Frank Thompson writes:
Any suggestions for removing frozen nuts and bolts on exhaust manifold/
exhaust pipe
connection on old MF135 tractor? Am using Liquid Wrench w/o success.
I want to be careful not to break bolts.

Two methods I've used on bolted-together auto exhausts:

- Heat the nut with small hot flame, ideally an oxyacetylene flame. Try
not to heat the bolt directly, just the nut. When it starts glowing
red, use a wrench to unscrew it.

- If the above doesn't work, switch to the cutting tip. Heat one side
of the nut hot enough to cut, but again try to keep the bolt cool. Hit
the oxygen lever for a moment. If you've timed it right, you'll cut
right through the nut (because the steel is hot enough to burn when the
oxygen hits it) without damaging the threads on the bolt (which is still
too cold to be affected).

It might be worth trying the latter technique on some scrap bolts and
nuts until you get the feel of it.

Dave