The company began operations in the early 1900’s as a small machine shop. It began to manufacture single cylinder engines primarily for farm use for pumping water, sawing wood, and jobs such as these in 1907, in 1909, it was incorporated into Fairmont Machine Company. That year marked the first time that Fairmont engines were applied to railway hand or pump cars and thereby provided their entrance into the rail industry. 

The company name was changed to Fairmont Gas Engine and Railway Motor Car Company in 1915. Soon the company began the design and development of complete motor cars and began producing their own models in the early 1920’s. In addition, during that same decade, the company began to produce and sell permanent way equipment that included weed burners, weed mowers, and ballast dicers.

In 1923, the firm adopted the name, Fairmont Railway Motors, Inc. The 1920’s saw further expansion that included an international flavour. This involved the purchase of Mudge and Company of Chicago, a railway motor car business, in 1928, and the formation of a Canadian subsidiary in 1929, Fairmont Railway Motors, Ltd., which was located in suburban Toronto.

The late 1940’s saw the development of Road-Rail vehicles that could also be applied to operate on passenger cars, pickup trucks, or large rail cranes. The early 1960’s saw the introduction of a line of lightweight hydraulic hand tools and eventually a hydraulic motor. These were used mainly for electrical transmission line construction as well as maintenance and tree trimming. This resulted in a new division called Fairmont Hydraulics.

Stockholders approved a merger with Harsco, a diversified enterprise located in Harrisburg, Pennsylvania, on June 8, 1979.