Take the pull start out (Before that put on working goggles, and put on a long sleeve shirt) you don't want that cobra (the coil) to bite you when it comes out of that little place.

Carefully take the starter out and check. there might be something that is preventing the pull start to go back. check the coil (Fix) and put it back making sure all the screws are tight and everything inside the pull start sits right on its place.

there are videos you can watch that i put on youtube.

How to Fix the Pull Starter Part I
http://www.youtube.com/watch?v=kW2M3AoTVZo

How to Fix the Pull Starter Part II
http://www.youtube.com/watch?v=MH5Owx5YcJY


Cheers

Ali