Technical What your thoughts on coolant additives ?

The reason why products like Water Wetter, and 40-below are largely ineffective when used with automotive coolant is that factory mixed automotive coolant already has in it an optimized surfactant package.

You cannot infinitely reduce the surface tension of water. If you could, these products would be sold in half-gallon jugs, and not half-pint bottles.

If your cooling system is on the border of boiling over, and products such as these keep it in check, then you cooling system has problems that you need to fix, permanently.

 

My roadster has run hot since I built it. I have tried WW and every other cooling additive out there . Nothing ever worked . Not saying that it doesn’t work in certain situations. But I should add this car has never puked coolant out of the overflow ever. 60,000 miles so far .If it ain’t boiling over drive it ‼️‼️ Just my two cents ‼️

 

I'm using RMI-25, someone on the Hamb recommended it. Supposed to run cooler, clean, inhibit corrosion, lubricate, cure baldness and some other stuff. I don't know if it works yet.

 

Think of it this way: the Water Wetter or similar product help the heat transfer. But just as it helps to remove heat out of the radiator, it also removes more heat from the engine. So if your cooling system does not have any extra capacity, it can't utilize the extra heat transfer. Your cooling system is undersized and is the real cause of the problem.