I have badly warn pin and bushings in the pivot of the swing tower of a 580SM and wanting to know how to replace them?
That hole looks like the the bush had worn all the way through & the parent metal is now worn? Is the new bush loose in the hole?
It's hard to tell if your bores are still good. If the holes for the bushings aren't worn you have to either freeze the new bushings with liquid nitrogen or dry ice to shrink them enough you can pound/press them in and/or heat the frame they fit in. The bushings need to be tight in the frame. If you need to pound the bushing in use a steel plate on top of it. If the holes are worn you have build them up with weld and preferably line bore them. If only a small section is worn you might be able to use a die grinder and flap wheel to carefully grind the weld down. It takes quite a while to grind down but can be done. Hopefully your bores are still good and just need new bushings and pins. I had to rebuild the top pivot on my Cat backhoe. It was worn pretty bad because the bushing turned in the bore. Tricky to weld and I was fortunate it was the right height I could use my drill press and a boring head. I had to bolt the drill press table to the frame to hold it rigid enough. It was a bit of a pain but I didn't have a choice. I couldn't afford $1000 or more for line boring. I have a thread on it on here if you look in the archives. The title is fixing swing pivot on a backhoe.
After the birth of my first son, the doctor looked at Mrs. & just made an involuntary sound, didn't give me confidence. This one is extremely ugly. I saw one on an heirloom Ford, a loving grandson wanted to revive his grandfather's 4500. He used my lathe, made line boring cones. We spent a few evenings TIG welding up the lost cast Steel before the line bore. He built a homemade line bore rig, making several parts on my lathe. After boring, he made a few custom sized bushings & pins , some for now, others for later. You may have caught yours before significant damage got past the expendable bushing. After blocking up so no tension in the joint, pull the pin & move the tractor a foot. You likely need to separate several hoses. Heat the bushings with several methods. After they cool they will drive out easily. New bushing will not be easy. It has to shrink. The bore has to expand. Use heat on the bore, freeze the bushing. Freezer, 0 Degrees: negligible shrinkage. Liquid propane -40F minor shrinkage. Dry Ice, I vaguely recall about -100 degrees F some shrinkage. I've heard varying numbers for liquid nitrogen, 200-300 degrees -F adequate shrink.
Looks like you have everything ready to just replace the bushing. I didn't look close enough at first but it looks like the bushing is still in so you could be in luck if it didn't wear through. If you had a die grinder you could cut a groove not quite all the way through the old bushing and split it with a good whack on a punch to get it out easier.
Welder or acetylene torch is the easiest way to get a bushing out. It won't take a lot. Start by welding three stripes vertical inside the bushing. You can also heat a spot with torch dull red. Let it cool, It drives out with a drift punch.
Welding is the easiest but didn't know if the OP had a welder. Heating with a torch doesn't always work because he heat transfers too fast.
only heating to expand & plastic enough to deform. It'll then cool & shrink smaller than the bore.
Might work OK on large dia. bushings. I tried heating the small bushings that the ball on the steering clutch levers fits in on my track loader. Didn't help but melted some of the factory foam/plastic or whatever Cat puts in unused holes. I put a big tip in the torch (cleaned for a perfect cut)and reached down into the clutch compartments and cut the bushings almost all the way through. I didn't want to wreck the bore because it would be impossible to repair. Once I had a notch 90% through I could pound a chisel on the edge of the bushings and got the bushings to turn and they came out. I could have tried a notch on each side but didn't want to jinx my cutting. The first one I cut went straight through the stop block at the back. It didn't affect anything though. I wish I would have had some liquid nitrogen. Those little bushing took some real good beating with a brass hammer to get in. I probably could have just left the old ones in but figured since the steering clutches were done I might as well put new bushings in.
All the thoughts and ideas are excellent! I'm thinking the warn part on the tractor side dose not have a bushing ? As the bushings are for the hoe swing. Thought I had was to cut the tractor side to except a bushing and perhaps weld it in place? Or am I missing something?
I did find a bushing for the tractor side! So do entend to try your idea to remove it. Looking like it may o warn thew the bushing so may have to fill the void?
Remove the worn out bushing and you will be able to see if and how badly the backhoe frame is damaged. From what I see you may not have any damage yet.
I do agree, unfortunately would seem it has warn past the bushing Will pull it out tomorrow fingers crossed
Looks pretty thin but not worn through. Hope you're lucky.
I'm not familiar with the M model, I'm better informed about K & N models. The lower ear gets a different shaped bushing with a flange to serve as thrust to keep the movable portion of the swing from dropping down. Looks like it has dropped too far, you have wear on the top surface of the top ear. Unless my eyes are lying to me you are still good to replace the bushing on top. Cut as welder Dave suggests, not through, only to get it very hot. I might cut three kerfs 1/2 the thickness. Let it cool, it'll drive out with a drift punch Or press it out with the right tool. Lower bushing is different. It is flanged. Rou want to heat it only with arc welder or heating torch with oxy/acetylene, just enough to color the steel dull red. You'll have to bring it up to remove it. Putting new in is easy if you shrink it far enough. Liquid nitrogen will likely be well worth it if you can get it. Make real sure there are no burrs in the bore. Before freezing, check the fit. Aftermarket bushings are likely to be wrong size. You want an interference fit, just a bit too large for the bore. I've had bushings for 580K fit without shrinking, you DON"T want that! I had bushings for the complex end of the dipper. They should be stepped on the outside, .005" smaller on one end. Aftermarket were tapered, not stepped & 1 was loose in the bore. 6 months later in had moved & I had to repeat the job.
Yeah the bushings need to fit tight so they can't turn or fall down in the bore. You can always use a Loctite retainer on them. Because my bores were not perfect I used Loctite 660. Dry ice on the bushings and heating the bore could work. Check with a welding supply for dry ice chips.
Where I live dry ice is readily available. They sell a styrofoam cooler & sell it by the pound. Liquid nitrogen 2 to 3 multiples as cold F is a better bet. You need a Dewar, a monster thermos. I've seen them advertised used. I will never again attempt a bushing replacement without liquid nitrogen.
I have seen the numbers of dimensions of shrinkage. I won't attempt to recite from memory. Only liquid nitrogen can offer the shrinkage needed to fit proper bushings into factory bores. All other methods call for a gorilla with a 16 LB sledge & plenty of swing room.
It's not always that easy to get liquid nitrogen and could be pricey if you need to get a dewar. Dry ice in addition to heating the bore can work. A large bolt with some thick (1/4" or thicker) washers to pull the bushing in and put pressure on it and then whacking with a hammer could work with the dry ice and/or heating the bore. A hyd. Jack or Porta power could also be adapted. Not sure what tools the OP has access to.
Thanks for the advice unfortunately im to far from any supplier of real cold goodies so I put into butter container filled it with water and in the freezer over night and many swings with my 14lb sludge its it
What ever works. LoL it looks like it went slightly too far. Hopefully you put a steel plate over the bushing to pound it in.