Hooven-Owens-Rentschler

The firm of Hooven, Owens, Rentschler, and Company manufactured steam and diesel engines in Hamilton, Ohio. Because the firm was frequently known by its initials, H.O.R., the Hooven is sometimes incorrectly rendered as Hoover, and the Owens may be mistaken for Owen.

The firm was the successor to the firm of Owens, Ebert & Dyer (founded in 1845 by Job E. Owens) which went into receivership in 1876.

In 1882, George A. Rentschler, J. C. Hooven, Henry C. Sohn, George H. Helvey, and James E. Campbell merged the firm with the iron works of Sohn and Rentschler, and adopted the name Hooven, Owens, Rentschler Co.

In 1883 the firm began the manufacture of Corliss steam engines, producing a total of 700 such engines by 1901.

By World War I, the Hooven-Owens-Rentschler Company operated the largest exclusive Corliss Engine plant in the country, employing nearly 800 men.

In 1928 the company merged with the Niles Tool Works to form the General Machinery Corporation. However, it continued to make diesel engines under the H.O.R. brand, and supplied many of the powerplants for United States submarines and liberty ships during World War II. General Machinery Corporation ranked 91st among United States corporations in the value of World War II military production contracts.

In the 1930s H.O.R. developed a double-acting two-stroke diesel engine, initially based on the German cruiser Leipzig's MAN engines but with eight cylinders instead of seven, expanded to nine cylinders in the final submarine version. The double-acting design produced more power from a physically smaller engine than conventional designs. However, H.O.R.'s double-acting engines, particularly those of USS Pompano, gained notoriety for their unreliability in the submarine force, where they were nicknamed "whores." During World War II, all submarine H.O.R. engines were replaced by early 1943, usually with General Motors Cleveland Division engines or Fairbanks-Morse Model 38 engines.

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