Okay, that sounds like the radiator is partially blocked or the pump has an issue. It doesn't take much to block one, if this has AC a common issue is crud getting between the condenser core and the radiator. That blocks airflow. For that I use an air wand to blow through the cores and clean out the fins. A good strong light can show that type of blockage. The IR thermometer will show internal blockage.
Also do not run any coolant mix stronger than about 60/40 water. It will cause an engine to run hotter. The water is there for heat transfer and the coolant is there to assist with that as well as keep the coolant passages clean and raise the boiling point of the water. However excess coolant doesn't transfer heat as well and can cause a hot engine.
Tuesday, April 30th, 2019 AT 9:28 PM