Step one, its dirty clean the jets and the whole thing, if that does not work then, step two get a rebuild kit, not a new carb, boating is not turn the key and go boating, boating is do the maintance then turn the key and go boating, the minimum maintance ,spin on water separator, battery maintainer on battery 24/7 when not boating, fogging oil at start and end of your boating season, , marine gear lube lower unit, every year, impeller/water pump every year, are the plugs ok, spark checker at HF, and clean, drain carb bowl at the end of every boating season, or all fuel for that matter, Do the maintance, or boating is going to be one big disappointing bummer, its a lot of work to have fun.