Why does Engine overheat changed thermostat still overheats no leaks Any suggestions?

If your engine is still overheating after changing the thermostat and there are no leaks, consider checking the coolant level, as low coolant can cause overheating. Additionally, inspect the radiator for blockages or damage, and ensure that the water pump is functioning properly, as a faulty pump can impede coolant circulation. Finally, check for issues with the cooling fans or any obstructions in the airflow to the radiator.