Chainsaw Repair

(Flywheel removal using Husqvarna "knocker" service tool)

What keeps this tool from messing up threads and exactly how does it work? Does it have something inside to take up shock to threads?

I usually just put the nut on 3/4 on and tap till fly breaks loose. Yesterday I had a impossible fly to break loose. So when I went to remove nut it removed the threads on the crank end and also stripped out the threads inside the fly nut.

So I broke out my mini 3 jaw and pulled fly right off.

Put new flywheel and new nut back on and all was good to go with a buggered up crank end.