On October 4, 2006, at 1815 central daylight time, a Grumman G-164, N493Y, registered to and operated by Fayette Flying Service LLC, as a 14 Code of Federal Regulation Part 137 aerial application flight, loss full engine power while maneuvering in the vicinity of Somerville, Tennessee. The airplane collided with a tree while making a force landing, and was substantially damaged by post-crash fire. Visual meteorological conditions prevailed and no flight plan was filed. The private pilot received minor injuries. The flight originated from the Fayette County Airport, Somerville, Tennessee, at 1750. The pilot reported that he was conducting an aerial application flight. He stated that about half way through the third turn-around maneuver a gradual loss of power occurred. He added full throttle but did not notice the difference in the engine sound or the power output. He made a forced landing into a small field of trees and the airplane collided with the ground. Examination of the airplane by an FAA inspector revealed that all components for flight were located at the crash site. An examination of the engine revealed that all of its components were heavily fire damaged, and an engine examination could not be facilitated due to the fire damage. A review of the engine logbook pages revealed that the engine was overhauled on July 27, 2006 at an engine total time of 524.7 hours. After the engine was reinstalled it was run for 1-hour. The owner of the airplane did not submit the airplane logbooks or records for review to the NTSB.