Exhaust stud broke, peice of head came with it?!?!?

[meet07]

I had a exhaust manifold stud break off my head about 2 years ago. It never gave me any problems but I would like to fix it. I don't have pictures but I can describe what it looks like. The threads are still in the head but there about half way into the head. The beginning of the threads are missing.

What are my options? It appears that I can not re-tap the threads with the same thread pitch, and need to drill bigger and tap again? Has anyone ever done that ??

Thanks

[240z4u]

I'd use time-serts in this application. They won't back out like helicoils will.

[huafist]

I'd use time-serts in this application. They won't back out like helicoils will.

Agreed - but from what I'm understanding, part of the stud is still in the head? You need to get that out first. I just removed two broken studs from an RB25 head that were broken off below the surface. I used a MIG to build a weld up on the stud until it cleared the head, then welded a washer to that, and a nut to the washer. That allowed me to use a ratchet to remove the broken bit of the stud.

[240z4u]

I'd use time-serts in this application. They won't back out like helicoils will.

Agreed - but from what I'm understanding, part of the stud is still in the head? You need to get that out first. I just removed two broken studs from an RB25 head that were broken off below the surface. I used a MIG to build a weld up on the stud until it cleared the head, then welded a washer to that, and a nut to the washer. That allowed me to use a ratchet to remove the broken bit of the stud.

You may be correct upon reading that a 2nd time, it does seem that he's got broken off studs. I thought that he meant that the threads were pulled out of the head.

[meet07]

my bad. the stud is not stuck in the head. The head still have threads....my bad, typo

[meet07]

I'd use time-serts in this application. They won't back out like helicoils will.

I did a little bit of research on the time-serts kit and there not cheap. I believe the kit for M10x1.25 is around $400.00 bucks plus. Any other alternatives besides taking it to the machine shop. I'm capable of doing it in house

Well if part number: 1012 is right then the kit is around 80-100 bucks. The inserts are a hair over half an inch in length. Would that be enough thread?