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.
Of the four cars I’ve worked on in the last month that came in with an overheating concern, one was due to blown hoses at the junction to the heater core, one was due to improper bleeding after a radiator replacement, and two were due to stuck thermostats.
If this “mechanic” has never seen a stuck thermostat cause overheating, then I seriously doubt his 10 years of experience is doing much more than oil changes and pad slaps in the AutoZone parking lot. I’d cross him off the list of people to learn things from. He’s a hack.
In the 6 years of my experience, over 12000 cars went through our shop.
Not a single thermostat stuck closed.
As I prior tech for 40 … 2 cents here …seems to me newer thermostats are fail safe …over heat once and then slightly stays open …I haven’t seen stuck closed in seems like 10 years .