On December 20, 1997, at 1015 hours Pacific standard time, a Bellanca 8KCAB, N5058L, was substantially damaged when it nosed over during a forced landing on a snow covered field 3 statute miles northeast of Truckee, California. The solo commercial pilot was not injured. The pilot stated that the engine started to run rough during the climb and then stopped suddenly with the propeller in a horizontal position. Several restart attempts were unsuccessful. The flight departed the Truckee-Tahoe Airport on a personal flight to Smith Ranch, Marinwood, California, and no flight plan was filed. Visual meteorological conditions prevailed at the time. The Federal Aviation Administration (FAA) inspector who investigated the accident site stated that he observed a considerable amount of engine oil on the underside of the engine, the belly of the aircraft, and the engine compartment firewall. He also stated that after righting the aircraft it was noted that the engine could not be rotated in either direction due to an apparent internal mechanical restriction. A teardown inspection of the engine was performed at the owner's maintenance base. The FAA inspectors who witnessed the inspection reported that the number 3 rod assembly had experienced a progressive failure. (See attached FAA Report of Engine Inspection.)