Originally Posted by notanotheralfa
Mines the same had it since new 76k fully maintained , i had the impeller changed with the belts so it isnt' that . Its on the original rad and sometimes it seems to lose coolant and sometimes there is still coolant in the overflow tank . No gloop under cap and steam from exhaust on start up but it clears quickly .
car rises to about 80 on the move but just goes over 90 degrees in traffic fans kick in and it drops but today it was nearly 100 and its not hot weather .
No bubbles from tank when i leave it to run cap off ????? Any ideas ? If its a head gasket the car is scrap .
Right let's get this into perspective... If it's getting to 80 on the move and above 90 at stand still is regardless, even with a duff thermostat it will do that....
It's the time it takes to get there is what you need to be paying attention to, not what temperature it actually reaches.
A good, healthy coolant system on either a TS or V6 will reach optimum temperature within 5 miles or 6 minutes of normal driving regardless of outside temperature or season. If it takes any longer than that, then the thermostat isn't operating as it should be.
This is what confuses owners of Alfa's.
A new thermostat will pay for itself within a full tank of fuel mileage by bring back the correct mpg so worth changing if indeed it doesn't reach the right temperature at the right time frame.
Overheating is totally normal if a thermostat isn't operating as the radiator isn't doing it's job and being bypassed via block cooling and recirculation.
Another thing that confuses owners is equilibrium of the coolant system and correct procedure of bleeding the system... Totally pointless trying if the thermostat is defective so check that first....
Then, and only then...
Remove the expansion tank filler cap.
Get the engine up to temp on tick over until the cooling fans kick in.
Turn the interior heater control to hot.
This will let the coolant run through the heater matrix to dispel trapped air in that section of the system.
Looking from the front of the car, look at the radiator top left corner you will see a plastic flat blade bleed screw. Unscrew it carefully and slowly. It takes quite a few turns until it is virtually out. Don't let it drop out though. you will start to notice a dribble in fits and starts at first... Keep topping up the coolant in the mean time until you see the dribble from the bleed screw is constant... Now close the screw and top the coolant up to 1/3rd full on a V6 due to equilibrium of the engine in relation to the position and height of the expansion tank...
Job done, no more overheating, no more trapped air and no more excess fuel mpg...
Easy when you know how
If you need a tutorial on thermostat change too, I can do one for you that a novice can follow