Rusted and broken bolt removal. Asking for all ideas.

[robotmaker]

I have searched and found but only a couple references to rusted bolt removal, but haven't seen any good suggestions on how to get out a bolt with a broken off head. I have a couple that have just the head gone which still gives a stud to grab ahold of, but I also have a couple that are broken off below the surface. Besides using an easy out, does anyone have any other suggestions on a better way to get these boogers out? I saw the suggestion about the heating and impact gun, but that is obviously not going to work here. In case it makes a difference, I have several broken off which holds on bottom rollers and rock guards that HAVE to be removed in order to install the new parts. Any suggestions from all you old timers will be GREATLY apreciated.
thanks.
rj

[jdemaris]

I have searched and found but only a couple references to rusted bolt removal, but haven't seen any good suggestions on how to get out a bolt with a broken off head.

Broken and/or stripped bolts probably take up more repair time than anything else on old crawlers and undercarriage work. Every situation is different - but here are few things we had to do over the years.

Easy bolts might respond to a simple left-hand drill bit . . . or . . . a drilled hole and a good quallity not-so-easy out.

Broken bolt with a piece sticking out? Weld a nut to it. Then heat the area around the bolt and try to turn. Try to heat fast with a rosebud. If you do it too slow, everything gets hot and expands. You want the metal surrounding the bolt to get hot first.

For bolts broken off flush. Sometimes - you can sharpen a bolt to a point and still weld it to the broken one. If it's too recessed - drilling it out is one option. Keep in mind that if you do a lot of heating first - it might get too hard to drill.

For large broken bolts - with a cutting torch cutting head- you can torch most of the broken bolt right out. You can buy a special tip for this work - but a standard tip will do - although you might ruin a few. This works best with bolts 5/8" and up . Once most is torched out - you can use a pick or sharp coping chisel to knock out what's left in pieces.

In some cases - as I've mentioned before - we heated the surrounding area quickly until some color just began to show -and then hit it with cold water. This works well if done right - and I've never had a forging or casting gets weakened and crack later. It's a last-resort method - but sometimes works when other attempts fail.

In regard to removing rock-guards for roller replacement? I've seen many people torch out pieces of the rock guards to get clearance to change the rollers and then - weld the pieces back in. Certainly not something you want to do to a collector's machine. But - I've seen it done many times - and it can be a useful time saver for a user-only machine if appearance is a non-issue. Of course, very often the roller bolts don't want to come out either.

[stmftr395]

I have had great succes in removing broken bolts by welding a nut to the remaining bolt(through the center). It takes a little welding skill to weld through the nut to the bolt. If using DC stick welding rod I recomend 3/32" 6010. For AC stick applications use 3/32" 6011 or 6013. I use the TIG welding process. This method works best if there is some of the bolt left above the suface, but will work if the bolt is broke off flush. If the bolt is broke off below the surface this may not be the correct choice. I have had great luck removing broken bolts this way. I believe the heat from the welding helps to free up the threads. The only bolts that did surcome were the ones in the ones in the mounting brackets for the rear under carriage support bar on my 1010 . All eight had been broken off prior to my ownership and I wound up having to drill out all of them. The bolts were very hard steel and the welds would crack and break while trying to turn out the bolts. This is just one suggestion of many I'm sure you will get. Mark

[Ray III]

My dad has Extractalloy brand welding rods for removing broken bolts. I've seen him remove many that were a good ways below the surface. Not sure what's in them but they hang on to that bolt pretty good.

He has found it unnecessary to use heat as the bolt is contracted from the heat of welding and turns easier afterward.

[Lavoy]

Exactly sounds like a rod I have used in the past, Supermissleweld, or HighAlloy 500. There are a high elongation stainless steel rod. They work excellent if you have to pull out a broken bolt that is well below the surface, I have burned a lot of pounds of them. They were quite pricey the last time I got some, I would imagine more so now.
Lavoy

[jac]

Get yourself a stud remover that attaches to your ratchet wrench. Heat the bolt cherry red, let it cool some and then use the stud remover. This worked great for me when I snapped off ALL my bottom roller bolts.

If that does not work, then you can weld on a nut and try to remove it that way.

[robotmaker]

well, I didn't snap off ALL my roller bolts, but daggum close. I had 11 total to remove on the right side, and have not yet begun to get to the left. So far, what I have done is to screw on a nut to a partial sticking out bolt, then plug weld it. I got all but 3 left to do now and have only spent all of today on them. I am having trouble with these last 3. They are all broken off below the surface. Using my MIG welder, I have tried building up a nub on the bolt until it gets down below the surface (I am doing this upside down since they are roller and rock guard bolts) and then using a small magnet, holding a nut up to the nub and trying to plug weld it on. Now when I try to remove it by gently rocking it back and forth between tighten and loosen, it just twists it off and what is left behind looks like it has crystalized at the weld joint. I have flooded it with CRC "Screwloose" penetrant and rust disolver after waiting for it to cool a bit hoping it will help, but... am not having much success. This worked for 2 that were broken off below the surface by the way, but they must not have been rusted into the threads as bad as these last three. How can I fix this crystalization that is occurring? Just heat the poop out of them?

[Stretch]

I have had pretty good success when the bolt is recessed by drilling down through the center, then I would plug weld the hole starting at bottom and build up. Build up high enough to weld a nut on what is sticking out. Let the whole thing cool and you should be able to back the broken bolt out.
By welding up through the center it causes the bolt to shrink. I have used this process on a lot of bearing races that are in blind cavities also. You just run a bead of weld around the race and it will darn near fall out.
Hope this helps
Stretch

[Ray III]

I have used this process on a lot of bearing races that are in blind cavities also. You just run a bead of weld around the race and it will darn near fall out.

That's a great trick, thanks for sharing.