I just broke in my 46 and I've been running a 55. Mine when running way rich will run at half throotle and when advanced to full will sputter and die just like it is lean but it is RICH. Keep that in mind for next time. I have also flooded my 55 and it takes 30 seconds or more at half throotle before she will fully rev up. That sucking sound could be a rich engine. For starting I put finger over carb and turn prop 3 times and they fire right up. You will get the hang of these motors and it is a lot of fun after that. Good luck.