Question about coolant level on 2003 Q45

[infinitiemperor97]

Hello all,

I have a question about my coolant level. I took my car in for an oil change and the tech noted that my coolant was below the MIN line (it was). I filled the coolant up to the halfway point between MIN and MAX when I got home. I went to school the next day and the car had no visible issues, but upon checking the coolant after it had been running it was back to around the same spot just below MIN. I checked it again when cold and same thing. Coolant was flushed last summer when my mechanic replaced the arcane hydraulic water pump these early F50s come with. Car has NEVER overheated and I don't see any leaks. I also don't see any signs of a bad head gasket (milky oil, smoke, overheating). Is this just one of the many weird quirks of these cars? Thanks in advance.

[PapaSmurf2k3]

Try topping it off again. There may have been an air bubble or something that you burped out.
Also, where is the coolant level when the vehicle is hot? If its near the very top of the reservoir, you may be spilling some out of there...

[cbird805]

You should check the coolant level at the radiator cap, not the overflow reservoir. The reservoir will fluctuate depending on whether the thermostat is closed or open. You also need to have adequate coolant in the reservoir, as well. Just don't assume you're good on coolant because your reservoir is full.