The Stovebolt Site Forums The Shop Area Engine Shop Removing my well-rusted intake/exhaust manifold

What's the best way (tried and true) to remove well-rusted on manifolds. And, what's the product that's applied to the manifold side to eliminate leaks. (some copper something)?

Be sure to soak all the bolts down with good penetrant like PB Blaster,, Kroil or something of that grade. Using a GOOD boxed end wrench, try to tighten just a little at first then loosen. If it starts to get tight when loosening, spray a little more penetrant on the bolt threads and re-tighten a little then back it off . If it gets tight again, let it sit and cool down as the bolt/nuts will get hot from friction and cause the bolt/stud to break.
If that process does not work well, use heat and let cool, use heat again and let cool again. It will not hurt to heat and let it cool a few times.

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The best method I've seen work is to heat up the manifold around the bolt you want to remove with a torch. Get it glowing and then very gently work the bolt out. The idea is to expand the cast metal of the manifold which allows the bolt to spin. While I definitely recomend the torch method, the best penetrating oil I've ever used is an AC/Delco product available at a GM dealership. Used to be called Super Penetrant and is now called something like Rust Inhibitor and Heat Valve Lubricant. Good luck.