I have A 1992 MERCRUISER 4.3 . I had been getting a little water in the oil for the last year or so. I figured the block was cracked so i was riding it out for as long as i could. I fianlly decided to pull the intake manifold and heads and take a look. Found the intake manifold gasket was destroyed. so i replaced all gaskets head intake manifold exaust manifold ect. Now when i start the motor it is running rough and is knocking and screeching. It is not a lifter tick. Kinda of sounds like it is coming from the timing chain case? Any ideas?
