The aircraft nose gear collapsed during a forced landing after the engine quit. Neither the aircraft owner nor the aircraft had flown for over 9 months. The owner was on a recheck flight with a CFI for currency. The owner had preflighted the aircraft and found no water in the fuel sumps. The CFI did not participate in the preflight or even witness it but accepted the owner's assessment since he had seen the owner preflight on a prior occasion. The flight proceeded normally until the CFI made some steep turns. The engine failed to respond to throttle a short while after the turns while the owner was flying. The CFI took over for the emergency and failed to get a restart, so a forced landing was made. Post-accident investigation revealed water in the fuel lines and carburetor. One cup of water was drained from the gascolator. The aircraft has two 18-gallon fuel tanks situated in the wings, level enough so that water could collect over the entire bottom without collecting at the fuel outlet lines.