gandalfnz
RCTalk Addict
Your carb needs to be fully open at full throttle, when you let go (neutral), it should return to idle.
Simple way, when you apply brakes, your carb slide should not be moving the tiniest bit.
Make sure you have no leaks in fuel lines, tank....etc, when you put your finger over the exhaust stinger and crank the engine, you will see the fuel flow from the tank into the carb, this means you have no major air leaks.
Check that the glow plug is good.
If you have throttle trim knob on your TX, give it a bit of an increase in throttle, just a tiny bit, you don't want a runaway right on start up.
If the engine is healthy, leak free and carb is clean, it should fire right up.
Good luck
