I have what seems to be a very small leak at my left exhaust manifold. 1973 450sl. It's not a big deal, and I don't want to have to replace the gasket. Has anyone had any success with just re-torquing the bolts? Anything wrong with trying this?

I just noticed in my Haynes manual that it says at 30,000 miles to "re-torque the manifold bolts." I guess this includes exhaust manifolds. The manual isn't very good at explaining exactly how to do this, or at least not to me.

Exhaust manifold bolts in my experience are best left alone if possible. The reason is that they often seize in the head due to the extreme temperatures and the effects of rust. So if you might break one off while removing it, you might break it off while retightening it also.

But I tend to be less picky than most people about small leaks.

Ken300D

On the other hand, if you don't exceed the torque specification anyway, then applying that amount of torque won't hurt anything.

It might not move the bolt, but it should not break it or shear it off either.

So really, you have nothing to lose by applying the correct torque to the bolts on the exhaust manifold.

Ken300D