I’m not a car guy. I want to be. I’m learning. I learn by making friends with mechanics and absorbing their information. I had a car a few months ago with some overheating issues. (Got it resolved. No water in my coolant at all, using straight concentrate in a brand new, empty radiator, like a dingus. 🤦🏼♂️) But before I fixed it, someone said it might have been the thermostat. I asked a mechanic friend of mine about it. (I haven’t known him long.) He told me he’s been a mechanic for right around a decade and has NEVER seen a thermostat issue cause overheating. Is he just totally out of touch? Or did I misunderstand how the cooling system of a vehicle works? Let me know.
As an auto tech of 11 years I wanna say . I pretty much never see stuck closed thermostats . Must have fixed hundreds of overheat issues and never seen but like 2 or 3 stuck closed thermostats . Proabbly seen 2 or 3 dozen stuck open thermostats causing under heat conditions. I replace engines, head gaskets , trans mission assemblies and my current job I’m in this week is studding a 6.0 powerstroke diesel and replacing head hadkets (23 hours repair) . When someone hollers theromast the second they hear a vehicle overheated , really tells me the guy eats paint chips and knows nothing of diagnostics.