Use a Bernzomatic torch and a little elbow grease to loosen frozen, rusted or stubborn nuts and bolts. For stubborn bolts, heat the bolt, then move the flame away and apply WD-40 against the heated bolt threads. The melting wax pulls itself into the threads to create a slippery surface.

Does heating a bolt loosen it?

The answer is surprisingly simple: the bolt expands, but the nut expands more. What is happening here is good old thermal expansion: The bolt is heated and expands outwards, its radius increasing.

How do you heat a seized bolt?

Torch Your Stuck Bolt

Now heat the bolt and nut. Put the flame directly over the stuck part, or the part you can get to safely. Heat it for 30 seconds or so and it should free up easily. If it doesn't, repeat the process to see if that helps.