Filtered/deionized water in the cooling sys?

aar0s

Founding Member
Dec 20, 1998
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I have a friend that is big into aquariums, 1 30 gal freshwater 1 50 gal fresh and a 80 gal saltwater. She is a go all out or dont do it kinda gal so she also has a reverse osmosis filtered (like Dassani bottled water)/deionizer to make the ultimate fish tank water. seeing that im at least going to have to drain my rad, might go ahead and replace it, would it hurt to use the deionized water? seems like i read somewhere that it will pull trace metals out of the engine, can anyone tell me different?
 
Deionize Water Misconceptions


WE have an industrial supply of DI water at my work. I have seen it corrode Stainless Steels when left exposed over a period of time. WOuld I use it in my car?? Eh, it's been 22 years with regular distilled water (with a top of of tap) and fine....


Just don't drink it...tastes like ass and might not be biologically pure until you boil it a bit.
 
Like Mike said, you should only be using distilled water. I paid a bunch of money for my radiator and I'm doing exactly what the manufacturer said. Distilled only. And a ground wire from the rad to the battery. I'm thinking they don't want any stay currents going through the rad and it helps to get rid of any static electricity buildup?
 
ok so if i read that link right ya need the minerals in the water to help keep the water from leaching off the internals in the engine, right?
 
ok so if i read that link right ya need the minerals in the water to help keep the water from leaching off the internals in the engine, right?

This pH range is nowhere near acidic enough to cause corrosion to metal, so you do not have to worry about that. In fact, using deionized water is better because it contains fewer salts, which may not be soluble in the resulting antifreeze mixture. If these ions "salt out", they will deposit themselves on the walls of your engine block, thermostat and coolant hoses. This resulting layer insulates the water from the metal that it is supposed to be cooling, which might eventually result in overheating your engine
:shrug: