On September 7, 2002, about 0910 eastern daylight time, a homebuilt Seawind 3000, N278ER, was substantially damaged during a forced landing near Bloomingburg, Ohio. The certificated private pilot was seriously injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight conducted under 14 CFR Part 91. According to the pilot, he had been experiencing high engine oil temperatures on previous flights, and was attempting to determine the cause. After departing the Fayette County Airport (I23), Washington Court House, Ohio, the oil temperature began to rise, and the pilot elected to return to the airport. While proceeding to the airport, the pilot decided to open the cowl flaps to see if the temperature would decrease, but mistakenly, pulled the fuel shutoff lever. The engine lost total power, and after unsuccessful attempts to restart the engine, the pilot initiated a forced landing to a grass field. Unable to make the grass field, the pilot touched down in a cornfield, struck low-lying utility lines, and nosed over, coming to rest inverted.