The reason why I brought up compression is because I have a bad hole on my v4 crossflow. The only reason why it comes out of the hole is because I have really high compression in the other three.............in the 140's. Even then, it'll bog down sometimes and not come up. I have to feather the throttle sometimes. I thought Mercs were higher compression motors. The only motors I know of that run on compression in the 90's is the v6 crossflows......meaning that's good compression numbers. I am re-ringing a v6 of that type as we speak, and it had 90-95 in all the holes. That's normal for that motor with bathtub heads. I most certainly DO NOT know all there is to know about outboards.............especially those black ones. It sounds like a compression issue to me.