Try Paraffin wax on your next stuck and rusty bolt or stud. Heat the (exhaust?) stud until the thing is cherry red, then apply a stick of Paraffin wax to it for a couple of seconds. Clamp your vise grips on it and back it out. It is also called canning wax. I used to use that about every day in he old M/C shop....
I believe the wax melts and is drawn down the threads to break the bond between the stud and the manifold.
The heat pulls the wax in and becomes a lubricant. It might flash on you as well, so hit it again if it does. Not to mention the different expanion rates of the two metals, one will expand fast and or more than the other which will help. Just don't cool the thing too much with the wax. Break it loose while it is still pretty hot.
You have to use a torch, MAP gas doesent get the area hot enough....works VERY well....Bobb Makley showed me that trick years ago. Good to keep us reminded of what works!!
Forgot about the torch thing :TU: I read this in an old car craft, or hot rod? Anyway, I used it for years in the engine shop (s) that I worked in... Lots of stuck rusty bolts in daily driver exhaust manifolds / heads. Good luck
My grandpa used that trick in the 30's........another one he used an a car that smoked because of worn rings 2 tablespoons of Bonami down the carb whle running.. it scored the cylinders and roughed uo the rings and the smoking stopped, he was a mechanic and guaranteed for 50 bucks he could make it stop smoking,,,it works...if you can find the stuff, its like comet...
