Snakeoil for a cracked header?

Have a cracked header on a 90 ltd. it's above the crotch of the Y on the inside. I've tried several things like that toothpaste looking stuff, but it never works.

Has anyone had any kind of luck with any kind of manifold patch?

I know JB weld is good for about 650* but i can imagine the manifold exceeds that at times.. I bet it could be re-welded much easier.. that is, if you have the resources to do so.. But at this time, i cant think of a patch system that would be worth trying..

Since a proper welding repair requires you to remove the manifold, you might as well install a new one, because most XJ exhaust manifold repairs are not successful.

There is no magic product that will fix a cracked exhaust manifold.