Ok, here is a weird one. I have a 2017 259D with 2250hrs on it. Started a few days ago.. Symptoms. 1) about a week ago we were loosing coolant about 1/4 gal per 5 hours, found the cap was loose so figured that was it. 2) After closing the cap, it now shows overheating when the loader is leaning to the right, if it is level or leaning left it is fine. 3) figured it might be a sensor issue so when it was showing 230+ on temp I turned the unit off and opened the back and can hear it boiling above the thermostat. Is it the thermostat that is out? Or do you think it is something else?
Thermostat is great place to start. Is coolant visible in bubble sight glass (or up to filler neck)?
Is the plastic recovery bottle overfilled and is the little sight bubble by the rad cap empty?
Have no clue on the sight glass. The tank never cycled from cold fill since I filled it. So I dont think it is opening. Leads me to thermostat
If leaning the machine changes the temp gauge that much, then the coolant level is more suspect than anything else. If you don't have a clue on the sight glass, I'd definitely confirm proper coolant level.
Do you have a manual for the machine.?