Combines 2388 rotor speed adjusting threads

I had a similar thing happen on my 1480. Make sure when you use the bar to to turn the sprocket that you turn the belt a little on the pulleys. That seems to help it move a little bit. You may have to run the threads out if you can and clean them off. Keeping them greased helps keep the dirt out too. If the threads are worn down too far they may be jammed and the sprocket or the mating piece on the hub may have to be replaced. My guess is that they are just dirty. More penetrating oil might finally help. Hope this helps.

we have the same problem,our bearings are out on that part the adjust

I got the adjuster to turn the next morning. I left the penatrating oil to do it's thing overnight and worked the threads back and forth with a bar the next morning and it finally let go. Canola dust does funny things sometimes... Thanks for the help.