Why Does Coolant Level Change?

[99lsguy]

Hey gurus,

Just wondering, had the LS since July 03 and I"m referencing the coolant level:

Always been dead perfect on the full mark, did the coolant flush @ 60K (2 months ago) and set it perfect again. All this time(in 8 months) I never took the LS on a extended trip and the level was always FULL.

Went to the Ozarks two weeks ago (260 mile round trip, and when I got back the coolant was maybe an inch below the ADD mark. Stayed this way for a week, then I didn't drive the LS for about 3 days. Now, the level is back up to the full mark.........

So, what's happening???

99

[SKperformance]

The rad cap may need to be replaced but it will not always keep the exact same pressure all the time as it ages.

[wwest]

There are two "full" marks on your coolant reservoir, one for cold coolant, and one for HOT coolant. With the engine oerating and fully up to temperature the coolant should be near the higher full mark.

[VMF]

i rememebr some1 had this problem b4 here and it turned out to be a air bubble somewhere inside, another complete flush solved the issue. but if your temp is constant then u have nothin to worry about.

[99lsguy]

Aaahhhh,

The radiator cap may have fluctuations............very interesting....

The temp guage is rock solid - no problems there!

All good points - thanks!

99

[VBdenny]

Mine has always had the exact same condition. I found if you fill it even up to the "full cold" level, it overflows when it is hot. I suspect that the longlife coolant must expand more than regular coolant. Maybe I should have paid more attention in chemistry and physics.

I don't worry about it, and my temp is rock steady always.

denny

[VMF]

liquids dont expand, they evaporate:) the reason why we use those coolant fluids is not only that it has low freezin temp but also coz it has high boiling temp plus their heat capacity is pretty big comparing to regular water.

[Zdeno]

I have exatcly same problem. When the coolant is cold the level is between the cold and hot levels but when it gets hot the coolant go up almost to the cap. I told this to my friend who works for Volvo and he said to me that I have to check if there are some white marks around the coolant tank cap, marks like dry coolant. He said if it will happends that there will be more and more marks from coolant around cap it means that the engine little bit blow the air to the water and I if want the peace on my mind I can go to the service where they have the sensors for smog check and tell them to they open the coolant cap and put the sensor to the tank and they will see.

I didn´t find that the coolant going to out over the cap so I don´t worry about it.