I'm trying hard to buy a new bucket for my Cat 307. I have new pins. I want new bushings, seals, etc. So, I need to know how the bushings are put it ? Can I drive them out with a punch like a wheel bearing race ? Thanks
Driving them out with a simple punch won't be easy and you will likely scar up the insertion bore on the machine. You need to shrink the OD of the worn bushing first before trying to remove it if you want to keep the bore clean and make your life easier. Steel bushings can normally be welded inside the inner bore and allowed to cool. This will shrink the bushing and allow it to be driven out easier. Weld a full circle inside the bushing assuming enough is still left of it to accept a weld bead. Rod type really does not matter as long as you can put down a bead. Sometimes I also use an AirArc, plasma cutter, torches or Sawzall to cut a relief line down the bushing to shrink it. I also custom grind punches to split and curl back the softer bronze bushings or very thin bushings. DO NOT scar up the interior bore of the machine where the bushing is driven into. A cylinder hone will clean up any scale and light high spots prior to installation of new bushings. I usually custom cut bushing driving tools on my lathe for the installation of the new bushings. If you have access to a lathe, do that. Your bushings will be installed cleanly without deformity if you have the correct tools. I normally cut them from solid stock, cut a driving shoulder that will do the actual driving force and center bore it so that I can pull it in with a piece of 5/8 or 3/4 all thread from the other side. This also assures proper alignment when starting the drive in. Weld a nut on the outer end of the all thread so you can drive it in with a sledge if the pulling does not work on its own. Chill the new bushings before trying to insert to reduce the OD and make insertion easier. If liquid nitrogen or dry ice is available, that is safest. Me, I normally use liquid propane as it is usually the only cold stuff I have around the shop. Propane is NOT safe but then neither am I. DO NOT use that anywhere near people, buildings, engines, etc. Use your head before messing with flammables. Maybe if you need some bushing practice you can help me with the Menzi next winter! I've forgotten how many bushings go in this thing but I did replace about 12-15 on one front steering knuckle this past spring. That did not include the front or rear of the leg. It likely has well over 100 replaceable bushings, mostly bronze.
Thanks, Treemuncher. I was afraid of that. Maybe I'll pay someone ? My Bombardier Muskeg has 16 wheels with 2 races/bearings in each so I'm pretty darn good at changing those !!
Pixie, treemuncher is dead right. Bushings can be a kind of easy job with the right tools, and one of the most miserable there is without...
I use the house freezer . Not nearly cold as I would like but it does help especially to get a good start to keep things square . I often open my delivery of parts and pick out the bits for the freezer including bearings,bushes large lip seals and if I am using a driver /dolly ,I lob that in aswell .
Funny you should ask. I just went through it on a Case 580K backhoe. Getting them out is easy. As mentioned, weld, acetylene torch, plasma. Your goal is heat the old bushing red hot. It'll try to expand, but has nowhere to expand. It crushes while soft, as it cools it shrinks. Almost any tool will work to remove. Liquid nitrogen at -194 F is the best way. Dry ice may be more readily available, It is 100 degrees warmer than liquid nitrogen. Have tooling READY. Take the time to make a driver the right size. A big boy with a big hammer is a must as a helper.
I always thought you welded a line the length of the bushing, axially, not around the circumference. Just like if you were going to blow it out with a torch. If you just heat a strip the length that you would cut, that section shrinking will be enough to get it to come out easy.
I think welding can work either way. I did final drives on a smaller Deere track loader and just ran a quick Mig bead around the inside of the bearing races and they fell out.
I have had luck doing either to free up bushings. Steel it seems to work good to just weld in a couple places and with brass/bronze just heating till a few spots start to puddle then let cool and usually tap or pull out easy. For installing bushings that need to be set to a specific depth to allow room for seals I always made a puller plate with a flange so it would stop right where I wanted it to. Without the flange seems like they always wanted to jump at the last second and go past where they needed to be.
Hi guys,any suggestions on removing old bushings if I do not have a welder? Will a sawzall cut a groove the length of the bushing? thanks
Most original bushings are very hard, I don't think a sawzall is going to help. Borrow or rent oxy acetylene torch, hire a mobile welder. Heat is really the best way to loosen them up.
Depending on the size you might be able to cut them with a cutting wheel on a die grinder.
That would be my choice. I can easily cut a groove without cutting into the bucket. A Sawzall with a carbide or diamond blade could possibly work also for small bores. But i would have better control with a cutting wheel as WD says.
I guess if you really had to you could use a carbide burr in a die grinder. It would be slow going though.
Thanks guys, I will try a cutting wheel, as long as I can find one with a small enough diameter to fit inside full length of the bushing
I have welded out quite a few bushings and bearing races over the years. I always use some 120,000 pound stainless rod sized 3/32 or 1/8 and weld the bushing in circumference to shrink it. Stainless rod can leave nasty spatter beads, but I deal with that by starting a torch with only the carburizing flame going and coat the whole area with black carbon. Then I wipe off what needs to be welded with a rag with a tiny amount of breakleen to make weld area carbon free. Weld will not stick to carbon. Stainless rods tend to shrink the bushing more. I am talking for steel bushings, Bronze bushings use arc-air. Some bushing have fallen out as soon as I flipped over. Carbon trick works very well for preventing weld spatter. Simon C
Having been in the business of line boring and fitting and removing bearings for 36 years I can say its not rocket science. With a steel bushing a couple of runs of weld around the inside will shrink it out. I prefer to run a melt line through with a torch which is easier and not as messy. For brass or bronze a melt line through and it will fall out. For small bushings you can press,freeze or machine up a dolly and hammer them in. For larger bushes I use liquid nitrogen.
I've personally never had any luck with just putting them in a regular freezer. A proper bearing freezer is dang handy though.
The bushings for the clutch arms in the steering cases on my 931B were pretty limited on removal. Had to cut them most of the way through with a torch on opposite sides and then pound them with a chisel. Should have just left them.
I found that a dremel cutoff wheel will make a nice relief cut on the bushing, but the problem is it will only go in so far.I made a few cuts around the circumference of the bushing and chipped out the pieces with a chisel. Slow work,and not the easiest.I got fed up with doing it that way so I flipped the stabilizer on its side and used the original pin to hammer out the bushing.I flipped it again and did the same thing on the other side, which by the way, is not the same size bushing as the first one.Slightly shorter in length. welding a bead sounds like the best way to go but thats a skill I have never learned.It may be time,,,,
A weld inside a bushing doesn't need to be anything special, just want to get the heat into it.
I should probably look into buying a welder and start learning how to use it. If I am going to kee replacing bushings on this machine, I will surely benefit from it.
It could even be a bunch of 2 or 3 second tacks if you were worried about burning through.
When you're ready to look at welders, post it on here and we can help you make a good decision on what welder would best suit your needs and budget.
its the proper use and handling of the unit that seems intimidating to me,,seems like there is a lot to know just to do the simplest weld job
The welder has a lot to do about it I think. I had a low end sears years ago I couldn't do a thing with then years later I bought a Miller 251bobcat now it seems I'm a pro it's like night and day
thanks guys, I will start doing dome research
Having a better welder makes the learning curve 1000 times easier. It never made sense to me that people will buy expensive vehicles and tools but when it came to a welder they would cheap out. A cheap welder is more frustrating than anything when you're trying to learn.
That's the truth. I know
I could show you how to weld inside a bushing using 7104 rod without a helmet.....
7104 rod? Need to learn how to weld before you try to take short cuts. New welders don't realize they are getting flashed until it's too late. The natural act to close your eye's isn't automatic. It comes with experience.
This is kind of related. I have a friend that has a New Holland skid steer. The bucket mounting plate has a pin on both sides of it which is tapered and goes into the arm and is held in with a bolt. The pins might also be pressed in, I guess from the factory. On one side the pin snapped off at the arm, which is the fat side of the taper. They are put in place from the inside of the arms. So the mounting plate is right in why. The only way to get the mounting plate off would be to remove the whole thing which has 2 hydraulic cylinders and the good pin on the other side of the arm. I first thought it would be easy to knock the good pin in and get the plate to rotate out of the way by removing the bolt then using the hydraulics to move the bucket attachment plate up to give me room to work on the broke side. After spending some time i realized that I was going to either need to cut the good pin in half or not get it out. He had bought only one pin/ bushing special order for about $200. he needed his machine for work but he could not get the broke pin out if the tapered bore. The bucket plate had about 3 inchs of wiggle just enough to get to the pin but not really any room to work from the inside. I tried taking an air hammer and driving into the bushing through the bolt hole side. It would not budge it. Then I tried it with a torch and an airhammer. No go. Ruined my air hammer bit as it ground off going into the threaded hole which was say about 1" all the way through the center. I finally got a small piece of rebar and stuck it through the hole. I bent a welding rod and just could weld it from the inside by going between the bucket mounting plate and the gap. I did not have a good angle. The first try hitting it with a 16 lb sledge it broke the rebar loose from the bushing. So I welded it again and put all the weld i could get to it. Second go 1 good hit and it popped right out and we were able to slide the new bushing pin mount in right through the gap. Thought it was going to be easy ended up taking me about 1 hour.
this might be kind of dumb, but on my Deere 50ZTS which has 45 and 50mm bushings, I used a knockout punch to press those - in fact this one: https://www.amazon.com/TEMCo-Hydraulic-Knockout-Punch-TH0004/dp/B00HJX58HG Actually, reviewing this, my set is a bit different, I don't have the V-shaped cutters in my set. but the press and the backside of the cutters is what's needed anyway. In once case, I pulled the bushing from the far side of the dipper end into the near side bushing by using a threaded rod to continually reset the location of the pull block and just jack the pressure up on the hand-jack, and it pulls the bushing out. it's only 4-ton, so I think for some bigger stuff, it'll be a problem. smaller machines, it's a charm. it was a bit of swearing and all that, but I got 8 of them done in just a few hours. I know it works, and you can be really precise on depth as you want. wouldn't be without it for doing bushing work. it's not designed for this, but wow, it works really well - at least for me on this smaller (10k) machine.