On August 6, 2000, approximately 1700 mountain daylight time, a Piper PA-22-108 (converted to a PA-20), N4689Z, was substantially damaged when it nosed over during a forced landing at Starvation Reservoir, near Duchesne, Utah. The airline transport certificated pilot, the sole occupant aboard, was not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the personal flight being conducted under Title 14 CFR Part 91. The flight originated at Duchesne minutes before the accident. The following is based on the pilot's accident report and information he supplied during a telephone conversation. He departed Duchesne Municipal Airport, and was en route to Salt Lake City Municipal 2 Airport. After leaving the aircraft traffic pattern, he switched the fuel selector from the left tank to the right tank and within a few moments the engine lost power. He switched the fuel selector back to the left tank, but could not restart the engine. He made a forced landing on a beach at Starvation Reservoir at an approach speed that was a "little fast." When he applied brakes, the airplane nosed over. A witness at the scene stated that the pilot said, "I may have shut the fuel off." The pilot later said the fuel selector handle and indicator pointer were not aligned with each other. According to the Piper Aircraft Corporation, the fuel selector valve handle and pointer are both installed on the fuel selector valve shaft via a key-way, and that both must reference the same detent for positive engagement in all four detent positions. As a result, FAA issued Airworthiness Directive (A.D.) 60-10-08, effective May 13, 1960, requiring the inspection of the fuel selector valve to assure proper alignment of the handle and pointer. The A.D. is repetitive every 100 hours time-in-service. According to the airplane maintenance records, all airworthiness directives, including A.D. 60-10-08, were in compliance. An FAA airworthiness inspector from the Salt Lake City Flight Standards District Office examined the airplane and found that the fuel selector operated correctly. Both wing ribs, left engine mount, left strut, vertical stabilizer and rudder were damaged.