So, what was supposed to be an easy job is turning into a nightmare. The old CAT 225 needed several rollers. When trying to remove some of the bolts, several were eroded on the shank and broke leaving about 1/4" of bolt sticking out of the carbody. The thread length in the carbody is only about 3/4" and are blind holes. We were working to try and weld something to the remaining bolt shank to get them out but proving difficult. Drill will SUCK. Just curious if anyone has other ideas I have not thought of yet?????
Sounds like you've got yourself a job & half - Good luck with the welding With a similar job - I soaked the seized area with WD40 ; applied heat then used an easyout via drilled hole to extract the stubs Also try giving the studs a good smack with a hammer to break the corrosion surface tension before attempting to extract Good luck
Yeah . . . fastline. This is a pretty common problem only they often break off flush. If you have some bolt sticking out you are way in front, preserve it at all costs. First thing is to clean up the protuding bolt with a wire brush to get it nice and bright for welding. While you are at it clean the underface of the trackframe. Next get (or make) a flat washer that will fit over the broken bolt and hard up against the trackframe. You will need a good operator with high amps on a 2.5mm electrode to get a good dab, dab, dab, full penetration weld on there and weld the washer to the bolt. This weld needs to be the real deal no gorilla snot or lumps. Grind it back untill you get it as good as possible. Next weld a suitable sized large nut to the flat washer, go home and have a beer and let the whole thing cool back to ambient overnight. With a bit of luck it will turn out with a shifter. The heat of welding with high amps to the bolt seems to break the rust and most times they come out pretty easy . . . provided you have blind holes. Some machines don't which is okay provided the correct bolts are fitted with zero protusion. Don't dispair if at first you fail. Try it again only this time heat the track frame adjacent to the bolt . . . a few strategic whacks with a four pound hammer never go astray All the best with it. Cheers.
Nice instructions Scrub Puller - I especially like the washer up against the sub frame bit (and going home to have a beer) - could have benefited from that gem with my recent efforts Cheers
Nice instructions Scrub Puller - I especially like the washer up against the sub frame bit (and going home to have a beer) - could have benefited from that gem with my recent efforts Cheers
If that doesn't get 'er go home and have another beer .......... but it ought to based on my past experience.
spot on, its all about technique, once you have done afew you get a feel for the job another little trick which works is work the bolt back and forth (tighten then loosen) to help work it free, we had a heap of gear working in and around a nickle mine/plant around tailing dams on conveyors the only way we got them out was to subby it out to the welders and get them to spark eroad them out don't forget the antiseize on the new bolts!
I don't think the manual calls for anti-sieze on those bolts, so if you do use copper-based anti-seize then drop the amount of torque on your torque wrench by about 1/3 to take account of the greatly reduced friction caused by the anti-seize. A good plan is to completely fill the hole in the roller where the bolt goes with anti-seize - it will prevent ingress of water and reduce the chance of corrosion on the new bolts. Also a dab of anti-seize between the bolt head and the washer is a good trick.
I checked the manual. No anti-seize called for. Specified torque on the bolts is 225 ft. lbs. Suggest you reduce that to about 150-160 if you put copper-based anti-seize on them and about 180-190 if you use a graphite-based anti-seize.
If that dosent work get a small no very small tourch, someone with good eyes,a coffee can of water (to cool tourch) a hammer & punch to remove slag, and cut /melt them out leaving the threads like cutting a nut off a bolt.Then clean them up with a tap. I thought my buddy was nuts when he said break thoses bolts off so we can get started but seeing was beliveing, he made it look so easy, also handy on dayton wheel studs. Hope this Helps
good advise, everyone Not done this on a 225, but done it on other older machines go just above the thickness of the bottom of the rail, cut a square hole about 2"x2" take a torch and blow the bolt out now you can put a bolt and self locking nut in there, use good bolts Ive drilled/ soaked/easy outed/broke off easy outs, then you dont want to drill easy outs, days later, blowed a hole in the under carriage rail and put bolts and nuts in there
I use Anti-seize (teflon stuff) on everything under carrige related! Last time I did track chains the pad bolts all came out just fine after 9000hrs of use. I swear by the stuff.
I wouldn't disagree with you and I would also use anti-seize every time, however .......... you need to make sure you don't over-tighten the bolts. If you use the torque figures in the service manual (which are without putting anti-seize on the bolts) but you put anti-seize on them you are without doubt over-tightening them.
I like the method with the washer. It is new to me, as my guys and I have usually just tried to weld a nut to what is left. It is very hard to get that to work, as hard as it is to weld inside the nut. Using the washer first should make life easier. Many thanks for that.
Yair . . . To take the washer method further. If studs are broken flush in (say) an engine block you can turn (or drill) a relief on the I/D of a slightly undersized centre hole in a made up washer to make it easier to get that first weld in there with the maximum amount of meat. The ideal situation is of course to use the TIG. Back in the days when my eyes were good I used to routinely remove studs right down to quarter inch using this technique. Slightly O/T but the other day I showed a bloke a little wrinkle as to how to undo inner diagonal brace trunnions of an old D7. The bolt heads were too worn to take a socket or ring spanner but I showed him how to heat them cherry red with the oxy and flatten with a decent hammer untill they fitted the next size or two up or even metric. Its the same deal with the heat. it seems to transfer through and crack the rust and the pounding seems to loosen things . . . in fact if you look closely after everything has cooled you will often see a few thou. clearance beneath the bolt head. You need to leave the components cool out of course and it will work most any where you can get at the bolt head and hit it square. It's bloody good to be able to pass on little bits and pieces that may be able to help someone somewhere. Cheers.
We got this pig skinned! 8 bolt broke, all 8 extracted. The real short ones, we used washers and welded a nut to them. The rest we just welded the nut. smacked the **** out of them the break them loose and I am certain the heat from the MIG helped is out. A couple bolts were near flush but we put the full power of the mig to them and got a nice bond to the washer and was super easy sailing. However, dry conditions, wind, dead grass etc, made for some interesting times. thanks for the ideas guys!!
Yair . . . Good one fastline. It's good to hear of success!! Cheers.
I'm surprised you didn't have a grease fire also ........... that's what usually happens when you're trying to get broken bolts out .........
one of my more embarissing moments was catching a machine on fire doing some welding on it on my lonesome, of all things a new fire extinguisher bracket lol
Well, regarding the fires, we only had one small grass fire under the machine but since I was spotting, I quickly got on it, snuffed it, and we doused the place and got water and suppression equipment on the ready. Not looking to lose an excavator just yet. We washed the machine a while back but over 30yrs of grime does not all come off in one wash. Machine also still has a couple leaks so I was nervous. Oil soaked ground, dry grass, wind, sparks..What else do you need for suspense?
machine sitting out in an open paddock in a lightning storm overhead'll do it
Been there done that on a Deere 450 that was under water, all of the carbody to track frame bolts needed to be replaced, and most were broken. I got lucky on a few welding another bolt to the broken part and spinning them out with lots of heat and wax. The others were real bastards and needed to be "surgically" removed with a torch and the air chisel. I am still pissed the guy bought this machine sight unseen, it is a nightmare.
Hello there, A question, will a propane torch work to get the bolt hot enough, and will a small tig welder work on the stud that is broke ? Or how big a TIG welder do i need, or is a torch better to heat and weld, Thanks.
Yair . . . wosama931b. I think the secret is getting the heat concentrated into the broken bolt so that it expands and contracts at a different rate to the surrounding metal. I believe the more difuse heat of a propane torch would not have the same effect. I used a 180amp TIG and 316 fillerwire. It was a long time ago and I'm guessing but propably on anything over (say) 5/8 it would have been flat out and backed off a bit for the smaller stuff. The more heat you can get in there the better and the beauty of the TIG is you can build up a perfect weld in there. Cheers.
Yeh, its all about getting heat into the right place quickly, propane torch won't be as effective, the aim is to either heat the stud/bolt/broken bit without heating the parent metal then to let the stud/bolt/broken bit to cool before trying to move it OR to heat the parent metal without heating the stud/bolt/broken bit AND attempting to move it WHILE the parent metal is still hot (not always possible) if your planning to weld a nut onto the remaining stud/bolt/broken bit that may get enough heat down the shank of the broken bit to do the job but i would let it cool with water or silicon spray (works better than crc as it won't evapourate off) to cool the stud after welding and them use the propane torch the try and heat the parent metal while you work the stud/bolt/broken bit (give it a solid wack with the hammer first) Its more about technique and trying to work out the reasons for the broken bolt before you can attempt to remove it IMO, if the bolt had sheared it's alot easier to get out, a hammer and chisel or LH drill bits and air drill might spin it out, but 99/100 times lower track bolts are seized in and broken and/or corroded which are alot harder to remove
Thanks For the Info on the bolts, I think that i am understanding the process, I watched a guy increase the BTU on a torch on u tube, The temp was the same but he increased the BTU's, Its a hard spot to get to, I have always wanted a torch, now i have no excuse not to purchase one, Thanks again for the knowledge.
I have the same problem except my bolts are flush so not much welding opportunity. does anyone know why these things are designed this way? surely it would be better to have the hole drilled right though and have a lock nut on the other end? that way any sheared bolt would fall out or could be hammered out easily. i cannot agree with "lack of strength" arguments because im sure a stronger bolt could be used, a thicker plate could be used. i hate poor design. we are clever enough as humans to design amazing things, stuff like this should not be happening. they know the environment these machines operate in and they cant abused so why not make it easier to fix?
All of ours were pretty much broke flush. simply sacrifice a nut and well the center in which bonds the but to the sheared bolt and grab a wrench. From our experience, beat the hell out of the bolt before welding so you jar it loose and the heat of the weld helps break things loose. We went like 10 for 10 with this. Does not get much easier...
can i do the welding with a normal arc welder? i have a dc inverter welder not got a mig or tig. im not brilliant at welding but i could probably manage this. should i use wd40 first? what other tips do you have? thanks
Yair . . . viper If you were able to weld nuts to ten broken off flush with the surface studs and get them out you are a bloody genius!! And how do you "beat the hell"out of a bolt when it is broken off flush with (say) a track-frame? Most of us live in a very different world and when you get over here you will find that broken studs are never easy. Jack101 . If you read back through this thread you will see how I describe how to weld a washer onto broken off flush bolts and THEN the nut onto the washer. Despite vipers casual assurances it is extremely difficult to work through the bore of a nut and get a meaningful weld onto a broken stud . . . I'm not saying impossible but difficult to do consistantly. If the studs are over 1/2" you can use a stick welder . . . it is always far better with a TIG. Every thing needs to buffed/ground as clean as you can get and do some practice runs to get the amps right on the bench. I find a "dab, dab, chip and clean and wire brush it" technique works best . . . you have to get a good weld in there. I absolutely agree with you about the nut and bolt thing . . . it's much easier just to punch the pieces out. If you are in a situation where an assembly has tapped open ended holes (such as track-frames on a crawler) it is vital on re-assembly that the correct length bolts are fitted . . . even the correct part number may not be the correct length. No threads should protude and idealy the bolt should be one thread down inside. If threads are exposed they are subject to corrosion and will gall up and lock the thread when you try to get the bolt out later. When dismantling rusty machinery it can make life easier if you cut all the threads off flush with the nuts and even grind the nut a little so you can see the outline of the bolt. My pet peeve is over length cutting edge bolts . . . going off topic now, better stop the rant. Cheers.
thanks for that: the bolts are M16 so just under 3/4" what size should the washer be in diameter? smaller than the bolt or same size or bigger? the bolts are broken flush. im glad you agree with me on the bolt through design but most other people have said that it wouldnt be strong enough, what do you think? can you explain again which way the bolt should be? nut closer to the ground or bolt head closer to the ground?
Yair . . . jack101 .The bore or hole through the washer should be slightly smaller than the diameter of the broken stud . . . this is to protect the thread. Go to some trouble to hold and position the washer . . . I have even resorted to holding in place with silicone type goo, I was working overhead though . . . much easier under favourable conditions. Persevere if it doesn't work the first time. The biggest problem will be if you have exposed corroded threads as I mentioned in my post. I must say though that the concentrated heat of the welding seems to cause some of this corrosion/rust to spall off . . . as mentioned by viper the judicious use of a hammer might be of some help If the bolt locks up due to that problem you pretty much have no options but to drill the darn thing out. On a sixteen mill. bolt a good bloke on the oxy could blow it out if it is getatable . . . still involves drilling a small hole through first and then some picking and fine chisel work to clean the threads out before running in the tap. I think the orientation of the bolt head up or down depends on the application, it doesn't really matter, I suppose protecting the nut and thread from damage is a consideration. As I said these things are never "easy" although if you can perfect your "weld on washer" technique you can have a pleasant surprise sometimes and shout yourself a beer! All the best with it. Cheers.
Hi, jack101, I fix a couple broken track bolts by using an off set cheap harbor freight drill to get a small hole through, then using another to get a little bigger hole. Then fire up a cutting torch, stick the torch in the hole and let the cut make the hole bigger, after a couple times it should be clear enough to clean out the threads. Its not easy and does take some time and your gona get dirty, good luck, sam.