If the bolt is covered with orange streaks or bits of rust, it is a good idea to scrub them away with a wire brush. As close as possible to the problem, squirt a penetrating oil like Liquid Wrench on the threads. It will take time to soak in. You should let the oil work for as long as possible.
Let's Get It Fixed!
HomeX virtual experts will assess your issue (for free!) and can resolve simple problems.