Fairbanks-Morse 38D8-1/8

Fairbanks-Morse 38D8-1/8
Name	Fairbanks-Morse 38D8-1/8
Powertype	Diesel
Builder	Fairbanks-Morse
Builddate	1937–1955
Primemover	opposed-piston diesel
Aspiration	Roots blower / turbocharged (varies)
Displacement	8.125 in bore (per cylinder)
Cylcount	8, 10, 12 (model dependent)
Locale	United States, Canada, export markets

Fairbanks-Morse 38D8-1/8 is an opposed-piston, two-stroke diesel engine design produced by Fairbanks-Morse that powered locomotives, maritime vessels, and stationary installations from the late 1930s through the mid-20th century. The design is notable for its compact opposed-piston architecture derived from preceding Fairbanks-Morse H-24 and Fairbanks-Morse 38D8-1/8 series developments, and for service aboard United States Navy submarines and in North American railroad motive power. The engine intersected with industrial trends exemplified by Electro-Motive Corporation, General Motors, and Baldwin Locomotive Works in the dieselization of railroads and naval propulsion.

Design and Specifications

The 38D8-1/8 is characterized by opposed pistons in a single cylinder block, eliminating cylinder heads in a layout influenced by earlier Junkers Jumo 205 and Fairbanks-Morse MAN collaborations, with a bore of 8+1/8 inches and varying stroke lengths tied to model variants. Key components included forged crankshafts, crosshead assemblies comparable to designs used by Winton Engine Corporation, and a Roots-type blower or turbocharger sourced from suppliers like Holset or BorgWarner depending on application. Engine control systems interfaced with generators and traction motors supplied by manufacturers such as Westinghouse Electric Corporation, General Electric, and Allis-Chalmers. Materials and metallurgy reflected practices seen at industrial firms including Carpenter Technology and Allegheny Ludlum, while lubrication and filtration paralleled equipment from Shell Oil Company and ExxonMobil service branches.

Development and Production

Development of the 38D8-1/8 lineage was driven by Fairbanks-Morse efforts to produce a compact, high-power diesel for both marine and railroad markets during the interwar and wartime periods, intersecting with procurement programs from the United States Navy and railroads such as the New York Central Railroad and the Pennsylvania Railroad. Production facilities at the Fairbanks-Morse plant in Cleveland, Ohio and subcontracting arrangements with firms like Alco and General Machinery Corporation expanded manufacturing capacity. Wartime demand linked the engine to contracts from the United States Maritime Commission and programs overseen by the War Production Board, with postwar civilian orders influenced by dieselization campaigns led by carriers including Atchison, Topeka and Santa Fe Railway and Southern Pacific Transportation Company.

Variants and Modifications

Variants encompassed different cylinder counts and power ratings for applications from submarine propulsion in Gato-class submarine conversions to road-switcher locomotives deployed by Class I railroads. Modifications included turbocharging retrofits similar to aftermarket programs from United Aircraft subsidiaries, cold-weather kits adopted by operators in Canada and Alaska Railroad, and marine adaptations complying with standards of the American Bureau of Shipping and the United States Coast Guard. Experimental conversions paralleled work conducted by American Locomotive Company and trials performed by National Railway Equipment Company, and field upgrades often used components from Caterpillar Inc. and Cummins for auxiliary systems.

Applications and Operators

The 38D8-1/8 family served in multiple domains: main propulsion aboard United States Navy submarines and auxiliary power on Liberty ship conversions; prime movers in diesel-electric locomotives used by New Haven Railroad, Baltimore and Ohio Railroad, and regional carriers; and stationary generators for industrial customers including U.S. Steel facilities and Tennant Company plants. International operators included navies and railways in Canada, United Kingdom, Australia, and Argentina, with installations maintained under contracts from companies like Siemens and ABB for electrical systems.

Performance and Reliability

Performance metrics varied by installation: specific power, torque curves, and fuel consumption were influenced by supercharging, intercooling, and maintenance regimes overseen by workshops analogous to those at Northrop Grumman shipyards and railroad shops such as Hyde Park Shops. The opposed-piston design conferred advantages in thermal efficiency noted in contemporary engineering assessments by institutions like Society of Automotive Engineers and American Society of Mechanical Engineers, while reliability histories showed sensitivity to lubrication quality, air scavenging, and saltwater corrosion in naval use—issues addressed through overhaul cycles at facilities like Philadelphia Naval Shipyard and Puget Sound Naval Shipyard.

Preservation and Surviving Examples

Surviving 38D8-1/8 engines and installations are preserved by museums and heritage organizations including the National Museum of the United States Navy, the Illinois Railway Museum, and local maritime museums in Newport News, Virginia and San Francisco. Restoration projects often collaborate with volunteer groups and contractors linked to Steam Railroading Institute, Railway Preservation Society of Ireland affiliates, and university engineering departments at Massachusetts Institute of Technology and University of Michigan for materials analysis and reconditioning. Several restored locomotives and marine exhibits operate at heritage events organized by institutions such as Smithsonian Institution affiliates and regional historical societies.

Category:Diesel locomotive engines Category:Fairbanks-Morse