hwyengr

I have two broken shoulder bolts in one of the heads. Doing a search has returned that the only way to break the Super Loctite bond is with a MAPP torch. I'm okay with the process, but doesn't putting a crazy amount of localized heat near the cam cover gasket sealing surface risk warping the aluminum?

Should this process be aborted for a helicoil fix?

Dave928S

You can more safely get enough heat to a bolt that you want to get out, by shielding around the bolt with some fire resistant fibre cement sheet with a hole in it just big enough to drop over the bolt, then hit it with a welder on the end. Only works if it projects a bit, and is not broken off flush. Disconnect electronics before welding.

MAPP gas torch is OK if you can adequately shield the head in a similar fashion, so that you only apply heat to the bolt.

Another way is spot face the end flat with a file, accurately centre punch, and then use a left hand drill bit to 'core' it out.

Helicoil would be last resort if you bugger the thread.

Mrmerlin

NOTE that heating/ welding the engine to remove bolts the coolant should be removed first.
I would not worry about warping anything with the Mapp gas torch,
it does heat faster than propane but the aluminum transfers the heat so fast it would take a few of these torches to get any appreciable amount of heat into the heads or block