I got underneath my '67 350 Straight and I was making sure all of the larger nuts and bolts were tight and I snapped a 5/8" bolt that secures the reverser to the crossmember on the right side. It's a grade 8 bolt and didn't put much pressure on it at all, so it must have been compromised and/or just barely hanging on. Anyway, the bolt goes from the bottom of the crossmember straight up into the reverser. The bolt is snapped off about 1.5" or so deep, so I can't easily weld a nut on it to remove it. At best, I could try to weld a 7/16" bolt on it (need room so I can get a socket on it), but even that would be difficult to do given how deep it is. I can't just thread a short bolt back into the hole and call it good because only two threads are showing. Drilling it out does not look like it will work because the crossmember would be in the way of the drill. Might be able to do it with a 90 degree drill and a bit the right length, but that's a long way to go with a large bolt on a 90 degree drill. I could pretend I didn't see it and just count on the other two bolts on that side of the crossmember to hold it. One of the remaining bolts goes through the crossmember into the reverser, and the other goes through the frame and the crossmember. I would have to check on these periodically to ensure they don't snap or start backing out. I could try to grind a slot into the snapped off bolt with burr bit on a grinder and then use an impact screwdriver to try to get it moving. I could remove the crossmember and then I'd be able to weld a washer and then a nut to the bolt and remove it, but I don't have any experience doing this, and the crossmember certainly seems like it's holding the machine together. Not sure what bracing and blocking I'd have to do to accomplish that. I could try welding a bead from the crossmember to the reverser on the front and back of the crossmember, but that's welding cast iron to mild steel. I can weld, but I'm far from a pro, and even if I farmed this out, I think it would likely fail and/or possibly crack the reverser housing. Brazing isn't as strong, but that might be an option. Any thoughts? Scott
Do you have or know a "guy" that has a mag drill? If you don't seems like a great excuse to buy one. You would need the chuck adapter so you could use a drill bit, the annular bit wouldn't reach you could mount it in the the square
I do have a mag drill. I'll have to see if I can mount it squarely there and if it will reach. Thanks
I would replace the bolt that is next to it before attempting to remove the broken one. My reason is that it may be on verge of breaking off too. I wouldn't worry about trying save the threads if you are able to drill the broken one out. Put in a longer bolt and put a nut on if, you have room to get one on it. Red Loctite too.
It's a blind hole, so I can't get a nut on it. Thanks
If you can drill it for a big enough ez-out the broken bolt night come out. I drilled a broken bolt and used an ez-out to get a bolt out under a JD355D loader that is similar but newer.
I've had lousy luck with ez-outs in the past, but I'm going to try one again. Thanks
I kind thought it might be. Any chance you could drill through it ? In the photo the bolt that is still there appears to show that it is loose enough to allow some movement. If it is, your drill bit most likely won't be centered on the broken bolt. IMHO of course. As you know a broken bolt drilled out off center creates another problem. Do you have any left hand drill bits ?
I can use the broken end to make a pilot so I drill straight. Thanks
Do you have the chuck adapter to use a regular bit?
Nope. Need to order one. Thanks
Clean the top off with a burr, flatter is better, find some scrap pipe/tube that fits in there and stick weld it to the bolt, pipe wrench it out after you let it sit and heat cycle. Takes some tries first time you do it, might stick the rod a few times on the tube, plus doing it OH. Sometimes it takes a couple goes anyway to get it moving, some light air hammering of the area if possible to shock the bolt can help too.
A few folks mentioned this method in a Facebook forum. I don't have a stick welder at my shop anymore, but I should be able to MIG it. I'm inclined to try drilling it and then an easy out first. If I snap off the easy out, I can still go the welding the pipe route.
Yeah shorter ones you can do with the mig, I'll do it with a flux core gun a lot with the nozzle off too. Drilling through if you can also will let the bolt contract a little bit witch usually helps too.
I have this one Hougen Drill Chucks & Required Drill Spindle Adapters Drill Chucks & Required Drill Spindle Adapters Two sizes of Drill Chucks are available for Hougen Magnetic Drills. The 1/2" Chuck fits Models HMD904, HMD905, HMD917, HMD914. The 5/8" Chuck fits the HMD917 & HMD914 Drill Chucks Part No. Description 10731 1/2" Hougen Chuck with key 10732 1/2"... hougenmagdrills.com
Thanks for the link.
Whatever you do, don’t try and weld or braze cross member to reverser. It’s bolted for a reason. The pipe trick works well, even with a MiG, with the nozzle off, just crank it up. If you can pre-drill a bit before trying, it may help. Being that the bolt just snapped off, you can bet that the cross member was moving enough, the other bolts are compromised but looking at the pic of the broken bolt, it doesn’t look like it was moving. Might have been broken under a shock load. I have done repairs like this using 6011 1/8” cranking up to 200 amps and burn/melt right through the center, while using the pipe method. This heats up the broken bolt and the heating/cooling shrinks it a bit, then I will welding it to the pipe. I have some 1/8” tungsten, I will use in my rod holder first and burn a hole into it.
I'm inclined to try to drill it and use an easy out first. If that fails, I'll try the pipe. I hear you on the brazing; really don't want to go down that road. Thanks for the input.
I would get yourself a good dent in the middle of bolt so your bit don't walk and start small and step up almost to the size of the bolt and then try the easy out, if the easy out doesn't work I would retap it with what ever is left in there, since you have a few threads showing it should create a nice guide for the tap If you can't get the mag in position I would clamp/weld on another piece of metal for you to attach the mag drill to get it where you need it.
All good points. Thanks
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. HeavyEquipmentForums
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'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...
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
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.
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.
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?
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. 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
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
You are right about confusing, lol
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
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.
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
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.
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).
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
They are fully threaded, but I didn't know that! Thanks for the info. Scott
You can take a 3 inch fully threaded bolt and cut with zip disc to 2 inch and it won't cause any problems, but shorten the stretch zone on a bolt with shoulder in a high impact situation and they will break over and over again. This all comes from a Bomalloy technical book that I have that explains it all. Hope it helps Simon C
Have you checked the bolts to the bellhousing on the side frame rail? We couldn't keep those from breaking or backing out on a straight 450.
You're talking about the bolts that go to the reverser mount, right? On the 350 (and I'm assuming the 450 is the same), the reverser is between the engine and the transmission, and it's secured to the frame via the reverser mount with 3/4" bolts that are about 7" long. If so, I've checked them; looks like they've been replaced at some point, but they're holding up for now. Thanks
Always good to change out fatigued bolts while able and replace with Cat bolts or Grade 9 bolts such as Bomalloy or Fedalloy which both can handle a bit more torque and less likely to break. Simon C
I do plan to do that with the bolts that are prone to breakage. I'll check out Bomalloy and Fedalloy. Thanks
Caterpillar bolts are 20% stronger than grade 8 from what I know, and have had good success with over the years. Simon C
I'll check them out, too. Thanks Scott
I think Cat bolts are like unofficial grade 9 bolts. I had a 3/4" grade 12 bolt snap on my tractor that I'm convinced was a defective bolt. The other grade 8 bolt held fine. The bolt held the cab on the top of the axle and the loader frame on the bottom. It's only a 45 HP tractor and I don't do heavy digging or pushing with. Very strange!
Yes sir those are the ones.