On May 20, 2021, about 0930 eastern daylight time, a Mooney M20K, N9514R, was substantially damaged when it was involved in an accident near Dawson Municipal Airport (16J), Dawson, Georgia. The pilot and passenger sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, he had recently purchased the airplane. On the day of the accident, the pilot conducted a preflight inspection with no anomalies noted, and the airplane departed Orlando Apopka Airport (X04), Apopka, Florida, about 0815 for a flight to Birmingham-Shuttlesworth International Airport (BHM), Birmingham, Alabama. While en route to the destination airport, the airplane lost total engine power. The pilot declared an emergency to air traffic control and diverted to the nearest airport, which was 16J. During the descent, the pilot operated the engine controls with no response from the engine. The pilot realized that the airplane would not reach the airport, and he landed the airplane on a road with the landing gear and flaps retracted. The airplane’s right wing and fuselage were substantially damaged. A postaccident teardown examination revealed two holes in the top of the engine crankcase, with the larger hole near the center and the smaller hole just aft. The cylinders remained attached to the crankcase. The No. 4 connecting rod was found fractured about midspan. A No. 4 connecting rod bolt nut was found in the oil pan. This nut exhibited no signs of impact damage or damage that would be consistent with separation. A cotter pin associated with the nut was not located. The other No. 4 connecting rod nut was found secured to its bolt with the cotter pin installed. All other connecting rod bolt nuts remained attached to their respective bolts with cotter pins in place. The oil filter pleats and oil sump contained a large amount of metallic debris. Review of maintenance records revealed that the engine had accumulated about 1,240 hours of operation since its last major overhaul, which was completed on September 18, 1992. The engine manufacturer recommended that the engine be overhauled every 2,000 hours or 12 calendar years, whichever occurred first. Further review of the records revealed that the engine was disassembled, cleaned, and inspected due to a crankcase crack in 2005 and that the No. 3 cylinder was replaced in 2013.