In article ,
Don Foreman wrote:

My experience has been that if I can get the bolt and the metal it's
stuck in glowing dull red, it will come out without much of a fight.
Heat above 1200 degF heat must do something to rust.

Yup. Rust holds water, and it swells. Hot enough and you drive it off,
and it shrinks. Also why loctite, or antisieze, or at least grease
should be on every threaded connection that will be out in the ugly wet
world.

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