volvodude

Hi,

I have a 1998 ES300. The coolant when the car is parked and warm is at the Full line. But when sitting overnight cold, the coolant is at the Low line. Is this normal, or is it low?

Thank you,

Michael

LeX2K

It is normal, coolant expands about 3% when the engine is warm that's why there is an overflow bottle. The radiator cap regulates the flow allowing coolant to go into the reservoir as the engine warms up, then allows coolant to be drawn back in to the radiator as the engine cools. With the engine at operating temperature the radiator cap is sealed which pressurizes and raises the boiling point of the coolant.