Questions and Answers

Monte Carlo Manifold Studs Q. My son bought an 1988 Chevy Monte Carlo (4.3 liter V-6) with a blown head gasket. He and a friend who's graduating from an auto mechanics school in May are doing the job themselves (with some advice from dad). In the process of undoing the nuts from the studs on the exhaust manifold where the exhaust pipe connects to it, all three of the studs snapped.

My first thought was to drill out the remaining stud piece and just use stainless steel nuts and bolts going back. In looking it over, I'm wondering how those studs were in there and whether these are replaceable parts. (Also, I'm surprised to see that the threaded portion is a 3/8" bolt size but the non-threaded piece is 5/16".)

Do you know, are they pressed in or perhaps they're a left hand thread? Again, these are on the exhaust pipe end of the manifold and are used to secure the pipe to the manifold. Any insights would be appreciated.

A. They are regular threads, no tricks here. If the manifold is off and in your hands it will be much easier to drill them out. Once you get them drilled to 1/4" you should be able to apply a little heat and use an Easyout® to remove them. DON'T put heat on them before drilling or you may temper them so a drill won't go through them. You could also just drill new holes and rethread them with a bigger bolt/stud as long as they fit through the pipe flanges.