On July 10, 1998, about 1912 eastern daylight time, a Cessna 180, N180DR, was substantially damaged during a forced landing while on approach to the Wadsworth Municipal Airport (3G3), Wadsworth, Ohio. The certificated private pilot and passenger were not injured. Visual meteorological conditions prevailed and an instrument flight rules flight plan had been filed for the flight that originated from Augusta (DNL), Georgia, at 1540. The personal flight was conducted under 14 CFR Part 91. According to the pilot, after an uneventful flight from DNL, he entered the traffic pattern at 3G3 for landing on runway 02. While on the downwind leg, about 800 feet above ground level, the airplane's engine suddenly lost power. The pilot said he followed the "engine out" procedures, which included switching the fuel selector position from the right tank to "both;" however, he was unable to restart the engine. The pilot further stated that the airplane was too low to allow for a runway landing and he elected to perform a forced landing to a grass field. The airplane came to rest about 300 feet south of the approach end of the runway. After the accident, during interviews with a Federal Aviation Administration (FFA) Inspector and a Ohio State Highway Patrol Officer, the pilot stated the engine lost power due to fuel exhaustion. He further said, the right fuel tank contained 15 gallons of fuel, but he "forgot to switch tanks." Examination of the wreckage by an FAA Inspector did not disclose any pre-impact malfunctions of the airframe or engine. When the carburetor drain plug was removed, approximately 1 cup of fuel was drained, which included about 1 teaspoon of water. Twenty gallons of fuel, an equal amount from each tank was drained from the airplane about 6 hours after the accident, after maintenance personnel noticed that fuel continued to leak from the gascolater, after the fuel selector had been placed in the "OFF" position.