Heating shoulder bolts for extraction. How does the head not warp?
#1
Heating shoulder bolts for extraction. How does the head not warp?
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?
Should this process be aborted for a helicoil fix?
#2
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.
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.
#3
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
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