Confusing Coolant

[garisyaris]

Hi all
Feel a bit dumb asking this.
(see pics)
I would expect when removing radiator cap when cool, as with other vehicles, the coolant level to be at the top, right under cap. However with my 2012 Yaris, there is always an empty space below the cap, which can filled up with about 50ml of coolant.
Run the car, come back coolant in expansion tank a bit higher as expected. Let sit for 8 hours to cool, coolant level in expansion tank a little lower as expected. All working good. No issues.
Take radiator cap off, and there's that small empty space again under the cap. Is this normal? Is it because the cap is higher than the radiator?
An irritating ocurrance, as I can't understand the reason for this, being a dumb bum.
Any explanation appreciated.
Cheers ... GarisYaris

[BLH]

Is their any coolant in the coolant tank?
It should be on the other end of the tube connected to the neck of the radiator. As showing in your photo.
It has full and add lines on it and the coolant flows through the tube as the radiator warms up and cools down.
I believe what you are seeing is normal. As long as the coolant tank is not empty.

[garisyaris]

Yes

The coolant level in the plastic overflow tank is fine. It varies as it should depending on how hot the motor is. No leaks anywhere.

[bronsin]

If you ever look on the bottom of your hood on the right hand side where the drive belts are and you see colon stains on the bottom of the hood your water pump is leaking.

I agree your situation is normal

[garisyaris]

Hi
Thanks guys. My paranoia flaring up again. I'll sleep tonight :)

Garis