Boat cranks up every time won’t pick up speed in water

[BROUSSARD2]

Have a 1996 Mercury Force Motor I’m working on. Replaced all fuel lines. Cleaned tank. Replaced plugs. Measured spark. Ohmed the stator. Verified coils are good. Motor cranks up and idles immediately on first turn in water or with muffs. Will get speed up to about 10 mph but when you give it gas it stays right there. Sometimes it will catch and run like a champ for an hour. Turn it off. Crank it back up it has the same issue. Not sure where to go with this motor. Never seen this on any outboard I’ve worked on. Took the foot of to check for carbon. Nothing. Prop is good. Any advice or any other rabbit holes to go down would be great. Thanks guys!

 

[RUSSELL613]

I had a 115 force back some years and was doing something like that, found out one of the carbs. Was flooding out, have you checked them?