Car radiator

Just ad coolant until it reaches the top of the radiator. Then make sure the reservoir is at the proper level.

Drive the car until it reaches operating temp (with heater controls set on high). Then let the engine cool all the way down. Check the flluid again, top off until its stable.

The entire system holds somewhere between 2.5 and 4 gallons. Not all of it will drain out when any hose is removed. Be sure to mix what you put in 50 / 50 water and antifreeze. If you've been adding just one or the other, you might want to test the freeze point first, then add whatever it takes to adjust the freeze point to around minus 40 degrees.

Too much water in the mixture will raise the freeze point. Too much antifreeze will also raise the freeze point, (doesn't make sense, does it?), But more importantly, it will reduce the coolant's ability to cool the engine. Antifreeze does not hold as much heat, (BTUs) as water so it is very inefficient at moving heat from the engine to the radiator. That's why we put the water in there.

Caradiodoc

Hi Ernest Clark. Sorry for the double reply. Hope they add a button so we can delete our replies when appropriate.

Caradiodoc

No problem. Sometimes a double reply is needed!