You got carb issues is my guess.I'll label my trouble shooting
1. Rebuilt both 1048 and 257 carbs with all new internals and pop pressure checked.
2. Changed coils.
3. Went in both directions with needles.
4.re sealed the entire engine.
5. Using a known good plastic isolator.
6.new piston ring and checked scoring. Engine has only 2 hours on it but it's a 2nd hand engine
7.good clean fuel
8. Boat has a water pump and I just rebuilt the pump with a new walbro rebuild kit.
So my latest observation is when I run the engine for a few minutes I pull the plug and its soaked...I was told try one heat range hotter maybe it will help
I wonder if it was an air leak I would need more fuel to get the engine to behave better but it's acting like it wants more air
Are you sure carbs are back together correctly ? Double check them. Wet plug is a skewed carb. What were they opening at ? Did you adjust pop off on them from stock ?
The one screw fuel pump section the thin diaphragm and flapper section go on the body first then the gasket then the cover.
Not all the gaskets and diaphragms are always apples to apples in some rebuild kit. Some kits require two pieces to replace what was one originally.
On the four screw side the gasket goes on the body first then the then diaphragm on top then the cover. Opposite the way on the other side..