CHI96LA262

The pilot reported that the number two cylinder and piston had just been replaced on the engine. He preflighted the aircraft, then did a twenty minute engine run-up. He then departed for a test flight around the airport. During the climb, the engine began to 'slow down,' so the pilot started a turn back to the airport. While he was in the turn, the engine seized. The pilot reported that due to lack of altitude, he was unable to reach a clear area, and he was forced to land in trees. Examination of the engine revealed that the number two piston had seized in the cylinder. The number 2 cylinder's bore was reported to be 0.007 inch over standard, and the piston was 0.015 inch oversize. The piston was galled as a result of the engine seizure. The cylinder and piston, which were used for repair, were used parts. The mechanic who had installed the parts reported that adequate clearances had existed.

On July 30, 1996, at 1921 central daylight time, a Piper PA-J3C, N3445K, was substantially damaged. The pilot was attempting to return to the airport for landing after he experienced engine failure after takeoff. The airplane hit a tree and remained lodged in its branches. The private pilot reported minor injuries. The 14 CFR Part 91 flight had departed the Camp Lake Airport, Camp Lake, Wisconsin, on a local flight. Visual meteorological conditions prevailed and no flight plan had been filed.

The pilot reported that the number two cylinder had just been replaced on the engine. The engine had not been run since it had been repaired. He reported that he preflighted the aircraft and then did an engine run-up. He reported that he was on the ground for 20 minutes with the engine running. He then departed for a test flight around the airport. He reported that during the climb the engine began to "slow down," so he started a turn back to the airport. While he was in the turn the engine quit. He reported that due to lack of altitude he was unable to land in any clear fields, and he did a forced landing in some trees.

The engine was examined and it was determined that the number two piston had seized in the cylinder. The number two cylinder's bore was a standard cylinder with .007 inch over standard. The number two piston, p/n 4557P15, a .015 inch oversized piston, was galled as a result of the engine seizure.

An Airworthiness Inspector from the Federal Aviation Administration reported that measurements and tolerances of the piston could not be determined due to the galling of the piston. He reported that the cylinder and piston used for repair were used parts. The inspector reported that the mechanic who had installed the parts reported that adequate clearances existed.