ISX cm871 in frame overhaul nightmare

[DieselKid]

Definitely don't use a helicoil! How did you manage to strip the threads out? Crossthreaded?

Do you have access to quickserve? There should be a thread salvage procedure that requires a fixture to align and repair your hole. You have to ream it out and tap for an insert. The challenge is getting the new hole drilled and tapped straight to prevent the block from cracking. I'd suggest cleaning the hole and surrounding surfaces and inspect for cracks with a crack-check spray before moving on to fixing it.