There’s a Facebook group called “IH 3 and 4 cylinder tractors” lads on there are very knowledgable and will surely be able to help you. Has your steering got heavy? I would think it might be your priority valve that’s worn. It’s located under the seat, a small unit with 4 pipes coming out of it. There’s also a valve on the filter housing, think it’s a 17mm head. Open it and valve should slide up and down freely, sometimes they get stuck and need cleaning with very fine sandpaper.
Have a similar problem with hitch lock on mine when it comes to locking, it’ll lock the hitch on one side and not the other. I have to play around with the draft control and that seems to allow hitch to lock, maybe try the same when your trying to unlock it
