Born in Kingston, Ontario, Dineen began his junior career with the WCJHL's Seattle Breakers before heading east to play with the OHA's Kingston Canadians. He was chosen 189th overall by the Philadelphia Flyers in 1980 then spent several years as a steady backliner in the AHL. In 1981 he helped the Maine Mariners reach the Calder Cup finals.
Dineen eventually signed as a free agent with the Kings and plated 11 games for them in 1986-87. He returned to the minors and was a solid worker on the Adirondack Red Wings of the AHL after he signed as a free agent with the Detroit Red Wings. Dineen played a couple of NHL games for the organization in 1989-90 but was sent back to the AHL. He retired in 1991 after suffering through an injury plagued season with the IHL's San Diego Gulls.
Courtesy of the Hockey Hall of Fame