For what it's worth, I had to remove two broken studs on my Ford Ranger
V-6 after the wife hit a rock and snapped the exhaust manifold. In
removing the broken manifold, two bolts broke off. The studs left a bit
of the bolt above the surface. I drilled the threads out of a stainless
bolt so it would slip over the protruding stud. Using a stainless
welding rod, I arc welded the nut to the stud. The broken stud came out
with surprisingly little effort.
When stainless steel cools, it shrinks rapidly initially, really! The
concentrated heat from welding, and the shrinking of the stainless
breaks the bond between the stud and head. Almost always works.
However if the welded nut twists off and any stainless weld is left
behind it will be hard to drill. At this point you will probably not get
the broken stud out without removing the head anyways.Take it to a
machine shop.
When replacing exhaust bolts it is advised to use black oxide bolts. Do
not use plated bolts as the plating will disintegrate in time and cause
the bolts to seize again. Higher grade bolts are most often plated.
Be carefull when using anti-seize on the bolts that you can easily
over-torque them, just like over-torquing oiled wheel studs.
Regards, Gil
V-6 after the wife hit a rock and snapped the exhaust manifold. In
removing the broken manifold, two bolts broke off. The studs left a bit
of the bolt above the surface. I drilled the threads out of a stainless
bolt so it would slip over the protruding stud. Using a stainless
welding rod, I arc welded the nut to the stud. The broken stud came out
with surprisingly little effort.
When stainless steel cools, it shrinks rapidly initially, really! The
concentrated heat from welding, and the shrinking of the stainless
breaks the bond between the stud and head. Almost always works.
However if the welded nut twists off and any stainless weld is left
behind it will be hard to drill. At this point you will probably not get
the broken stud out without removing the head anyways.Take it to a
machine shop.
When replacing exhaust bolts it is advised to use black oxide bolts. Do
not use plated bolts as the plating will disintegrate in time and cause
the bolts to seize again. Higher grade bolts are most often plated.
Be carefull when using anti-seize on the bolts that you can easily
over-torque them, just like over-torquing oiled wheel studs.
Regards, Gil
