Manufacturer: Otto Gas Engine Works, Philadelphia
Year: Circa 1929
Serial Number: 15737
This circa 1929 50 HP Otto Diesel engine was built in Philadelphia during the last days of the early and famous Otto Gas Engine Works. Also on display is the original air starting tank for the engine and a small Otto combination engine and air compressor that was used to pressurize the air starting tank.
This engine was reported to be the last, or at least nearly the last, engine to leave Otto when it closed in 1929. Prior to World War I, the Otto Gas Engine Works had German management. With the onset of hostilities with Germany, the federal government forced an asset transfer to American management. In 1929 the Otto Gas Engine Works factory was a division of the Superior Gas Engine Co. in Springfield, Ohio.
This engine closely follows the German design and employs the complete diesel principle, having no additional heat except compression to start ignition. It injects only enough fuel to keep its speed constant as controlled by the governor. For starting, it is rolled by compressed air. It’s somewhat European in appearance, with a single flywheel, sideshaft, over and under intake and exhaust valves, fuel injection pump and governor.
The Otto Diesel engine originally drove an ammonia compressor for refrigeration and a generator that made electricity in the Ice House, a block ice plant in Lewisburg, Pa. The plant made block ice primarily for residential use, when more people still had ice boxes rather than mechanical refrigerators. The local Amish demand kept it in service until 1955, when it was placed on standby.
Read more about this engine and 38 others in the new book, Coolspring, published by Gas Engine Magazine.