I've had mine bind at any position along the Y axis. It can jam so hard as to stall the power drive, and be extremely hard to turn by hand. Or, one time, back when I still "gently snugged" the screw as the manual recommends, the screw loosened enough that the top heavy Y xis nut flopped over and completely out of its driven slot. One thing I have not yet tried is getting a replacement nut retainer screw with a slug of nylon embedded in it to lock it in place, similar to the upgrade screws LMS sells so you don't need locking nuts on your gib screws (those work very well!). I've had trouble finding such screws, because I don't know what the industry calls them, so descriptive searches lead nowhere.Agreed, this is when mine binds, in the middle of a job but it’s only when the Y-axis is almost at its end. Speaking of, can you post a picture of your spacer ?
I've posted a drawing image of it earlier in the thread in post # 20 which shows the detail of its construction. It is installed now, so if I took a photo of it, all you are going to see is the top of an aluminum rectangle 0.540" thick, matching the width of the crank bearing support block.
One thing I didn't mention before is that adding such a spacer makes it possible for the saddle carrying the table to move toward you beyond being flush in the front of the base casting. Theoretically you could go further with a wider spacer. But since I have a belt driven power drive on the Y axis crank's shaft boss, I could only go this far without having some things make undesirable contact out in front. The power drive uses micro switches to shut it down at both ends of my chosen allowable travel. And to reiterate, this does not "extend" the travel of the Y axis. It "moves" the same amount of overall travel the screw normally allows, placing it further toward the crank, solely to gain space between the back of the table and the face of the solid column, for my DRO scale mounted there.