Today I noticed my coolant is above max level. I checked in the morning when the engine is cold. Coolant color inside is normal and there are no leaks. Level was in between the marker before. Is this normal?

 

 

No. Open the cap when the coolant is cold to see if there is any pressurisation.

Are you sure the car is on level ground each time you check?

4 hours ago, gregoir said:

No. Open the cap when the coolant is cold to see if there is any pressurisation.

Yes, i have done that and the car is on level ground of course.

It's best to check coolant's level with a cold engine.

When the engine is hot, the coolant level can increase slightly, this is why they call the thing you see as expansion chamber.

 

Although, the consensus is usually the coolant level would drop slightly when the engine is hot due to the pressure being apply to prevent it from boiling.

 

 

8 hours ago, toni8b said:

Yes, i have done that and the car is on level ground of course.

So was there any pressurisation  or not?

When was the last time you checked it?

Given the températures in the UK have tripled over the last weeks I would have thought it was normal for the volume of liquid to increase slightly.

 

If the newspapers are to be believed >30°C is pushing the boundaries of human life so imagine what it can do to your coolant?

Out of interest, what does the pressurisation in the expansion tank indicate??

4 hours ago, Wino said:

So was there any pressurisation  or not?

No, I check in the morning when the engine is cold and there is no pressurization.

That's good news.

 

@ Benjaminion Pressurisation when cold may mean something (usually gases) have found their way into the cooling system during engine operation. Never good news.

Cheers Wino, i only ask as the wife's DS3 seems to consume oil (which i have been told is normal for that engine) and now has started to lose coolant with no obvious leak. Will wait for her car to cool down and check the expansion tank.

Keep an eye on any further increase in the level  and any contamination by oil etc.

No pressurisation is encouraging.