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Loose Quick Attach

climb.on · 2017-08-27 21:57

My quick attach is loose with all my attachments, but I can't figure out what is worn out. I'd say there is 1/2" to 3/4" (depending on the attachment) of play between the pin and the rectangular hole in the attachment, when engaged. With all the slop I am mangling the pins and the rectangular holes in the attachment. I couldn't even open the quick attach the other night until I did a bunch of filing on the pin (in the dark - fun) because the pins wouldn't retract due to all the dimples and peaning on the pins. The Case replacement parts are spendy and I don't want to just start blindly throwing parts at the problem. Should the tapered part, or the round part, of the pin engage the back of the rectangular hole in the attachment? I could weld a plate on each attachment to make the rectangular hole smaller, or weld a shim on the top of the machine's quick attach mount, so the pins engage deeper into the rectangular hole. Any idea where the problem is here?

Replies35
  1. #1GaryHoff2017-08-28 23:08

    Hard to accurately determine the issue over the internet, but here is a few things I have seen: 1. The top edge of the quick attach is bent out, (on the attachment side). Pretty common on lower grade attachments. 2. The attachment is not a proper fit for your quick attach. Slight differences between who manufactured the attachment. With the pins fully engaged, the taper part of the pin should fit in the hole. The tapers are to help keep the attachment tight to the quick attach, the lever springs help with this. Connect the bucket to the machine, and don't engage the lock pins. Check how much gap is between the bucket and the bottom of the quick attach. Should be minimal amount of gap. Shim or build up as needed. The rectangular hole should also have a slight taper too it, to match the lock pins.

  2. #2climb.on2017-08-28 23:21

    Great. Now that I know how they are supposed to engage, I can go about shimming and adjusting them so they actually do. My pins won't engage with those holes no matter how long they are. If they were 12" long they would just slide through the hole and still have slop in them. Thanks!

  3. #3GaryHoff2017-08-28 23:27

    Best of luck. Post a few before and after pictures of this project.

  4. #4seville0092017-08-30 07:18

    Are the top and bottom pins of the quick attach greased good? If not, need to keep them greased good - world of difference. I was having problems with mine until I realized that. No clue why I didn't think about greasing them to begin with. Hopefully that will fix your issue.

  5. #5climb.on2017-08-30 13:52

    They became hard to operate, and grease took care of that, but the clearance issues remain. Here are some pictures that show what I am talking about. I think it's a combination of the attachments points being wallowed out a bit and the tapered pins being worn.

  6. #6wosama931b2017-08-30 15:20

    You can see the wear , a good welder is what you need . Also check out the springs and pins , good luck .

  7. #7cdm1232017-09-19 21:39

    The springs look compressed, so I would say there is dirt holding them back or a lack of grease.

  8. #8climb.on2017-09-19 22:46

    They are in the locked position in these pictures, so they should be compressed, I believe. The springs probably are worn out too though. Not sure that makes much difference to all the slop in the system though.

  9. #962oliver2017-09-19 22:49

    I would weld a strip on top of the plate where you got your finger sitting to tighten it up. Is that a home made attach plate? Some are made with generous dimensions.

  10. #10Zrock2017-09-20 12:30

    going to follow this one since im having the same issue..

  11. #11Georgia Iron2017-09-24 22:35

    Yep a good welder is correct. I would flip the bucket over and weld a piece bar across the bottom of the slot, put it in tight maybe an 1/8" closer than you would think you need to the pin will lock in and it will have some extra to hold as it wears out. My case attachments do not have slots that are that deep. So it needs to be modified to fit correctly.

  12. #12climb.on2018-04-07 12:57

    Well I finally got around to welding that plate on. I was surprised just how much slop needed to be taken up. It was a pretty easy fix.

  13. #13climb.on2018-04-07 13:06

    Now I'm chasing the next loose connection... The lower pivot pin on the quick attach is pretty sloppy too, but after inspection I'm not sure new bushings and a new pin will fix this one. I pulled a pin and measured everything. The bushings on the boom are ~1.385", the pin is 1.235, but the hole in the quick attach, that has no bushing is a bit wallowed and it measured 1.35". I'm not sure what the specs are supposed to be, but even if I replace the pin and bushing, it seems like there will still be a bunch of play between the new pin and the holes on each side of the quick attach. Any ideas how to take up the play at that location? Are these pins normally greasable? Mine is cross drilled with a zerk in the end. I wonder if the PO added that.

  14. #14DIYDAVE2018-04-07 21:19

    You could have it line bored, and put a bigger pin in, or take an adjustable reamer, and ream out all the holes, and do the same thing. Hand reaming is hard work, and both sets of holes, left and right should be done, to ensure that the old pin don't wear the new one. If you line bore, you can get bushings, and use a new OEM pin...

  15. #15climb.on2018-04-09 14:11

    Line boring looks expensive. Looks like it's the best fix, but maybe not when you the cost is factored in...

  16. #1662oliver2018-04-09 15:08

    Yes, it is not cheap but it will be like new. On the other hand, if this machine is just for home use, grease it lots and it will last you for ages. (Grease it lots either way haha)

  17. #17jacobd2018-04-09 15:22

    I went through the same thing with my 430. Ultimately I ended up hacking out and welding in new pin bosses where they attach to the ear. Unfortunately this won't work for you because yours is all one cast piece that you can't "take apart." My advice is to find someone with a milling machine, or possibly a large lathe, that can bore the holes oversize and press in a bushing. I was going to go this route with mine but I abandoned it once I figured out the dimensions of my pin bosses were exactly the same as a standard size of DOM tubing. Line boring is overkill imo because all the bores don't need to be lined up together, just the pairs on each end so the pins will slide in.

  18. #18DIYDAVE2018-04-09 21:15

    Jacobd, the expense of line boring is the main drawback, I agree. That's why I suggested using an adjustable reamer, I've done it, but it sure takes a lot of time, and is a real PITA, if there are any obstructions, near the hole, that keep you from turning the tap handle all the way around! Here is a picture of an adjustable reamer: https://www.google.com/search?q=adj...AhVtTd8KHdufBtQQ9QEILzAC#imgrc=J1qRuwCWCmm9HM : Some have varying length guide bushings, that make the job easier. You will need a bigger pin, though...

  19. #19climb.on2018-04-09 22:13

    I used an adjustable reamer on a bronze bushing to remove a couple thousands once...this wouldn't be much more than that right? LOL. I think it would take forever to ream enough to accept a bushing. Im sure it can be done, but I'll live with it before I go through that. You think a mag drill would work? Mainly the issue I think would be if I have enough depth to bore through both holes? I could finish with a hand reamer if necessary.

  20. #20DirtyHoe2018-04-14 07:01

    You would not take too much out with the reamer. Just enough to get a round hole, then install a larger pin like Diydave said. Drills don't do well on existing egged holes. Also they have a hard time staying on location, finished hole size can vary, not to mention a poor surface finish. Steve

  21. #2103hdrk2018-04-19 01:14

    I have a Case 580 backhoe that has pins on the bucket that move but have no way to grease. When dealing with the dealer, we could not find anything any different in the parts list. To me this is poor engineering. If a pin is not locked in place in its hole, it should be able to be greased. And I mean LOCKED in place. On our Gehl the Quick attach pins are greaseable in their bushings. and if you don't grease them they will bind, yet they don't spin, they just have a linear force placed on them with every push or back drag. They are proof that just because a pin doesn't turn in its hole, does not mean it does need grease. On our injection molding machines were I used to work, there were pins used like this. They had almost no force on them during the movement of the cylinder but held a large amount of pressure stationary on every cycle - sometimes cycling every 15 seconds 24 hours a day for weeks. They would were out if you did not grease them. I'll get off my box for now. You might consider have the pins drilled in such a way that you could grease the area that is wearing. I have actually done this with a half inch drill to make a hole in the center of the pin and using a v block from Horrible Freight, drill a cross hole. Drill and tap for a grease zerk.

  22. #22DirtyHoe2018-04-28 00:53

    03hdrk, You bring up a good point on the 580. I have a 580C and noticed the same thing. All of the bucket linkage pins are dry with no grease zirks. I would like to know why since the rotate as much as other pins that are greasable. Steve

  23. #23check2018-05-16 13:23

    Attachments fall off my 246 regularly. Heating, hammering and welding to take up the slop I can understand, but why do the pins retract when I curl down? I can see it plain as day and it seems to be designed to do just that. The taper on the ends of the pins force the pins up when there is a side load on them. How to fix?

  24. #24pajibson2018-05-23 13:22

    I used a mag drill and the appropriate sized annular cutter once to resize the bottom bores on a cat MTL once. rigged up an alignment jig with some plumbing fittings, & a length of pipe. It wasnt pretty but it seems to have worked. that was 2 years ago and the machine hasnt worn out the new bushings yet.

  25. #25check2018-05-23 23:15

    Fixed it so I'll answer my own question in case it helps anyone. When the slot in the bottom of the attachment wears, it allows the pin to drop lower which means less spring tension. After I welded the slots back up to original size, the pins have the correct tension and the attachment stays put.

  26. #26BC873G2018-05-24 08:29

    Check, I am curious how you welded the slots back up? A few more details would be appreciated or a picture. Thanks.

  27. #27check2018-05-24 10:00

    Where the pin goes in, the slot on the attachment usually wears a groove on the back (machine side). I just welded a few passes with 7018 to fill the groove and ground it to match the rest. One thing I need to mention is that the springs on the pins are almost bottomed out when you have the correct tension, IMHO.

  28. #28Urbanengineer2026-07-27 08:45

    Resurrecting an old relevant thread. Why does back dragging compress the quick attach pins and loosen up the attachment? Is this a safety issue to save the pins? I notice this issue with my mulcher and my second bucket. This is an issue with American made and Chinese attachment. Consistent issue even holding down the pin engagement switch. View attachment IMG_8062.jpeg Pins disengaged loose fitment in air tilted back. Getting frustrated I can’t back drag with this mulcher or a bucket. This is making property maintenance difficult and I can’t use the mulchers best feature.

  29. #29Urbanengineer2026-07-27 08:57

    Plate mount has wear. I do not have a great photo of it. Is it common to need to weld the machine’s plate?

  30. #30Simon C2026-07-27 12:11

    Think they are often more bent than worn out. Not going to wear out 1/16th of an inch on a plate like that very easily, but dogs not setting properly at bottom is more often the situation. Simon C

  31. #31Urbanengineer2026-07-27 12:27

    What part bends on the plate? I can take a different angle photo to try and help see if I need some work done. Thanks.

  32. #32DDoug2026-07-27 14:32

    You can download the dimensions online, gives you something to check against yours if it's worn. https://wiki.opensourceecology.org/images/b/b1/Universal-attachment-mount-specification-sae_j2513.pdf

  33. #33DIYDAVE2026-07-27 16:52

    Pick up the attachment and shake it a little so it climbs up as high as it will get. Then take a washer or a piece of flat stock and stick it in the lower gap. Get one centered on each side, tack weld in place, disconnect, and then reconnect. If you can still connect, all's good, weld the other side of the washer or flat stock, grind off any excess weld...

  34. #34Simon C2026-07-27 16:57

    Had one bent one a Deere 326D that was changed on warranty, yours may be straight but just worn some, think DIYDAVE's suggestion will tell quickly how much wear you have. Simon C

  35. #35Urbanengineer2026-07-27 19:59

    Makes sense. I’ll measure, but there has got to be at least a 1/2” gap the bottom of plate there when loading down the attachment. Thank you .