TIG use case - remove broken bolt in manifold

[indy4x]

Have used easy outs, generally don't work on rusted studs or bolts, have had 100% success on snapped bolts that were overtightened and then sheared.

My usual solutions have already been discussed, either drill out and then pick out what's left of the thread or weld a nut onto the broken bit and the heat normally helps break the bugger free

Edit:, yes I do use a torque wrench but found out the hard way rebuilding a diff it was way out of calibration

 

[Pete.]

^^^ but the only reason for the snaping is there seized ?

Nope, as above if you stretch one by over-tightening it can be stuck in the thread too tight to wiggle out but not much effort to remove with an extractor. Also fatigue cracking - we very often have to remove hydraulic breaker accumulator bolts due to cracking. I like this because I take the large broken top section out of the scrap bin and make stuff from the lovely tough 12.9 grade steel.

 

[Olli]

Here’s some information I found, which also pertains to broken bolts in classic cars ....
http://www.madelectrical.com/workshop/broken-bolts.shtml
Today, I’ve practiced a bit on my testing ground (see one of my previous posts). The welded nut from last test that looked good, broke off too easily when I applied force. So I thought about combining some approaches: I’ve drilled a small hole in the stud about 1/6” deep. Then I welded a tower on top and finally a nut to the tower. This weld appears to be sturdy now. In the pictures attached you see the situation ... it is supposed to depict a situation where a bolt is broken off 1/8” deep. In the first picture the lower nut represents the surface of the part and the upper one is welded to the created tower that bridges the gap between top of “broken” bolt and nut.
The last picture shows the created tower - the fact that the lower nut can be screwed down shows that the part wouldn’t be welded to the bolt or tower - another crucial point.

Olli

 

[cr500dom]

snap-on do a splined extractor set, includes drill bush to guide the drill, cobalt drill bits, splined extractors, nut splined sleeves to fit over the splined extractor (And apply the force as close as possible).
They are superb.

https://shop.snapon.com/product/Combination-Extractor-Sets/19-pc-Extractor-Set-(Blue-Point®)/E1020

 

[Munkul]

Olli, if that stud is snapped deeper than the diameter of the bolt, then what you're proposing is nigh on impossible.

The biggest problem is going to be avoiding welding or damaging the threads of the cylinder head, and you CAN'T put copper paste or something on them, you'll just contaminate the welding arc, it just won't work.

If you can clearly get a TIG arc and filler in there like you can with your nuts and bolts practice, then fair enough... it just looks like it's way more recessed than that in your pictures.

I honestly wouldn't be attempting that method at all, it's too small and fiddly a bolt and the head isn't aluminium, so your margin for error is tiny.

I'd be drilling out out like a normal person. However... IF you manage to do it... good luck anyway!

 

[northwest]

snap-on do a splined extractor set, includes drill bush to guide the drill, cobalt drill bits, splined extractors, nut splined sleeves to fit over the splined extractor (And apply the force as close as possible).
They are superb.

Yes, I had a set. As you say, superb. I gave mine to someone who turned out to be a complete Cockerel. Hey Ho.