Flail Mower Cutter Shaft bolt issue

[Bunnyblaster]

I got this Mott Flail a couple months ago. I had to replace the bearing that used to sit on this side of the cutter shaft because the old one was totally shot. After I did, I put in the bolt and tightened it, but for the life of me I can't keep it tight! After mowing for a bit with it, the bolt will always come loose.

Anyone ever have this issue? What might keep that thing tight?

thanks

Aaron



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