Incident
Approximately 39 minutes after departure, the airplane experienced a loss of engine power. The pilot executed a forced landing on a golf course. During the landing, the nose gear collapsed, causing the airplane to nosed over.
Maintenance History
Prior to the accident, maintenance had been performed on the airplane by an uncertificated person, constituting unapproved maintenance. During this work, the engine kicked back upon starting, resulting in a broken gear on the starter drive. A magnet was used to retrieve the broken gear from the rear of the engine. However, the accessory case was not removed to recover the remaining broken gear particles.
Post-Accident Inspection
A post-accident examination of the engine revealed that both magneto shafts had been sheared. The shearing was caused by a foreign object that had become trapped between the right magneto gear and the accessory case. The foreign object was consistent with debris from the previously broken starter drive gear that had not been fully recovered during the unapproved maintenance.