Charles J. (Chuck) Haring, 73, the representative for a number of manufacturers of construction machinery and other heavy equipment, died of a heart attack Wednesday at Suburban Hospital in Bethesda. He was stricken at his office in Washington.

Mr. Haring was the founder and president of C.J. Haring Co. It served as factory representative of its clients with U. S. agencies and corporations here. It also represented its clients with foreign governments, corporations and international agencies.

A native of Elkhart, Ind., where he was an Eagle Scout, Mr. Haring was a graduate of Purdue University. He entered the heavy machinery Business in Indianapolis with the J. D. Adams Co., manufactuerers of road building equipment, and remained with the firm for 25 years. He was the general sales manager and a director at the time he left.

He moved to Pittsburgh in 1955 and founded his company there. He transferred it to Washington in 1958.

Mr. Haring was a member of the Agriculture and Construction Machinery Equipment Washington Representatives (ACME), the Construction Industry Manufacturers Association, the Associated Equipment Distributors and the Washington Export Council. He also was a member of the Road Builders and the Society of American Military Engineers. He was a member of the Congressional Country Club.

Survivors include his wife, Viola, of the home in Bethesda; a son, John Randolph, of Reston; a sister, Doratha Millican, of Dallas, and one grandson.

The family suggests that expressions of sympathy be in the form of contributions to the Montgomery County Heart Association. CAPTION: Picture, CHARLES J. HARING