Welcome to the RCU forums, clay3D!

After tuning the engine, grab it and point the nose up to verify that will not die due to having to pull the fuel all the way from the tank while keeping that attitude in 3D flight.

If it dies while pointing out, open the needle valve a little and try again successively until the engine keeps running and properly transitioning in that attitude.

Check for mixture adjustment at this webpage:

http://www.gettingairborne.com/engines.html

Best luck!