The airplane was substantially damaged when it struck a fence and terrain during a forced landing at approximately 1810 Mountain time. Visual conditions prevailed; the pilot, pilot-rated passenger and three other passengers aboard were not injured. The flight originated from Bullfrog Basin, Utah, at approximately 1630. The pilot later stated the airplane was in level cruise flight at 13,500 feet msl when the engine began chugging and started losing power. All attempts to restore power were to no avail. When he turned final for the runway at Salida, he lost visual contact with the runway from the suns glare. The pilot selected a field and touched down mile off runway centerline and 1 mile short of the runway.