On August 23, 2003, about 1245 central daylight time, a Cessna 150J, N61134, piloted by a private pilot, sustained substantial damage when the airplane nosed over during a forced landing following an in-flight loss of engine power near Fennimore, Wisconsin. The personal flight was operating under 14 CFR Part 91. Visual meteorological conditions prevailed at the time of the accident. No flight plan was on file. The pilot and passenger sustained minor injuries. The flight originated about 1057 from the Kenosha Regional Airport (ENW), near Kenosha, Wisconsin, and was destined for the Prairie du Chien Municipal Airport, near Prairie du Chien, Wisconsin, at the time of the accident. The pilot reported that he departed from ENW with "16 -18" gallons of fuel on board. The pilot stated: [I] left Kenosha, Wisconsin, at 10:57 a.m. headed west toward the Mississippi River, Prairie du Chien. Engine quit over wooded/hilly mixed farmland. [I] went through emergency procedures then picked a field to land. [I] did not make it to the desired field. The engine was shipped to Teledyne Continental Motors in Mobile, Alabama, for a test run under the oversight of a Federal Aviation Administration Inspector. The engine's carburetor sustained impact damage and was found to have broken mounting ears. The engine was run with a slave carburetor and produced rated power. The original carburetor mount was repaired with a bonding material. The engine produced rated power with the original carburetor. The results of this test run are appended to the docket material associated with this case. The Cessna 150 manual's cruise performance chart showed a fuel burn of 7.2 gallons per hour at an altitude of 2,500 feet and a 2,750 RPM setting. The cruise performance chart is appended to the docket material associated with this case. At 1153, the Boscobel Airport (OVS) recorded weather was: wind 360 degrees at 03 knots; visibility 10 statute miles; sky condition clear; temperature 29 degrees C; dew point 14 degrees C; altimeter 30.20 inches of mercury. At 1253, the recorded OVS weather was: wind variable at 04 knots; visibility 10 statute miles; sky condition clear; temperature 29 degrees C; dew point 12 degrees C; altimeter 30.18 inches of mercury. A carburetor icing chart, copied from a Transport Canada source, was reviewed. The temperature of 29 degrees C and dew point of 12 degrees C were applied to the chart. The intersection of those temperatures was in the "light icing - cruise or descent power" portion of the chart. The carburetor icing chart is appended to the docket material associated with this case.