I don't know if it is an NT carb the air filter is black and it looks like an scary skull ghost. The air inlet is on the bottom. When I first put gas in the tank it started leaking gas from the air filter gushing out gas. I took it apart and inside the float where the needle pin is it where the flimsy metal part that holds the needle was bent so it was not attached to the needle I fix it and put it back together and no more leak. I just finished adjusting the throttle cable at the throttle handle and at the carburetor pulled the carb needle out and I'm going to test it now . I will let you now how it goes latter. also you said something about no more than 24:1 The manual said to do 16:1 to break it in and the after break in 20:1 Also I read some where to brake it in with standard 2 cycle oil and then go to synthetic 2 cycle oil.