What happened
While flying at an altitude of 3500 feet, the aircraft's engine lost power. The pilot attempted to restart the engine, but these efforts were unsuccessful. Consequently, the pilot performed a forced landing in a plowed field. During the landing, the nose gear collapsed, resulting in damage to the aircraft.
The investigation
Investigators removed the carburetor for an internal examination. This inspection revealed that the clearance between the float and the bowl was less than the required specification due to wear on the float shaft bracket. Because of this condition, an excessive float drop—measured between 1.58 and 1.8 inches—was necessary to initiate the opening of the needle valve and allow fuel into the chamber. Additionally, it was discovered that the float chafed against the wall of the carburetor bowl before the needle valve could open. No other mechanical issues were identified during the examination.