On July 9, 1998, at 1300 eastern daylight time, a homebuilt Rans S12, N6191V, was substantially damaged when it collided with terrain during a forced landing near Phillips, Maine. The certificated student pilot and passenger were seriously injured. Visual meteorological conditions prevailed and a flight plan was not filed. The local, personal flight, was conducted under 14 CFR Part 91, and originated at a private grass strip in Phillips, Maine. The student pilot reported that he was cruising at 400 feet AGL, photographing fields, when the engine initially quit. He performed the emergency procedures for a loss of engine power, the engine restarted, and he tried to climb, but the engine quit a second time. A forced landing was then performed to a hay field. The wreckage was examined by an FAA Inspector. The examination revealed the linkage that connected the oil feed line to the uncertificated two cycle engine had separated. The student pilot reported 40 hours of total flight experience including four hours in make and model.