Preflight Inspection
The pilot performed a preflight inspection of the airplane and observed water in the fuel system. The pilot drained the fuel system and allowed the engine to operate for "well over 15 minutes" prior to takeoff. The airplane departed uneventfully.
Loss of Engine Power
Later in the flight, while maneuvering, the airplane experienced a total loss of engine power. The pilot was unable to restart the engine and performed a forced landing to a marsh area.
Post-Accident Examination
Examination of the airplane and engine included draining fuel samples from both wing fuel tanks, the gascolator, and the carburetor. These samples revealed significant amounts of water contamination throughout the airplane's fuel system.
The undersides of both the right and left wing fuel caps exhibited evidence of corrosion. The right wing fuel cap seal was severely worn and cracked.
Contributing Conditions
The airplane was parked outside for over a week. Weather observations reported for the area during the two-week period prior to the accident included several observations of precipitation. The airplane had been operated for about 15 hours since its most recent annual inspection, which was performed about two months prior to the accident.