Hello, first time on this forum. I have a 1975 Mercury 50 hp 2 cycle. Has the timing belt going to the distributor. We where out running it for about an hour and engine starting loosing power and knocking. We took covers off and ran it and noise seems to be coming from flywheel area or it is resonating through crank. I know this could be as bad as a broken crank or bearing, but is it possible the timing is off. Is it possible that the timing belt slipped a tooth, and would this cause knocking due to firing at the wrong time? I pulled flywheel off and arrow for distributor pulley was pointing approx. 2 teeth past the tdc mark on flywheel. Timing belt is VERY loose and probably has never been replaced(got the motor from somebody else). Also when I rotate the distributor pulley it makes a clicking noise. Belt is cheap and will probably try it, but thinking I have bigger problems. I checked and all cylinders are firing. I also noticed that there is a lot of fine aluminum millings underneath flywheel, but it doesn't look like stator was grinding on the flywheel? Thanks in advance for any advise.