Recently, I bought a Total Coolelf Auto Supra -37 for my car. It's a 50/50 prediluted and ready to use coolant with PH value of 8.4 (I measured and it was 8.6).
Here is a picture of the product:
The problem is that I googled a lot and found out that the optimal PH value for car cooling system should be between 9.5 - 10.5. I'm somehow confused about why Total didn't obey this rule in this product (PH = 8.4! < 9.5!)
COOLING SYSTEMS - THREE STAR AUTO SERVICE, INC.
My question is that can I increase it's PH value by adding distilled water to it before using it in my car?
Our city's tap water has a PH value of 7.5 and when I added it (Tap Water) to my old coolant it's PH value rose from 8.0 to 8.7! (0.7 higher). But tap water contains minerals which are harmful for the engine and cooling system. So, I decided to add distilled water (instead of tap water) to my newly purchased coolant (Total Coolelf) to increase it's PH. But is this possible?
The boy at the shop told me not to add water to the product because it is premix and ready (supports -37 degrees) but in the area where I live the lowest possible temperature is zero and it never reaches -37 or so! Therefore adding some distilled water to it shouldn't cause any problems. It just changes it's freezing point a little higher (for example from -37 to -25) which is not a problem for me. What is really important for me is the corrosive factor of the coolant and PH value.
Please someone enlighten me about PH and it's optimum range for car's cooling system. What can I do to increase my New Total Coolelf's PH from 8.4 to about 9.5 (Optimal Range) ?