Technical water temp goes up when idle but not when driving please help!!!

[flisko]

should the actuall coolant level be between min and max when engine is cold?

 

[fingers99]

Yep. Don't forget, we thought you were overfilling it previously. See what Blu said.

 

[flisko]

i was always filling it to max mark

 

[fingers99]

You was a bad boy. Listen to uncle Blu.

 

[flisko]

he isnt uncle blu, there is only uncle dave

 

[flisko]

strange thing here is, on my first rad, temp gauge was sitting exactly in the middle while driving before it started to leak then it dropped, on the second rad -while driving it was never on the middle, and on this new rad, again below the middle while driving, antifreeze is same, maybe its not 50/50 ratio anymore if that matters, removed water temp sensor and cleaned it but still doesnt reach middle while driving

was holding top hose and looking at the temp gauge to see when thermostat would open, hose got warm when temp gauge was at pic below

 

[fingers99]

That would seem OK.

 

[blu73]

he isnt uncle blu, there is only uncle dave

 

[flisko]

temp gauge wasnt at the middle while driving cuz of too much coolant in the tank
​

so we have come to the final conclusion

if u have changed your water temp sensor, thermostat and radiator and still gauge doesnt sit exactly in the middle while driving let some more coolant out through either one of the bleed screws and the gauge will stay in the middle

 

[flisko]

so its either expansion cap or head gasket that is causing coolant to blow out?

lolololo temp gauge wasnt at the middle while driving cuz of too much coolantin the tank
​

so we have come to the final conclusion

if u have changed your water temp sensor, thermostat and radiator and still gauge doesnt sit exactly in the middle while driving let some more coolant out through either one of the bleed screws and the gauge will stay in the middle

edit to the final conclusion

coolant blew out at the expansion cap cuz of a bad cap and too much antifreeze in the tank, replacing the cap fixed that


just for fun i have put "leaking old rad" to the previous car, added antifreeze and bled it, and what do u know, no leak anywhere

looks like that is how a radiator on a punto dumps excess antifreeze, by leaking it out till it reaches the mark somewhere between min and max

this guide says to fill the coolant tank to max mark, but as far as i have learned, that is incorrect and will cause the illusion that your radiator has suddenly started to leak when infact it is just dumping excess antifreeze