Removing a broken exhaust manifold stud is tricky as it can require simply using Vise grips to loosen it by hand or a drill to completely dislodge it, ruining the surrounding threads. Manifold studs are exposed to high heat temperatures that can cause the bolt to expand or rust overtime.
There are several ways to approach a broken stud. The most efficient way requires using a drill to completely remove the stud in its entirety. Before attempting to drill out the stud, try removing it with basic hand tools. Drilling out the stud will ruin the thread for the bolt. The following instructions explain how to do so.
- Grind the stud down
- Locate the center shaft
- Drill out the stud
- Tap a new thread In
Take a file and grind the stud's end down to an even surface.
Use a smaller in diameter sized drill bit on the shaft of the stud and begin to drill into it. If the drill can make it all the way through pull it out and then repeat with a larger sized bit.
Attach a larger sized bit and drill out the remains of the stud. Doing so will also remove the mating surface for the stud.
After drilling it out, tap a new thread inside the engine head so another stud will be able to be installed.