The coolant used in the 206 is a mixture of Glysantin G33 anti-freeze + corrosion inhibitors and water in the ratio of about 50% Glysantin/50% water.. Peugeot now comes out with another Glysantin anti-freeze + corrosion inhibitors, called Glysantin G32-31F. I think both are state of the art products that will allow a longer 5 years/120,000km coolant change. Are the two different, and are they interchangeable? The cooling system will perform better if the coolant mix has more water, say 80% water to 20% Glysantin anti-freeze, as water is a better medium than anti-freeze in getting rid of heat. However, using more water will reduce the coolant mix pH to an acidic state which accelerates corrosion. Distilled water has less contaminants but the trade-off is even lower pH than tap water. The ideal coolant mix pH is alkaline, at 9 to 10. Anti-freeze has a pH of 9.5 to 11 and tap water 8 to 8.2. Distilled water sold in bottles average between 5.3 to 6.1 pH. With these parameters, it is almost impossible to use the ideal 20/80 coolant mix, i.e. you will get a pH of only 8.4 if tap water is used, or a pH of 6.8pH if distilled water is used. Both are below the ideal 9-10 pH. Can you increase the pH with a buffer that is not corrosive to the various metals, rubber and silicone hoses in the cooling system over time? Any thoughts on this?
