On December 6, 2020, about 1618 eastern daylight time, an Ercoupe 415-C, N2674H, was substantially damaged when it was involved in an accident near South Boston, Virginia. The private pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that the airplane had 25 gallons of fuel onboard when he departed on the accident flight. The pilot performed three takeoffs and landings, followed by a local sightseeing flight northeast of his home airport. About 45 minutes into the flight, the engine lost partial power. The pilot applied carburetor heat and used the primer to try and inject fuel into the engine; however, the engine eventually lost all power. The pilot subsequently performed a forced landing to a road, during which the airplane impacted a mailbox, resulting in substantial damage to the right wing. Following the accident, a mechanic examined the engine and noted that a fuel filter screen cover gasket from the fuel transfer pump that transferred fuel from the wings to the header fuel tank, had failed. The failed gasket would allow the fuel transfer pump to draw in air rather than fuel. The mechanic added that, when he replaced the failed gasket, the engine started normally, and the fuel transfer pump operated normally. Examination of the failed gasket by a Federal Aviation Administration inspector revealed that the gasket was damaged, possibly during installation. The inspector added that the gasket was an approved cork gasket. He further stated that the sight gauge for the fuel header tank was cloudy and an unapproved part. The failed gasket was installed on August 1, 2020, at the most recent annual inspection.