What happened
The pilot experienced a loss of engine power while conducting a test flight following the replacement of two cylinders on the aircraft engine. During the event, the pilot attempted an emergency approach to an airstrip and was nearly on the runway when the engine restarted. The pilot elected to perform a go-around rather than landing at that location, intending to fly to his private rural airstrip. Shortly after departing the airstrip, the engine failed again, resulting in a forced landing in a gravel pit.
The pilot reported that although the engine had quit, one of the fuel tanks still contained fuel. The pilot was not injured during the incident.
Findings
Investigation into the circumstances revealed that the pilot was a noncertificated pilot and not an aviation mechanic. There was no indication that the aircraft had received any required inspections prior to the flight. The pilot noted that he routinely operates the aircraft from his own private airstrip.