Accident Overview
The aircraft owner, who holds an Airframe and Powerplant (A&P) mechanic certificate, had complied with an Airworthiness Directive (AD) requiring replacement of the oil cooler hose. After completing the work, he ran the engine at idle but did not remove the engine cowling to inspect for oil leaks.
Pre-takeoff Observations
The airport manager reported seeing a large oil puddle at the location where the airplane was started, as well as a trail of oil leading to the runway.
Flight and Forced Landing
The airplane climbed to approximately 250 feet above ground level when the engine lost power. The pilot executed a forced landing.
Engine Examination
A teardown inspection of the engine revealed no oil present. Bearings and journals showed evidence of heat distress. The number 2 connecting rod had separated from the crankshaft. One oil cooler line was found loose, requiring an 180-degree turn of the nut to achieve proper tightening.