Removing broken head studs from block

[Joe K]

Put in to the "neck" of the thread is my usual discovery. This would be the two or three threads at the top of the threaded portion where the thread is not fully formed. The thread at that portion "jams" in the correct size hole, and causes an "interference fit" between the stud and block.

My best luck as been in successively "drilling" the stud until you get to a "spiral" of metal. Off center CAN be a problem. And as you say it's the "heat" of the drilling which actually loosens the connection.


Joe K