Questions and Answers

Another Broke Bolt

Q. I have a '72 chevy nova with a 307 engine. It has single exhaust

The pipe that enters the muffler has a few holes in it so I thought of replacing the whole system. Here is my problem: trying to get the pipe off at the exhaust manifold I broke the stud. I'm attaching a picture of the area that I copy from a book. How can I fix this? The other problem I have is how do i get the other 2 bolts off. I'm afraid of using a torch in the area.

Thank you very much in advance for your help.

A. There are three things in life that are certain, death, taxes and chevy manifold studs will break. I must have drilled out hundreds of them in my career. The problem is they are too small and when they rust, they rust down to nothing. Personally, I think it's a design flaw that GM never did correct.

I wish I had some sage words of wisdom for you, but unfortunately, I don't. All you can do his heat the nut, not the stud, cherry red and try to turn it off. A lot of the time this works. Other times it doesn't. That's when you get out the drill and a good set of drill bits and go to work. I explain the procedure in A Broken Bolt.

If you can take the exhaust manifold out, it will be a lot easier to drill and tap. Or you can take it to a parts store like NAPA that has a machine shop and they can drill and retap it for you.