Mercedes-Benz OM 636

from Wikipedia, the free encyclopedia
Daimler Benz
OM 636

OM 636
OM 636
Production period: 1949-1990
Manufacturer: Daimler Benz
Working principle: diesel
Motor design: line
Valve control: OHV valve control
Displacement: 1697-1767 cm 3
Mixture preparation: Pre-chamber injection
Engine charging: no
Power: 18-32 kW
Torque: 96-101 Nm
Previous model: OM 138
Successor: OM 621

The OM 636 is a four-stroke - antechamber - diesel engine with four cylinders in series developed and produced by Daimler-Benz . It was introduced in 1949. The successor was the OM 621 .

These engines have been installed in passenger cars, vans and small trucks of the Mercedes-Benz brand since the late 1940s. Other manufacturers also built this engine into their vehicles. The abbreviation "OM" stands for "Oel-Motor", ie an engine that is operated with light oil / diesel, and still refers to Daimler's diesel engines to this day .

history

During the Second World War, under the direction of Fritz Nallinger, Daimler-Benz developed a successor to the OM 138 , which was to be used as an engine in the Mercedes-Benz 170 D of the W 136 series. The engine was ready for series production by 1948 at the latest, but was not yet installed in the car. Instead, the Boehringer company tested the engine with the 636.912 model for Daimler-Benz and installed it in the Unimog of the 70.200 series, which was still manufactured by Boehringer at the time . This engine has a bore of only 73.5 mm and therefore only 1697 cm 3 displacement, furthermore it has a split valve cover. The output is 25 hp (18.5 kW) at 2300 rpm.

The series engines later manufactured by Daimler-Benz had a bore that was enlarged to 75 mm and a displacement of 1767 cm 3 .

After 1961, with the appearance of the successor model W 110 , the OM 636 was no longer used in Mercedes-Benz cars. It was replaced by the OM 621 .

In addition, the OM 636 was installed in a large number of other vehicles; Starting with the drive for the Unimog and in the first versions of the Mercedes-Benz L 319 light truck and the Mercedes-Benz O 319 minibus, the engine was also used in forklifts , as a built-in engine in ships and to drive power units , fire pumps and many other things. Also in cars of the type OM engines were installed 636 includes: Seat in Spain equipped by the Fiat 124 derived taxi models until the late 1980s optional with this Mercedes engine off.

For example, since the engine was no longer installed in cars, production has only taken place in Spain at MEVOSA. As a built-in engine, e.g. B. for forklifts, the engine type was in the price lists of Daimler-Benz until the 1990s.

technology

View from diagonally above.

The engine is water-cooled and has a thermostat with a short-circuit line. The engine block and cylinder head are made of gray cast iron , the OM 636.912 and OM 636.915 have two valve covers, all other models only have one continuous valve cover. The triple-bearing crankshaft and the connecting rods are forged from steel. The pistons are each cast forged to model or and made of light metal. The engine has overhead valves (2 per cylinder) and an underlying camshaft ( OHV ) driven by a pair of gears . The Bosch in-line injection pump is driven by the camshaft via another pair of gears. The fuel is injected into antechamber . The inlet and the antechambers are on the left, the outlet, camshaft and injection pump are on the right. Model 636.914 does not have an injection adjuster and is throttled above the final speed, whereas model 636.930 has an injection adjuster. As with the OM 138 , the cooling water pump is built into the cylinder head and is driven by a belt from the crankshaft.

The weak point of the engine is the thermal overload of the cylinder head, as the web between the valves is too narrow and the heat cannot be dissipated. This can lead to hairline cracks and ultimately water ingress into the combustion chamber.

Model vehicle Bore × stroke
[mm]		 Cubic capacity
[cm 3 ]		 compression Power [kW (PS)]
at speed [1 / min]		 Torque [Nm]
at speed [1 / min]		 Maximum speed [1 / min]
636.912 Boehringer Unimog 70.200 73.5 x 100 mm 1697 cm 3 18.5 (25) at 2300
636.914 Unimog 2010 , 401, 402 , 411 75 × 100 mm 1767 cm 3 depending on the version between:
22 (30) for 2300
to
26.5 (36) for 2750
636.915 170 D 73.5 x 100 mm 1697 cm 3 19: 1 28 (38) at 3200 96 at 2000
636.919 L 319 D , L 406 D 75 × 100 mm 1767 cm 3
636. ??? 170 DS 29.5 (40) at 3200 101 at 2000
636.930 180 D 19: 1 31.5 (43) at 3500 98 at 1500 3600

Further use of the OM 636

the OM 636 as a drive motor for a cabin boat

Individual evidence

  1. ↑ Vogler, p. 49
  2. ↑ F. Sass, Ch. Bouché, A Leitner (ed.): Dubbels Taschenbuch für den Maschinenbau , 12th edition, Springer, Berlin / Heidelberg, 1963. ISBN 978-3-662-41645-7 . P. 177

literature

Web links

Commons : Mercedes-Benz OM 636  - Collection of pictures, videos and audio files