I was out skinig in my boat today with an 81 model Mecury 80 hp. we had been skiing for about 20 mins or so at an fairly slow rate..... guess 22 -25 mph... engine started to make an metalic hammering sound.....loud enough to be heard over engine...immediately shut down engine and looked at it......everything seemed in place.....restarted...had water out pisser.... and engine seemed close to normal.... but still noise....shut it down and towed back to trailer.....got home.....pulled all plugs...all 4 cylinder have 125 psi give or take 5 psi....feel this is normal......put muff on motor and restarted...noise isn't near as loud but still can faintly detect it......seems from high in power head or perhaps even under flywheel......will probably pull flywheel tommorow .....what could noise be....is it possible that wrist pin bad? wouldn't this make low compression?.....what about rod or main bearing.....if rod wouldn't it affect that cylinder....flywheel seems easy enough to turn......with plugs out.... seems bearing would affect this......don't want to teardown unnecessarily but don't want to ruin it either......where to from here...thanks guys
