My 1992 200hp Yamaha 2 stroke was running fine at 3/4 throttle when it suddenly made a bad noise and shut down. After towing it in and getting it home I checked compression all cyls. were fine except one. All were 120 and the one was 70, it sounded like it broke a rod when this happened but after doing the test it appears something else has happened. The engine will start that was tried for about 5 seconds but something has definitly gone wrong. The only thing I can figure is a rod bolt snapped and or stretched only pulling down that piston part way and then pushing it up all the way? Any ideas? I have not started tearing down the engine yet, was tryying to get some info first. thanks