you have to go though the troubleshooting of any engine. Some of my student had these and they work ok.
1) check the tank fittings, cracks and pin holes in fuel line.
2) is the fuel tank nipple even with the center of the carb?
3) pull and clean the carb. remove rubber o rings and clean with carb cleaner shootin through all ports.
4)check for air leaks around carb attach point, can seal with high temp rtv, I've had to do this with every tower motor I've gotten.
5) what plug did you use, you need to have a plug in the right temp range. 10-15% nitro would be a med temp plug. 5% a cold plug and 20+ a hot plug.
6)start the engine, lean out the high end needle, if i still doesn't go the full. reduce to idle and pinch the fuel line. if it dies right away richen the low end needle, the flat head screw in the center of the barrel. If it speeds up and dies it's too rich and need to be leaned out. 1/4 turn at a time. With a good pinch for 3-4 seconds it should start to slow down and slowly die. try the high end again.