I have ordered a chambered exhaust system for my '69 L46. In preparation, I will be replacing the manifold studs. Should I remove the manifolds to get the best 'angle' for stud removal? Also, need tips and suggestions for correct approach to removal.

Thanks!

 

Ted,

It is a lot easier with the manifolds off the car. The studs are a real PITA if they have never been out. The best way to remove them is to soak the threads in PBlaster for at least 2-3 days. Double nut the stud and then try and remove it like a bolt. You could also try heat with a propane torch. Heat up the manifold not the stud.

If all else fails and you break one off then you have two options. A stud removal tool (looks lie a nut with screwed threads inside) or drill it out. I prefer the drill method myself. Cut the broken stud flush with the manifold. A cutoff wheel or hacksaw will do the job. Then punch EXACTLY in the centre of the stud to mark it. Drill in steps up almost the same size as the stud. You can buy REVERSED drill bits which are good for this job.

You can try an easy out but I really don't like them for this job. The manifold is very brittle and if you wedge an easy out down there you will break an ear off like I did. If you drilled straight and center then you can pull the stud out like a piece of drill swaff. If you used reverse drills you will get to a point where the stud should start to turn itself out.Worst case you can drill the stud all the way out and retap the hole.

Take you time and the manifold should survive.

I replaced my studs with stainless and used neversieze on the threads and now the come straight out.

 

That can be a nasty job as the studs tend to get thin with time. I did that job with the manifolds on the car. Even with a good soak of penetrating oil, acetylene heat, and a stud extractor (see pic) I snapped off two neatly flush with the manifold. At that point the drill came out. It was a tedious, dirty job that I will leave to muffler experts in future. It wasn't worth the time and aggravation to save a few dollars.

I thought of removing the manifolds at the outset but with my luck I would have snapped off some bolts in the head.