AGE candy crane - trolley binding

[DLinkOZ]

Does anyone have any experience with these older 24" candy cranes?  I picked one up super-cheap, along with a larger Greyhound crane (also super-cheap).  This thing is *almost* back up and running - new string on the crane (previous owner simply cut it down when it broke, and it wasn't long enough to travel to the limit switch and close the claws), a little weed eater trimmer line to replace the broken Y axis drive belt O-ring (always ask yourself - What would a redneck do?  And he would NOT pay $30 shipping on a $5 part!), now just this binding issue.  What I'm looking at:

It always moves left to right without issue (towardsplay area from home).  Moving right to left (towards home), however, is a crap shoot.  Sometimes it binds, appears to be at the front of the machine (opposite the drive motors).  If I give it a gentle nudge, it will keep going.  When it does bind, all four nylon wheels bind up and the drive belt O-ring in the back slips across those two wheels.

I've loosened all the hood bolts, and have tried forcing it around a bit while binding, but that hasn't really yielded positive results.  Has anyone else ever seen this problem?