There are a few reasons this could be happening. Either the red knob has stripped and is spinning freely around the nut inside of it. Or the threaded rod that feeds up to the control arm has stripped. Both cases will require a replacement part.
The FrontLoader has used two different knobs to determine which one you need look at the threaded rod that the knob is attached to.
If the rod has a tapered end use part number 8880226
If the rod has a blunt or squared off end use part number 8880766
Please click here to contact our support staff, or give us a call at 888-925-4621 M-F from 7 to 4 PT.