On December 18, 1997, at 2020 eastern standard time, a Piper PA-28R-200, N9418N, was destroyed during a forced landing and collision with trees near Skidmore, West Virginia. The certificated private pilot was seriously injured. Visual meteorological conditions prevailed for the business flight that originated at Charleston, West Virginia (CRW), at 1930, destined for Gaithersburg, Maryland (GAI). No flight plan was filed for the flight conducted under 14 CFR Part 91. The pilot stated he was in cruise flight at 7,500 feet with the engine producing 23 inches of manifold pressure at 2,400 RPM. He said the engine slowly and smoothly lost power over a 10-15 second duration. The engine completely lost power, but the propeller continued to windmill throughout the descent. The pilot said he adjusted to the best glide speed of 105 knots, turned on the fuel pump, and attempted a re-start in accordance with the checklist in the airplane. After several unsuccessful attempts to start the engine, the pilot transmitted a MAYDAY call that was relayed to CRW Departure Control by another aircraft. The pilot stated he was unable to select a forced landing area because the power loss occurred over an unlighted rural area. While in the final segment of the descent, the pilot said he "...had to dodge a couple of houses..." before the airplane struck trees and came to rest inverted. The pilot reported that the exhaust gas temperature gauge and the Distance Measuring Equipment display were inoperative. He said there were no other mechanical deficiencies with the airplane. Examination of the airplane's maintenance records revealed that overhaul of the engine was completed at the Textron-Lycoming engine factory on November 9, 1997. The engine was test run with all accessories installed prior to delivery to the owner. The engine was installed December 2, 1997, and logged 14.6 hours of flight time prior to the accident. The engine was examined at the Rostraver Airport, Belle Vernon, Pennsylvania, on February 18, 1998, under the supervision of a Federal Aviation Administration (FAA) Aviation Safety Inspector. The engine was rotated by hand and continuity was confirmed through the valvetrain and powertrain. Magneto to engine timing was confirmed and both magnetos produced spark at all terminal leads. Compression was verified using the thumb method. Evidence of fuel was found in the fuel bowl and in the lines to the fuel manifold. The fuel manifold was removed for further examination. The fuel manifold had been overhauled by its manufacturer, Precision Airmotive Corporation (PAM), Everett, Washington. The fuel manifold was examined on April 6, 1998, under the supervision of an FAA Aviation Safety inspector, at the Precision Airmotive Corporation facility. The "PAM" seal was in place prior to examination. According to the report submitted by Precision Airmotive: "When initially tested, the unit would not flow fuel. The brass plug was removed and the outer lock nut was found to have come off the stem. The nut was removed from the regulator, and a sample nut installed on the stem for the purposes of testing." In a telephone interview, the FAA Inspector who observed the examination and the flow tests stated: "On the initial flow test, it flowed like it was in idle cutoff all the time. When they took it apart, they found the outer nut in the diaphragm housing. They put a test nut on and it flowed perfectly." When questioned about the performance of the fuel servo and the engine with the outer nut no longer installed in the servo, the Inspector stated: "Basically, what it does is it shuts off the fuel when that nut backs off. It's just like pulling it to idle cut off."