My XD3's left rear axle bolt snapped a few days ago, almost flush with the end of the axle. Although the Subaru/Robin EA175 runs with no issue, the engine compression seems weak. That will be checked out Monday, when the mower goes in for an estimate to have the both rear axle bolts replaced, driveline checked/adjusted/fixed as needed and an oil change.
If the compression is weak, I am guessing it will be more expensive to repair than to buy a new mower. No dealers in my immediate area seem willing to work on the EA175 Subaru, so I hope for no issues to be found engine-wise.