On June 19, 2001, about 2145 Alaska daylight time, a Piper PA-32-300 airplane, N43551, sustained substantial damage during a forced landing, about 6 miles east of Eek, Alaska. The airplane was being operated as a visual flight rules (VFR) cross-country positioning flight under Title 14, CFR Part 91, when the accident occurred. The airplane was operated by Poe Air, dba Kusko Aviation Inc., Bethel, Alaska. The commercial certificated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. VFR company flight following procedures were in effect. The flight originated at the Quinhagak Airport, Quinhagak, Alaska, about 2135. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on June 20, 2001, the pilot reported he was en route to Bethel after completing an air taxi charter flight. While in cruise flight about 500 feet above the ground, the pilot said the engine surged about three to four times. He said he activated the electric fuel boost pump, and switched fuel tanks, even though each fuel tank contained adequate fuel. The engine then quit, and the pilot said he selected an emergency landing area that was not completely covered by water. The airplane touched down in soft, marshy terrain and slid about 50 yards. The airplane received damage to the nose gear, the engine firewall, the left landing gear, the right landing gear, and the right wing. After the airplane was recovered, a Federal Aviation Administration (FAA) airworthiness inspector from the Anchorage Flight Standards District Office (FSDO), examined the airplane in Bethel on July 3, 2001. The inspector noted the engine had accrued about 500 hours since overhaul. During his examination of the engine, the inspector found that the airplane fuel tanks contained fuel. The electric fuel pump produced pressure. Opening of the throttle produced only a momentary increase in fuel pressure. After several attempts, the engine started and ran at an idle. The engine maintenance records indicated the engine driven fuel pump had been replaced twice since the overhaul. Each fuel pump installed on the engine by the operator since the engine overhaul was tested for proper operation. Each produced fuel pressure. The engine fuel servo was removed and tested for proper operation. During fuel flow testing, overseen by an NTSB investigator, the fuel servo produced a lean fuel mixture at a mid-range power setting. The servo, bearing the overhaul facilities coil loc lead seal, was disassembled after the flow check. The examination revealed the brass idle plug/main metering valve had part number 2541461 stamped on opposite sides of the vertical surface of the valve. One of the part numbers had been obliterated by a marking tool, and the number 2537665 etched on the valve with a hand marking tool. Part number 2537665 is the correct component for the model of servo. The valve appeared to a hand modified 2541461 which has a different metering jet placement than that of the correct 2537665 valve. The hand modification was produced by several punch tool indentations around the edges of the jet hole on both sides of the valve body. The indentations had hanging burrs protruding into the jet hole. The manual mixture control valve did not bear any part number.