Allright, just topped up the coolant.
Its all full now, and this time, yay the thermostat housing is a super tight seal - no leaks. All dried 100%, left it over night.
Ran the car for 15 minutes and warmed it up. Could notice at a certain point the thermostat kicked in and that rubber pipe turned pressurised and got very warm. That's a good sign.
Towards the end of the car sitting there idling for all that time.. Still getting some small bubbles coming up out of the overflow tank, so not sure. Only small and 100% look like air bubbles. Actually those only happened once the thermostat was open. So a fair chance they could just be air trapped within the system escaping once the thermostat had opened up (because the aftermarket thermostats don't have that tiny air hole like the stock Nissan ones have.
Well I hope that's what it was.. Will go and top up the coolant in a sec, and then run it once again and see if the bubbles eventually disappear. Hopefully they will.
They definately seem like different bubbles. These are clearly air bubbles coming out from the overflow line and passing up through the coolant and venting out the top. Where as before it was like the coolant was just sitting there boiling kind of thing.
I am predicting that before the thermostat was shot, causing the overheating and therefore boiling type bubbles.
Now that its all been replaced, this is just air bubbles trapped inside, being released...
Will confirm!
