Technics SL-1200 MKII Bearing Problem


I think I have a problem with the bearings on a Technics table I just bought used. The tonearm doesn't swing fluidly. It has a tendency to pull back to a position a little to the left of the arm rest.

The anti-skate seems to be ok. Any thoughts? Is it hard to replace the tonearm?
128x128heyitsmedusty
I thought the anti-skate only pulls in one direction (away from the platter) to counteract the centripetal force of the rotating record? If this is the case, then it should never pull the arm back toward the platter, as it does when I move the arm to the right of the arm rest.
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I took it to a professional, and it's fixed, basically. If I balance the tonearm at zero, set the anti-skate to zero, and then pull the tonearm over to the spindle it still drifts back to the edge of the platter, but much more slowly now.

I guess this is normal?