Why will my Case 580K backhoe swing fully right but only halfway to the left?

[Felipe Rances]

I'm working on a 1997 Case 580K backhoe and the swing function is acting strange. The boom will swing all the way to the right, but only about halfway to the left before it stops. Everything else seems to be working normally. I'm trying to figure out if this is a hydraulic issue, a mechanical obstruction, or something in the swing cylinder setup. Looking for ideas on wheer to start troubleshooting before I tear into it.