What happened
A private pilot was conducting a local area round-robin flight to various lakes to practice water landings under Title 14, CFR Part 91. While the aircraft was in cruise flight, the engine lost power. The pilot attempted to activate the boost pump, which caused the engine to produce power for several seconds before it quit completely. During the subsequent forced landing toward a small lake, the aircraft struck trees and landed short of the water. The wings of the aircraft sustained structural damage.
The investigation
During the investigation, a mechanic responsible for removing the wings for transport reported that no fuel was found in the wing fuel tanks. Another mechanic involved in the engine removal stated that the fuel system, including the gascolator, remained intact and showed no signs of leakage. This mechanic also noted that less than 1 gallon of fuel was removed from the aircraft's header tank, and a visual inspection of the engine compartment revealed no evidence of a fuel leak. The NTSB investigator-in-charge performed a visual examination of the exterior and found no evidence of fuel staining. However, in a written statement dated June 22, the pilot noted that his fuel consumption calculations indicated there should have been sufficient fuel for the flight, but he also observed fuel staining on the belly of the aircraft after recovery, which he believed indicated a leak from the gascolator.