backhoe swing chain

[gyhkl]

One of the bolts that connects one end of my Mahindra's backhoe swing chain to the hydro cylinder that moves the hoe left-right is broken off. The lower half of the bolt(with the hex head) is gone and the top half is still threaded into top half.
Can anyone advise me as to the best way to get the rest of the bolt out and thread a new one in it's place? I doesn't look like an easy-out would be work here.
I there a way to loosen the chain to make things easier?

Thanks.

 

[Sebculb]

Is there any amount of exposed area in a useful place to weld to? I like to weld new bolt heads on, or pieces of pipe that can be wrenched on like a breaker bar, or even small pieces of rebar or whatever is handy that can be grabbed with​ a vise grip or an adjustable wrench. The heat helps too.

 

[gyhkl]

The part left in the hole is just below the surface. It would be nearly impossible to weld a nut to the threads without welding the whole works in the hole. I probably wouldn't have to grind much off above the hole to take the metal down to the bolt though. I might be able to make it work that way.
Thanks for the help.

 

[GLyford]

There's lot's of youtube videos out there on people welding nuts on broken bolts in exactly the same situation, bolt end below the surface, and they do it without grinding it back. Some just weld a nut, some weld a washer and a nut.

I would think grinding around the bolt hole would make it more likely to stick something by giving a clean metal surface, right now there is a layer of paint/rust/dirt/grease keeping the weld from sticking very well to the surrounding metal.

 

[GLyford]

Another thing to try:

Grab a set of left hand drill bits. If the bolt broke because of tension under the head and the bolts threads themselves aren't too rusted to turn, the drill will sometimes catch and back the bolt out for you. If it doesn't catch then you have a hole in the bolt you can drill larger, pick out the threads, and run a tap through to clean up.

Harbor Freight has a set. Left Hand Drill Bit Set 13 Pc