G'day Mate,
First thing, have you changed your glow plug? I use OS Type F, in my 4 strokes.
Next the prop should be Ok, but make sure your idle mixture is set as lean as it needs to be, to run the motor, don't leave it a "bit rich", when you use the pinch test, it should pick up revs very slightly, before cutting out, this may make a difference, try it & see.