A product called----LUMIWELD-----or similar will fix this.----An aluminum brazing rod.-----color will be different than the aluminum of your pontoons.----A darker shade once weatherized ( is that a word ? ) after a while.
The primer VALVE is not used to adjust mixture.---I think you need to revisit carburetor cleaning.-----Or consider the simple task of removing cylinder head to inspect in there.-----Compression values are LOW on your motor.
Carburetor has nothing to do with starting.----Are you pushing in the key in while cranking it over ?-----The electric primer valve puts fuel directly into the intake air.----This fuel bypasses the metering circuits of the carburetors.
It has been clearly stated that ---" spritzing fuel / oil mix into the top carburetor there is no change at all "----- This issue should be so easy to resolve !!
