Hi,
If the ignition timing is too far advanced, it can cause the engine to run hotter. However, if you haven't touched it, that shouldn't be the issue.
If you open the radiator cap when it's cold and start it, does the coolant start to flow when the thermostat opens? Also, and don't laugh, pay attention to the lower radiator hose when it starts to overheat (when the radiator cap is installed). Make sure it isn't collapsing.
Let me know.
Joe
Tuesday, March 22nd, 2022 AT 6:33 PM