValvetrainOHV 2 valves per cylinder
Compression ratio20.5:1
Combustion
Operating principleDiesel
Fuel systemPrecombustion chamber injection
Fuel typeDiesel oil
Oil systemWet sump
Cooling systemWater-cooled
Output
Power output33 kW (45 PS)
Torque outputcar engines: 105.35 N⋅m (77.70 lb⋅ft)
truck engines: 112.88 N⋅m (83.26 lb⋅ft)
Dimensions
Dry weight300 kg (661 lb)
Chronology
PredecessorNone
SuccessorOM 636

The Mercedes-Benz OM 138 is a diesel engine manufactured by Daimler-Benz. In total, 5,719 units were produced between 1935 and 1940. It was the first diesel engine especially developed and made for a passenger car. The first vehicle powered by the OM 138 was the Mercedes-Benz W 138. The light Mercedes-Benz trucks L 1100 and L 1500 as well as the bus O 1500 were also offered with the OM 138 as an alternative to the standard Otto engine.