Junkers L2

The Junkers L2 was the company's first water-cooled four-stroke engine and the first of its engines to be built on a production line, although only 58 were made. It was a six-cylinder upright inline engine with direct drive and four overhead-camshaft-driven valves per cylinder, sharing many features with the earlier air-cooled L1 but with a much greater swept volume of 19.1 litres. The letter L in the name marks a four-stroke petrol engine, as opposed to a two-stroke diesel. It initially developed a cruise power of 195 horsepower at 1,550 rpm, later raised to 220 horsepower. It powered early versions of several Junkers aircraft, including the F 13, G 24 and W 33, until it was replaced by the more powerful L5.