General: engine coolant level

[john langrick]

Hi, a quick question re coolant level.

I had a bit of a fright when son borrowed my xc90 my2003 d5 driving about 40 miles.

I did have coolant level issues about 6 months and 3000/miles ago diagnosed to the radiator which was replaced and since then, no issues.

Son returned car saying that the 'coolant low' message displayed a couple of miles from home. I looked at this the following morning and the resevoir was empty and on ignition, red warning and stop engine message displayed.


I refilled to the mark and all appears well. But now very wary. Car in at the indi tomorrow for pressure testing.

I do notice that once the engine warmed and driven a few miles, the level drops about 3cm.

When cold, usually the next morning, releasing the resevoir cap, there is a release of air pressure and the level returns to normal.

I understand that there remains pressure in the system even when cold, but is this normal?

I have had lots of cars in the past and to be honest never had coolant issues so not sure if this is normal operation.

I just wonder if the large radiator pipes have become flexible with age and thy are now expanding under pressure and may need changing.

Any advice would be appreciated.

Many thanks