Subject: Re: V12 Boiling
Dear oakley, this is really a hot topic:
our water is really soft (comes form the black forrest mountains, we never have stains of lime in the kitchen or bathroom), The stains must be something else but I will try next time vinegar. I suspect the hot antifreeze (ethylene glycol plus additives) for the stains. (it may depend on the type of paint, mine could be from the seventies, how do you find the type of paint used ?)
Overheating: I want to emphasize that the temperature of the cooling system always stays low in my car but somewhere in the cylinder head, I assume, there are areas which have become very restricted over the decades by deposits and there is almost no flow. So I get boiling at 70 to 80°C water temperature, if I do not switch the additional electric water pump on.
I do not have an electric fan either, and I agree, it is not needed. I really believe the problem is the restricted flow in the cylinder head. The cure for the moment is my electric water pump, the solution would be cleaning the cylinder heads (acid clean with strong enough citric, formic or acetic acid in hot water. This removed huge amounts of scale from Eckards cylinder heads, I am still pushing on him to publish this)
And may be the impeller of the original pump is coroded so it pumps less, especially at low revs.
Peter