How to Repair Cross Threaded Bolts
Cross threading occurs when the threads of a bolt shift off centre and cut into the female threads of a threaded hole or nut. The cross threading damage caused by the bolt occurs in the top female threads of the threaded hole or nut.
Cutting new threads on the cross-threaded bolt and the damaged female threads will repair the damage.
Match a socket to the head of the cross-threaded bolt. Attach the socket to a ratchet handle. Turn the bolt counterclockwise to remove it from the part.
Thread the bolt into a thread gauge.
Select a tap matching the diameter and the thread count of the bolt into a T-handle tap wrench. Pour cutting fluid onto the threads of the tap and damaged part threads.
Turn the tap clockwise to thread it into the damaged part threads.
Set the head of the bolt in a vice with the bolt threads facing up. Lock the head of the bolt into the vice jaws.
Secure a die -- matching the bolt's size and thread count -- into a die socket. Turn the die socket clockwise to cut new threads on the bolt.
Thread the bolt into the threaded part.