One of the bearings in the pulley assembly of the y-axis belt broke. The bearings proved too difficult for me to remove without damaging the pulley. Needing an out-of-warranty replacement (search on Amazon B07QFL7VS4), shipping times were long. While waiting for the new part, I whipped this up. I ordered the replacement bearings on Amazon. 4mm ID; 8mm OD; 3mm Bore Height. To find the exact bearings that I ordered (search B082PPQ286 on Amazon). You may need to cut away any elephant's foot, and use a vice to press-fit. The Prusa MK2s that I printed these on is very dialed in: if your printer isn't, you may need to adjust the x and y dimensions to achieve a good fit (don't modify the z dimension). Print with 100% infill with supports. Good luck!
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