Broken Bolt - Crossmember to Reverser - John Deere 350 - How to Fix?

[AU.CASE]

Have been here and it is a problem needing a solution, in our case several 1" UNC [grade 10] bolts.

The outcome I noticed is that HT bolts usually don't deform and when we centre drilled the broken stub, then heated the factory thread lock, they all wound out by hand without much resistance at all.

So, hope you have a similar result.

https://heavyequipmentforums.com/threads/1000-hour-service-case-1150d.123781/post-1377607

 

[Simon C]

I always if possible drill a 1/8 or 9/64 hole through the center of it using a piece of tight fitting guide in the hole to be able to drill perfectly straight. I always remind myself that each 1/16 drilled or close to it I need to pull out all the cuttings to prevent snapping off the bit. If I make it all the way through I then shoot some Lloyds Moovit penetrating oil with the tube up into the top side of the broken bolt.
I do that 2-3 times then heat the bolt up about 300 degrees with a propane torch to help the penetrating oil on top to work its way down. I usually wipe the face with brakleen on the end of a screw driver with a rag on it . I have taken out a lot with a piece of tight fitting pipe held in there tight and weld with 7018 in a circle about 1-1/2 revolutions and stop.
Let it cool for 30 seconds and most of the time the pipe can be worked back and forth with a set of vice grips to pull it out.
Had to drill a 980 Wheel loader stump pan and in the end had to with proper set up drill them all out just under the thread size and was able to retap the holes.
It doesn't always work perfectly in the real world. If you could get that piece out of the way a nut welded on would put a lot of heat into the broken piece to help get it out.
Simon C

 

[bulletpruf]

Have been here and it is a problem needing a solution, in our case several 1" UNC [grade 10] bolts.

The outcome I noticed is that HT bolts usually don't deform and when we centre drilled the broken stub, then heated the factory thread lock, they all wound out by hand without much resistance at all.

So, hope you have a similar result.

https://heavyequipmentforums.com/threads/1000-hour-service-case-1150d.123781/post-1377607

I'm hoping for an uneventful removal, but the bolts have been in place for about 59 years or so, so they may be a bit reluctant to depart...

 

[bulletpruf]

I always if possible drill a 1/8 or 9/64 hole through the center of it using a piece of tight fitting guide in the hole to be able to drill perfectly straight. I always remind myself that each 1/16 drilled or close to it I need to pull out all the cuttings to prevent snapping off the bit. If I make it all the way through I then shoot some Lloyds Moovit penetrating oil with the tube up into the top side of the broken bolt.
I do that 2-3 times then heat the bolt up about 300 degrees with a propane torch to help the penetrating oil on top to work its way down. I usually wipe the face with brakleen on the end of a screw driver with a rag on it . I have taken out a lot with a piece of tight fitting pipe held in there tight and weld with 7018 in a circle about 1-1/2 revolutions and stop.
Let it cool for 30 seconds and most of the time the pipe can be worked back and forth with a set of vice grips to pull it out.
Had to drill a 980 Wheel loader stump pan and in the end had to with proper set up drill them all out just under the thread size and was able to retap the holes.
It doesn't always work perfectly in the real world. If you could get that piece out of the way a nut welded on would put a lot of heat into the broken piece to help get it out.
Simon C

I will be using a guide/pilot that fits the hole.

Good point on removing the swarf.

Never heard of Lloyd's Moovit, but I always have plenty of Kroil on hand.

I'll heat the stub before and after drilling.

Thanks for the input.

Scott

 

[oarwhat]

I'm hoping for an uneventful removal, but the bolts have been in place for about 59 years or so, so they may be a bit reluctant to depart...

Those bolts have been replaced at least once. You can some gold on the existing one. We had a straight 450. It broke bolts all the time. Mostly on the frame rail outside of the bell housing. We couldn't keep those from breaking. I would definitely check those. I'd drill before welding. Once you weld you have a very hard time drilling. I hope you have good luck.

 

[bulletpruf]

Those bolts have been replaced at least once. You can some gold on the existing one. We had a straight 450. It broke bolts all the time. Mostly on the frame rail outside of the bell housing. We couldn't keep those from breaking. I would definitely check those. I'd drill before welding. Once you weld you have a very hard time drilling. I hope you have good luck.

Thanks for the input.

 

[bulletpruf]

Spent a while yesterday getting another bolt out - it's a 5" long 5/8" bolt that holds the drawbar crossmember bracket in place.



I was hoping to get it out with left-handed drill bits, but no joy there so I just kept drilling and it came out with a #6 easy out.



Yesterday I also realized the bolt that snapped off 2" deep (i.e., the one pictured at the beginning of the thread) actually goes into a hefty cast iron mount that can be removed. I spent some time trying to remove it, but it's a very tight fit. After I moved it about an inch, it wouldn't budge any more, so I tapped it back into place for now. I ordered some low height hydraulic rams; I think with these I can remove the mount, drill it out on my drill press, and reinstall without too much drama.

As for today, my first task was to reinstall the drawbar crossmember bracket with new Grade 8 bolts and flat washers. Torque spec for 5/8-11 installed dry is 220 ft/lbs, but I stopped at 200 because I didn't want to end up pulling the threads.




Next task was trying to weld a 2.5" piece of 3/8" black iron pipe to the 5/8" bolt that broke off recessed in a hole. The goal was to have enough sticking out so I could turn it with a pipe wrench when it cooled off. Anyway, I was using my Miller 211 MIG but I wasn't able to get a good weld started. Each time, the pipe broke off fairly easily as I was trying to turn it. Surfaces were prepped well and I had a good ground; maybe I wasn't holding my mouth right? Anyway, I took a break after the third try and went on to something else.




I also thought about drilling it out with my right angle drill, but there wasn't enough room. The only way to drill it out is with an extra long drill bit. I did get some 12" drill bits from the jungle site, but I screwed up and got HSS instead of carbon or cobalt, so they won't last long on a hardened Grade 8 bolt. I just ordered some 12" cobalt drill bits just in case I try that route.

I'll re-attack next weekend.

 

[smifwal]

How about putting a nut one size bigger on there and welding it on to what you have sticking out, you will be able to weld the whole center of the hole in the nut to the bolt.

I just looked back, did you get some of the bolt out?

 

[bulletpruf]

How about putting a nut one size bigger on there and welding it on to what you have sticking out, you will be able to weld the whole center of the hole in the nut to the bolt.

The issue was with the weld at the bottom - where the pipe meets the stub. I couldn't get a good weld starter that and it would just break off.

I just looked back, did you get some of the bolt out?

Sorry, it's a bit confusing. I have been working on two different 5/8" snapped bolts. One was snapped flush on the drawbar crossmember bracket and I got that out with an easy out.

The other is the one that's broken off about 1.5" recessed. I haven't gotten it out yet.

Thanks

 

[smifwal]

The issue was with the weld at the bottom - where the pipe meets the stub. I couldn't get a good weld starter that and it would just break off.

The weld broke off, the pipe or part of the bolt?

You were going smaller, I think you should go bigger, 2 small tacks on the edges and full on pool the total inner of the nut

 

[bulletpruf]

The weld broke off, the pipe or part of the bolt?

You were going smaller, I think you should go bigger, 2 small tacks on the edges and full on pool the total inner of the nut

The pipe broke off.

The pipe is the largest that will fit.

Thanks

 

[smifwal]

You are right about confusing, lol

 

[Simon C]

If you could get a 1/8 inch or 9/64 size hole with a guide piece up through the center of the broken recessed hole with a cobalt bit you would have a better chance to get penetrating oil up above the broken stud to help it come loose. I do have some special rod for welding out broken studs but tough in overhead position. But I will say that it starts way better than any 7018 for hooking up the pipe piece you put up there. Remember that you mentioned that you only had a wire feeder. Hope you find a way to get out.
Simon C

 

[bulletpruf]

If you could get a 1/8 inch or 9/64 size hole with a guide piece up through the center of the broken recessed hole with a cobalt bit you would have a better chance to get penetrating oil up above the broken stud to help it come loose. I do have some special rod for welding out broken studs but tough in overhead position. But I will say that it starts way better than any 7018 for hooking up the pipe piece you put up there. Remember that you mentioned that you only had a wire feeder. Hope you find a way to get out.
Simon C

I'd like to get a hole drilled in it so I can spray some Kroil on top of the stub, but based on what came out of the hole, I don't think rust is the issue.

I need to pick up an inverter stick welder.

Thanks

Scott

 

[Welder Dave]

Being overhead makes it especially difficult to get any kind of penetrating oil into the threads. Heat would probably help draw the penetrant up. If you got the broken bolt hot enough from welding might make it a little softer and easier to drill. If you had to Mig weld the bolt with 1 1/2" of wire stick out wouldn't make a very good weld on the bolt or anything for that matter. If you could get a long contact tip and a tapered pipe nozzle to fit inside the pipe would make a much better weld. Over about 5/8" stickout you can't do a very good Mig weld. Flux-core wires typically use longer stickout than Mig.

The specialty rods Simon mentioned would be the best but difficult to use overhead. The flux prevents the weld puddle from fusing to the threads for the bolt. Drilling and EZ- Out might be the only option though.

 

[bulletpruf]

Being overhead makes it especially difficult to get any kind of penetrating oil into the threads. Heat would probably help draw the penetrant up. If you got the broken bolt hot enough from welding might make it a little softer and easier to drill. If you had to Mig weld the bolt with 1 1/2" of wire stick out wouldn't make a very good weld on the bolt or anything for that matter. If you could get a long contact tip and a tapered pipe nozzle to fit inside the pipe would make a much better weld. Over about 5/8" stickout you can't do a very good Mig weld. Flux-core wires typically use longer stickout than Mig.

The specialty rods Simon mentioned would be the best but difficult to use overhead. The flux prevents the weld puddle from fusing to the threads for the bolt. Drilling and EZ- Out might be the only option though.

Thanks for the detailed input. I don't have any experience with welding with that much stickout; glad to hear that it's a very difficult task, and not necessarily operator error.

 

[Simon C]

Will say that they do make some fabulous rods for welding out broken bolts but that is not guaranteed all the time.
Very helpful to have an electronic helmut to help put rod up a pipe at the correct angle.
Simon C

 

[Welder Dave]

Thanks for the detailed input. I don't have any experience with welding with that much stickout; glad to hear that it's a very difficult task, and not necessarily operator error.

Just try welding on some scrap. You'll quickly learn how far the wire can stick out before it just makes a mess with no fusion and an erratic arc. Good Mig weld should sound like bacon frying.

 

[bulletpruf]

Ok, so I got it out, but it took some doing.

I tried to drill the stub yesterday to so I could use an easy out, but I needed long drill bits and I ordered some from Amazon that were cobalt, but they sure acted like HSS, so I was pissing up a rope.

Gave up and then figured I'd try removing the mount again. I put a jack under the reverser to keep things in place and then removed the starter to give myself some more room. Then started tapping the reverser forward, but a 1/2" captive nut on the frame got in the way. Wasn't enough room for a cutoff wheel or a big grinder, to I used a burr bit on a die grinder and a chisel and got the captive nut removed. I'll replace it before I button everything back up.




Then the mount slid out.

Cleaned up the mount and spent a fair bit of time getting it in the drill press vise and all squared up, and then I figured I might as well check to see if it the stub will turn if it get after it with a chisel. There was a burr conveniently located on the stub and lo and behold, it came out with no issues!



Before I reinstalled the mount, I ran a tap through the threads in both bolt holes. One had some issues; threads weren't cut nearly far enough, so took my time, used plenty of cutting oil, and got another inch or so of threads cut.

When I reinstalled it, I realized why it was so damn difficult to remove; it was in backwards. One side of the mount had a bevel in the top so it wasn't get wedged against the frame.

It had been installed with 2" bolts, and those were too short. It needed 2.5" bolts, but I just had 2" and 3" so I cut a few down to size.

Installed with some blue Loctite and tightened it to German torque specs (Guttentite).

 

[Simon C]

Just so you know, if you actually cut a bolt from 3 inch to 2.5 inches and it is a bolt with shouldered non-threaded section, it will be a weak bolt afterwards as you have shortened the stretch zone.
If it was a bolt that was threaded right through to the head it will be perfectly fine.
Have fixed many bolt applications where the bolts kept breaking because the stretch zone was too short.
Simon C