On April 12, 1997, at 1220 central daylight time, a Piper PA-24, N8739P, sustained substantial damage following a loss of engine power and a forced landing, near Elk Falls, Kansas. The private pilot and three passengers reported no injuries. The personal, 14 CFR Part 91 flight originated in Cherokee, Iowa, at 1008 with a planned destination of Mineola, Texas. Visual meteorological conditions prevailed and no flight plan was filed. The pilot said that he departed Cherokee, Iowa, with 30 gallons of fuel (full) in the left main tank. After flying for an unspecified time, the pilot said he switched "... fuel tanks from [the] left main to [the] right auxiliary tank." The pilot said that "... all readings and indications were normal (detent felt and quantity gauge read full)." The pilot said that at approximately 1215 cdt the engine lost power. The pilot said he selected alternate air heat, switched the electric fuel pump ON, selected the right main fuel tank with the fuel selector, and adjusted the throttle and mixture for an engine restart. The engine restart was unsuccessful. The pilot said he proceeded "... to the nearest airport at best rate of descent," and chose an off airport landing site on a gravel road. During the landing roll the pilot said the airplane impacted a fence line and trees. The pilot said that the aircraft had damage to both wings, bent propeller blades, broken lower cowl, and scratched and dented fuselage. The pilot also reported that the nose and left main gear separated and the right main gear was bent. Parts from the fuel selector were sent to the NTSB Office of Research and Engineering, Materials Laboratory for analysis. Details of the examination revealed that the fuel selector cam was separated from the shaft along the line of the braze joint. Brazing material was found on the surfaces of the shaft assembly and its respective hole. The O-ring separation contained features indicative of a brittle break, oriented on helical planes.