Hi!
Don't dismantling the engine...there is probably nothing wrong with it!
The problem you have seems to be the idle speed needle! If it is turned in too much the engine will be very difficult to start because ithe low speed needle stops the fuel from entering the carb when the throttle drum is set to idle position.
Just upen the idle needle some and see what happens.

Second are you using the correct fuel?
You should use at least 5% nitro and not more than 15%. Prop should be 11x6 , preferably APC.
Glow plug OS or Enya 3,
High speed needle open 2-2 1/2 turns.
Fuel tank size : 8-10oz.