Thank you Singlemalt for explanation on the motorway M6.
Let me give you my modest opinion, for having a Turbo air/air then air to water and having studied a little.
On airr/air before 1996, head gasket on the first Turbo were a classic. Apparently less on the last RR generation. MAye they change something in head gasket quality or cooling.
From 1996, we have air/water with intercooler and close to 400 hp. The air/ water intercooler is really a very high professional quality oe with a huge intercoler all above the admission, private network with electric pump, electric fan, private radiator, private expansion tank with it's own cooling.
Those cars are very powerfull but in my opnion much ready for the high power.
But there are key points :
- engine oil . Myself I put Castrol Edge full synthetic 10 W60 . ( 60 is a high protection and heating resistance when very hot)
- engine coolant : should be replaced by a high quality one that you make your self from concentrate, 50%/ 50%. MAke sure there is no air in the system following Bentely procedure to fill
- turbo coolant ; same remarks, but there is a special procedure to replace it. Otherwise you get air so coolant is very bad. It took me 3 years to find the bst way to bleed it. Interccoler is at the highest level, not expansion tank, this is the problem. Procedure expalined n IETIS is not sufficient . You need to bleed directly ON the Intercooler when engine is warming hot. Otherwise there will be air.
Personnally, I am testing a 30% coolant 70% distilled water mixture to increase the coolant capacity, and keeping freeezing protection at -21°c, ok for France where I leave. Water is a much better cooler than alccol( glycol). You cannot go under this dilution, to preserve all the other chemical and galvanic protection. This particular mixture is only for the turbo cooling, as I remarked when hot the fan is often on.
Some professionals empty and refill with vacuum system, it might be the most simple and reliable but not the only one.
As far as I remember turbo as about 6liters coolant, but when you drain the radiator you can nonly replace 2 kiters, that's why it is important to drain it every 3 years and put high quallity.
- Make sure electric fan on turbo raditor, front right under head lights, is working and sender is informing him turbo coolant is hot. This fan is working very often. Make sure the raditaor is clean too.
- Calorstat/thermostat is a key point. Bryan participated to an excellent article. It looks like the old one UE.....is replaced but another one PG....., which seems to have interesting advantages and be more reliable. It is in this yellow iron, so one main advantage is there is no more galvanic reaction between inox, aluminum, iron, lead.... Brass is neutral and the new calorstat is completely in brass, with no leads securtiies as the previous one.
Allow me to wonder if all this was really OK on your car.
Now, check indeed if your egine coolant expansion tank seal is really in good condition.
Because if this simple seal is leaking, that will explain coolant coming out of the tank with pressure, loss of 1 liter or more coolant, high temperature, lake of coolant.....`
Maybe it's only that ?
Do you have coolant in the oil when you check the level ?
Is your car exhaut giving sign of white smoke with oil and water mixture ?
I insist, make sure your expansion BEHR cap is in good condition, specially the seal inside.
Or maybe your calorsta UE.....is just block ?
In any case, now, you should replace the calorsta because of overheating and lead security might have disappear.
I suggest you put the new one PG.....
Continental R . 1997