My 2 cents,

1. Change the Glow Plug and see if that helps. Go ahead and change it even if you take it off, put the glow starter on it and it lights.

2. If that doesn't work, try making some small (1/2 turn) changes to the high speed needle valve. And try to start the motor between each change. Remember where your starting position was, just in case that isn't the problem.

If a motor won't run, or run right it's either a "fuel, fire, or air" problem. Somewhere in those three things.

If you've done all these things and it still won't run, I'd suggest moving your thread to the "engines" forum and asking there.