Stripped exhaust manifold bolt threads

[steven.collett]

Recently aquired a 450 Chim that has lost 3 bolts from the exhaust manifold. On inspection it appears that the internal threads have been crossed/stripped so there is limited scope to get new bolts in. Does anyone have any experience of this and/or ways to resolve it without having to get the head off to re-thread the holes?

[The Surveyor]

Access is a PITA, i would think the head would have to come off for that!

[old64er]

remove manifold and use a helicoil set?

[Martin_S]

old64er said:

remove manifold and use a helicoil set?

Remove heads and use a helicoil set, if you don't want to run the risk of making the problem even worse!

[steven.collett]

Thanks for the suggestions. It appears as though the bolts have located and sat in the thread OK although I'm told that they may not take too kindly to coming out again so problem resolved for the short term at least.