Wow, Livermore Cali, home of Airborne Models, the exclusive importers of World Models ARFs!!!

Anyway, welcome to the nitro boat forum. Looks like your thread took a while to get here. Since boat engines have very little load on them, they should be started with the carb almost all the way closed. It's possible you have the carb open too much. It's also possible that you have the needle valve set too lean. When the needle is in the right ball park, the engine will seem like it's way too rich. This is ok, it will run better when the boat is in the water and the engine has some work to do. It's a bit of a juggling act to keep the engine fast enough to have it not stall, but not so high that it damages itself. If the engine revs well while it's out of water, in all likelyhood, you have the needle too lean.