Normal Engine Coolant Temperaturesby Tom LutzenbergerUpdated August 06, 2023
Engine coolant has to remain warm enough to stay fluid so it can be pumped through an engine. Water alone won't work; it will freeze too quickly. Coolant with a 50/50 mix of water and ethylene alcohol (anti-freeze) can function at temperatuares as cold as negative 36 degrees Fahrenheit.
The acceptable range for an engine to run at sits between 195 degrees and 220 degrees Fahrenheit. This assumes a person is running a 50/50 mix of antifreeze and water. At 225 degrees, the mixture will boil but still function up to 265 degrees Fahrenheit if the system is kept closed (that is, you don't remove the radiator cap).
Consequences of Exceeding Ranges
When the car engine gets too hot, the gasoline flowing inside will start to detonate prematurely. This can cause pinging and disturbances in the engine combustion cycle. It can also cause damage to the engine pistons by excessive heat. And it can result in a blown engine head gasket. If temperatures are too cold, the car won't start.
Since 2009 Tom Lutzenberger has written for various websites, covering topics ranging from finance to automotive history. Lutzenberger works in public finance and policy and consults on a variety of analytical services. His education includes a Bachelor of Arts in English and political science from Saint Mary's College and a Master of Business Administration in finance and marketing from California State University, Sacramento.