Welding to get a broken bolt out of engine block

[Sberry]

A good repair will last the life of the engine. As for 030, nothing wrong with it but with either you need to crank this machine up as far as it will go. I agree with washer welding first, gives some shielding and lets you put some heat on. Second, a little metalurgy. I try, if it doesnt work often tweak a lock washer so the tang doesnt grab and weld a lock on first. Gives it a little twist power and agree with wrench rocking back and forth. This is no place to give up quick.

[BeachComber]

A good repair will last the life of the engine. As for 030, nothing wrong with it but with either you need to crank this machine up as far as it will go. I agree with washer welding first, gives some shielding and lets you put some heat on. Second, a little metalurgy. I try, if it doesnt work often tweak a lock washer so the tang doesnt grab and weld a lock on first. Gives it a little twist power and agree with wrench rocking back and forth. This is no place to give up quick.

I disagree with needing to crank up the machine using 0.030 wire for bolt extraction. Broken exhaust manifold bolts are a common occurrence on the Hemi engine family. Just did a 5.7 Hemi over a week ago that had a broken exhaust stud, flush with the manifold. At work, we use Lincoln 140 with 0.030 wire and C25 gas. I set it at C and about 8 on wire feed and fine tune if needed. Use vise grips to pull the bolt out after soaking with rust penetrate (galvanic corrosion with the steel bolts in aluminum heads is a problem), then just twist them out. Trying to weld a washer or nut on a broken bolt, tends to be a waste of time at least when I've tried. Just better off stacking weld on it enough to get a vise grip on and extract.

[Sberry]

I was thinking, how far it would fill a coffee can if I had saved all the broken bolts I have removed, not only wire but sticks too. Hundreds of them.

[Sberry]

Are you sure about the settings on the 140? C is about 3.5 with 023 solid. I mention a lock washer as the add mix of a bit of carbon from it gives the weld a bit more twist power.