Changing the shear hub on a John Deere MOCO disc mower on a dairy farm in Wisconsin. It hit a rock and sheared a "shear hub." We can see that all are lined up with every other one and the third one from the right hand side is hitting the one next to it. We shut it down right away. It hit against the ones next to it. we got to pull the "turtle" off with a Dewalt impact driver and remove it. This video might be helpful for someone. Things are going easier if they aren't connected to the tractor PTO. The bolts do have Loctite on them but the Dewalt does break them loose. The shear hub is a rectangular piece with teeth on it around a gear in the middle that we can pull off with an impact driver. There is a lock but the shear hub has teeth and is designed to not have all the teeth on it so that it actually will be sure to shear. I'll use a hammer to line it up. We lined it up and are checking to see what it looks like. Here's the shear hub. You can see the teeth are sheared off it. Better to shear the shear hub than the gear. We'll clean off the pieces of the shear hub to make sure they don't get stuck in there. here is the part number. AE71036, it was about $80 to $100. They come with instructions on how to do this. I used to write manuals like that. that's what a good shear hub looks like. They got enough teeth to work but enough to shear so you don't run into a bigger problem. you have to time this to make sure it doesn't run into other discs. There is a timing mark on the gear and the hub and you line up the two marks to make sure they fit right.
(5:08) where he talks about lining up shear hub marks to make sure it fits.