coolant level

Hi guys, my first post following migration from Forum5.

A couple of weeks ago I checked the coolant level on my E39 523i (pre 9/98 M52) & found that the level had risen slightly above the max mark. Today the level was even higher in the expansion tank.
Checks are always made following an overnight stand, there's no sign of overheating with the hidden menu displaying 102-105 degrees even in the current heat wave. The car runs faultlessly, has received both radiator & expansion tank within the past couple of years plus a new thermostat was recently fitted.

I have siphoned the excess coolant back down to the the indicated max level & will observe any changes.

Anything I should be concerned about ?

 

How much did you take out?

 

By my calculation around 150ml.

Thanks for the reply.

 

Monitor it, this could just be a bit of thermal expansion at play as the ambient temps increase.

 

Many thanks for that, appreciate your advice.

 

Just keep an eye it. If the volume keeps increasing it can only be due to air entering the cooling system - possibly signs of head gasket failure. Check the oil filler cap for emulsification.