On December 6, 1996, about 1100 eastern standard time, a Volmer VJ22 amphibious homebuilt airplane, N2921, registered to a private individual, crashed into a canal near Seminole, Florida. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 personal flight. The airplane was substantially damaged and the private-rated pilot, the sole occupant, was not injured. The flight originated about 30 minutes earlier from Lake Seminole, Seminole, Florida. The pilot stated that after takeoff from the lake he circled it four times and during a turn while adjusting the fuel/air ratio, the engine experienced a loss of power. He pushed the mixture control full rich, turned on the auxiliary fuel pump, applied full throttle and carburetor heat, but engine power was not restored. He initiated a descent for a forced landing on the lake but unable to clear a bridge ahead, he maneuvered the airplane for a forced landing on a canal. While descending, the right sponson collided with a tree. The airplane then descended into a canal and came to rest upright. The airplane was recovered and post crash, the engine was started and operated normally. Further examination of the airplane by the pilot/owner revealed blockage of the fuel tank outlet screen. The pilot/owner also stated that he had noticed in the past similar material in the gascolator screen. He further stated that the fuel tank had been out of the airplane 20 years and had been reinstalled in May of 1996. Fuel quantity was reportedly sufficient to sustain engine operation.