Why use Glycol based coolant...
Well for many reasons.
Makes one think why every single manufacture of ICE engines on earth supplies them with a glycol coolant.
Not everyone can guarantee, at all times, that the car will be above freezing. Even in parts of Florida, it can get below freezing in the winter. It's a bit of insurance to guarantee yourself you will NOT have problems if you encounter unexpected freezing. Even in a climate controlled garage like you may have, catastrophic weather conditions can cause power failures which will cause heat to go out. Don't argue this topic: it can and has happened repeatedly all over the country and world. I remember just a few winters ago, they were saying that there was snow, and it had snowed in all 50 states, and snow was ON THE GROUND in all 50 states. You cannot predict the weather patterns but you prepare for them.
The only thing you have done with your concoction of RO water and No-Rosion is create your own coolant blend, one that will freeze. The No-Rosion is simply the additive package found in glycol based coolants.
RO water is generally acknowledged to be somewhat "corrosive" because it has an affinity to want to bond with something. This is fairly well known, and the use of it in a car's cooling system with or without a glycol anti-freeze is generally not recommended. There's plenty of information on this for anyone wanting to research it. Plumbers know that you don't use metal pipes or tubes with RO water--only plastic for that reason. I'm a believer in the experts. If they tell me that RO water exhibits some corrosive tendencies, then I'll believe them.
https://www.corrosionpedia.com/definition/984/reverse-osmosis-corrosion-ro-corrosionDe-ionized water is what's recommended all over, and exactly what the manufacturers use when you buy premix coolant. Tap water is available everywhere. So is steam distilled water, and RO water can be had in many places including many people's kitchens if they have an RO system. So with all these different kinds of water available, ask yourself why do the manufacturer's choose de-ionized? I'm not a chemist but they indeed employ chemists who have concluded that de-ionized water is best. I'm not going to question them.
Let's talk cost. Of all the things on a Pagoda this isn't one to break the bank. You need about 2.5 gallons of coolant. The premixed stuff 50/50 is less than $20/gallon. That's the G-48 or the G-05. If you want to mix your own, from concentrate, that is a few dollars more, maybe $24. So you are looking at a $50 fill with pre-mix, somewhat less if you mix your own. Why play chemist with additives?
I think I'll stick with glycol based coolant along with the other 288 million + cars on the road in the USA, and the one(s) recommended for my vehicles.
