The Mercedes D. II was a 6-cylinder, liquid cooled inline aircraft engine built by Daimler during the early stages of World War I. An aircraft engine is a Propulsion system for an Aircraft. Aircraft engines are almost always a type of lightweight Internal combustion engine. Daimler-Motoren-Gesellschaft ( Daimler Motor Company, DMG was a German Engine and later Automobile manufacturer in operation from 1890 World War I (abbreviated WWI; also known as the First World War, the Great War, and the War to End All Producing about 110 to 120 hp, it was at the low-end of the power range of contemporary engines, and was generally outperformed by rotaries who's power-to-weight ratio tended to be much better. Power-to-weight ratio (specific power is a calculation commonly applied to Engines and other mobile power sources to enable the comparison of one unit or design to another It also had stiff competition from the Ferdinand Porsche-designed 120 hp Austro-Daimler 6. Prof Dr Ing hc Ferdinand Porsche ( The Austro-Daimler 6 was a 6 cylinder Liquid-cooled inline engine first produced in 1910 The D. II was produced only briefly as a result, but its design formed the basis for the later Mercedes D.III which saw widespread use throughout the war. The Mercedes DIII, or F1466 as it was known internally was a 6-cylinder liquid cooled inline Aircraft engine built by Daimler and used on a wide variety
The D. II was based on the Austro-Daimler to a large degree. Like the Austro-Daimler, it was built up from the crankcase, which was milled from two pieces of cast aluminum bolted together at their midline. For the GI Joe character see List of GI Joe ARAH characters. For the Transformers characters see Crankcase (Transformers. The cylinders were separately milled from steel and bolted to the top of the crankcase. Steel sleeves were fitted over the cylinders and welded on to form a cooling jacket. Much of this complexity is due to the differential rates of expansion of steel and aluminum, which precluded screwing the cylinders into the crankcase, and the alloys of the era meant that an aluminum cylinder was not possible. Both engines also used a scavenger pump to pump oil out of the crankcase to a separate cylinder, where a second high-pressure pump supplied oil to the engine. This arrangement allowed for a much smaller "sump" on the bottom of the crankcase, reducing the overall size of the engine, although in the case of the D. II it was not nearly as much as the Austro-Daimler.
Where the D. II differed from the Austro-Daimler was largely in mechanical arrangement. For instance, the D. II featured a single overhead cam, powered by a shaft leading up from the crankshaft at the rear of the engine, whereas the Austro-Daimler had a more "conventional" system using pushrods driven off the crank. Overhead camshaft, commonly abbreviated to OHC, Valvetrain configurations place the engine Camshaft within the Cylinder heads above the The crankshaft, sometimes casually abbreviated to crank, is the part of an Engine which translates reciprocating Linear Another unique feature was the ability to shift the camshaft to a "half compression" position for starting. Additionally, the D. II used two carburetors located together on one side of the engine, feeding the cylinders through two pipes; the Austro-Daimler separated their carburetors to locate them closer to the cylinders they fed. The D. II also used a unique cooling jacket design, with every two cylinders being covered by a single jacket.
The D. II was fairly quickly replaced by the D. III, and ended production around 1916. The D. III was essentially a scaled-up D. II, although it abandoned the paired cooling jackets.
One known surviving example of this engine is at Old Rhinebeck Aerodrome-its crankshaft may not be whole, however.