Incident Overview
A private pilot reported that shortly after takeoff from an airport, the airplane's engine lost power. The engine momentarily regained power but then quit again, repeating this cycle 15 to 17 times. The pilot then elected to make an off-airport landing in a nearby field. During the landing rollout, the airplane collided with a fence and a drainage ditch, resulting in substantial damage.
Post-Accident Examination
Following the accident, maintenance personnel from Aviation Inspection and Repair, Inc. examined the aircraft. They found that the gascolator gasket installed on the accident airplane was the incorrect size. The gasket measured 1-3/8 inches inside diameter by 1-15/16 inches outside diameter. According to Piper Aircraft, the manufacturer, the proper gascolator gasket (part number 462-049) measures 1-7/8 by 2-3/16 inches respectively.
Cause of Power Loss
Maintenance personnel reported that the undersized gasket allowed the passage of air into the closed fuel system, resulting in irregular fuel pressure to the engine. This irregular fuel pressure is consistent with the repeated engine power loss incidents described by the pilot.