Anti-freeze is also a coolant. But what really prevents the water from boiling is the Pressure Cap. All modern engines run at about 240 degrees as a normal temp. The pressure is what keeps it from boiling. Don't worry so much about your fan, it's the loss of pressure that allows it to boil. That's why you can't take a cap off a hot engine, it will instantly boil and actually turn to steam. Bad news for the cap remover! Widely different temps, and many other variables are engineered into modern engines and metals and scratching our heads over them just wastes time, they work incredibly well. Ray On Jun 10, 2010, at 9:33 PM, mckanical-marvels@xxxxxxxxxxxxxx wrote: My wife had a Pontiac once, with an aluminum head, that had a 240 degree thermostat! You might say, "Wait a minute. Water boils at 212 degrees". But, we don't use water. Antifreeze is also called "antiboil". I had to ask this question: If I am running at 240 degrees, and the electric cooling fan fails, how many SECONDS do I have until that engine is ruined? [Non-text portions of this message have been removed] ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: Chrysler300-digest@xxxxxxxxxxxxxxx Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/