June 6th Update! Run down battery = being towed .... towed too FAST = water in cylinders. Long story short.... take spark plugs out. Let water drain. Pull safety switch @ helm, crank until no more water comes out. Now it's dark. We injected 2 stroke oil into each cylinder and waited for daylight.
Now we took it back to the water. A mercury mechanic was with is now (friend of a friend that was visiting for the day) and he got it started. We ran around in it and it took a little while to get all of that oil burned out. Replaced spark plugs. NO MORE WATER in engine.
Ran it all day on the lake.
The only problem we had then and still have is that it's running VERY rough at 1/4 throttle and after a while idling (2 mins approx). WOT seems to feel ok but only getting 5500 - 5700 rpm. We've replaced coils & spark plugs again.
Spark plugs appear to be dry and running very lean.
We had it out yesterday and then again today. No change.
Runs rough [emoji30]
Compression 1,3,5 = 110 2-100, 4-110, 6-115
I'd appreciate suggestion on possible causes/ solutions.