Mercedes-Benz OM 5 diesel engine
|Daimler Benz AG|
|Production period:||1928 to 1932|
|Manufacturer:||Daimler Benz AG|
|How it works:||diesel|
|displacement:||8572 cm 3|
|Fuel supply:||indirect injection|
|Previous model:||OB 2|
The OM 5 is a diesel engine of Daimler-Benz AG . It was introduced in 1927 as the drive for the L 5 truck , the series production started in 1928. The successor models were produced from 1932.
The OM 5 is a six-cylinder in-line engine. It is a four - stroke diesel engine with prechamber injection , water cooling and pressure circulation lubrication and side, spur gear driven camshaft and seven crankshaft bearings. Bore and stroke are 105 mm × 165 mm, resulting in a displacement of 8572 cm 3 . He makes 60 hp (44 kW) at 1300 min -1 .
The previously competing companies Benz & Cie. and Daimler-Motoren-Gesellschaft had already independently developed truck models of the 5-tonne class that were powered by diesel engines. The two companies merged in 1926 to Daimler-Benz AG , which continues to produce trucks. The diesel engine had not yet prevailed as a vehicle drive in 1927, the engine model OB 2 from Benz & Cie. it had not been produced in significant quantities. In the new model range of Daimler-Benz AG, the light and medium-duty trucks of the 1.5-tonne and 3.5-tonne class were initially only equipped with gasoline enginesoffered. The L 5 truck of the 5-tonne class was initially the only Daimler-Benz truck to be offered with a diesel engine. Alternatively, the gasoline engine M 36 with 100 hp (74 kW) was still available for this truck.
The diesel engine has the disadvantage over the gasoline engine that its displacement is lower. This fact benefited truck manufacturers in the 1920s, who offered no diesel engine in their vehicles. Their vehicles were more powerful than diesel vehicles with the same displacement. Daimler-Benz AG responded to this with the OM 5, which in 1928 was the four-stroke diesel engine with the highest displacement on the German commercial vehicle market. Its output was rated at 71 hp (52 kW) at 1300 min -1 , the displacement is 8572 cm 3 . This development was possible because Bosch produced a new series injection pump in series from 1928 and the possibilities for calculating engines had improved. The engine reached a high for his time average working pressure of 5.6 bar. The engine was not up to this, which was expressed in "unmanageable difficulties" and in "reduced durability of the pistons". Theo Delfried Domina sees it as a thermal overuse of the engine. In the production model of the average operating pressure was therefore reduced to 4.74 bar. The rated power was thereby reduced from 71 hp to 60 hp at a speed of 1300 min -1 . Advances in diesel engine technology, the nominal speeds could soon be more than 2000 min -1be increased, whereby higher nominal powers were achieved. The OM 5 was replaced in 1932 by the OM 59 . The performance-enhanced OM 65 and OM 67 models are also based on this engine .