HELP NEEDED EXHAUST STUDS SNAPPED

[MattW]

The stud is stuck , meaning there is no clearance between the stud and the tapped hole it is stuck inside. How is expanding the stud going to create the clearance required to undo it?

The idea is that thermal shock and diametrical expansion of the stud will hopefully unstick the corrosion bond between stud and tapped hole.

However, I'm not a fan of the technique. It will also weaken the tapped thread and anneal the alloy making subsequent failure more likely (I've seen it happen). I'd be drilling and helicoiling but each to their own.

 

[JayC]

The idea is that thermal shock and diametrical expansion of the stud will hopefully unstick the corrosion bond between stud and tapped hole.

However, I'm not a fan of the technique. It will also weaken the tapped thread and anneal the alloy making subsequent failure more likely (I've seen it happen). I'd be drilling and helicoiling but each to their own.

I understand the practise of applying heat to release one item from another, but the heat, if that is the chosen method, should be around the stud, not on the stud. The goal is to expand the surrounding material that is holding the other piece fast, not to expand the piece that is being held, in this case the stud.

As an example, to release a bearing from a housing you localise the heat source at the housing, not the bearing. To remove a bearing from a shaft you apply the heat source to the bearing, not the shaft.

I refer back to my OP, to take it to a machine shop to have it done both properly and accurately.

 

[MattW]

I understand the practise of applying heat to release one item from another, but the heat, if that is the chosen method, should be around the stud, not on the stud. The goal is to expand the surrounding material that is holding the other piece fast, not to expand the piece that is being held, in this case the stud.

Yep.
However this technique is much less subtle and brute forces the seizure through the expansion and contraction of the stud. It can work and i'd try it as a last resort on a bigger stud screwed into a stronger base material but not soft alloy.

However it's not my bike...