List of Engine Manufacturers in USA:

Achates Power
Allison Engine Company
American Locomotive Company
Atlas-Imperial
Briggs & Stratton
Buda Engine Co.
Capstone Green Energy
Caterpillar Inc.
Continental Motors Company
Detroit Diesel
DMAX (engines)
Dresser-Rand
Electro-Motive Diesel
Elliott Company
Enterprise Engine and Foundry Co.
Evinrude Outboard Motors
Fairbanks-Morse
Foos Gas Engine Company
Gates Iron Works
GE Transportation
Gray Marine Motor Company
Hall-Scott
Hercules Engine Company
Hooven-Owens-Rentschler
Huber Manufacturing Co.
John Deere
Johnson Outboards
Sonny Leonard
Lycoming Engines
Mack Trucks
McIntosh & Seymour
Mercury Marine
NC2 Global
Nissan Marine
Nordberg Manufacturing Company
Offenhauser
Oldsmobile
Outboard Marine Corporation
Protean Electric
Rutenber Motor Company
Samuel F. Hodge & Company
S&S Cycle
Sintz Gas Engine Company
Solar Turbines
Stover Manufacturing and Engine Company
Tecumseh Products
Toyota Motor Manufacturing Alabama
Union Iron Works
UQM Technologies
Vericor Power Systems
Waukesha Engine
Weidely Motors Company
West Bend Company
Westinghouse Electric Corporation
White and Middleton
Wisconsin Motor Manufacturing Company