Accident Overview
Shortly after departing from a local airport, the airplane sustained a total loss of engine power and subsequently crashed in a residential section. The pilot had recently purchased the aircraft. During a pre-buy inspection conducted at a facility in the Midwest, an oil filter check and oil analysis revealed the presence of metal particles. The broker advised the pilot not to fly the airplane until the engine was overhauled or exchanged. Instead, the pilot negotiated a price reduction, completed the purchase, and flew the airplane back to Northern California.
Pilot Actions Prior to Accident
After returning to Northern California, the pilot continued to operate the airplane, accruing 22.9 hours of flight time at the moment of the accident. No maintenance or engine overhaul had been performed prior to the flight.
Post-Accident Investigation
A post-accident engine examination disclosed that the crankshaft had failed in fatigue at the No. 2 journal, where it exits the No. 2 main bearing. Metallurgical examination revealed that the fatigue crack initiated due to improper torque of the thru-bolts. The airframe and engine had accrued a total of 937.4 hours since new. The engine had previously been overhauled at 522.5 hours due to a propeller strike.