Distilled H2O vs Tap H2O in Rad

[landtoy80]

On MythBusters they were boiling tapwater and distilled water. They said that distilled water doesn't boil up when it reaches boiling point like tap water does. Its the other materials in tap water that makes it bubble up when it boils.
They boiled tap water and it bubbled the water up in the microwave.
Then they boiled distilled water and it did nothing untill they added a sugar cube and it boiled over.
They were testing to see if water can explode in the microwave and it can.


This means that distilled water won't make bubbles in the rad when it gets to the boiling point.
Another reason to use distilled water.

 

[firetruck41]

It also will boil with disturbance, ie. driving, engine vibration. In a microwave if you are using a completely clean container with perfectly smooth surfaces you can keep the water from boiling, but if is "disturbed" or the container isn't near perfect it can still boil, IIRC.
I did this unintentionally once, I microwaved some (tap) water in a pyrex measuring cup, but it didn't boilwhile in the microwave as soon as I moved it to pick it up it "fizzed" and boiled, not quite hot enough to explode on me, but I am careful getting liquids out of the microwave now

 

[Scamper]

They said that distilled water doesn't boil up when it reaches boiling point like tap water does. Its the other materials in tap water that makes it bubble up when it boils.
They boiled tap water and it bubbled the water up in the microwave.
Then they boiled distilled water and it did nothing untill they added a sugar cube and it boiled over.

This means that distilled water won't make bubbles in the rad when it gets to the boiling point.
Another reason to use distilled water.

Well, not quite... you can easily superheat pure water (distilled) using a microwave, and if you put anything into it, it will initiate boiling (e.g., sugar, coffee, dust, sand, etc.). I don't have any evidence, but I would argue that unless your tap water has chunks of stuff in it, the boiling point is hardly affected by the dissolved mineral content--maybe just a degree or two. The effect of the boiling point by the glycol is much more significant than the addition of a few minerals.

That being said, there is still good reason to use distilled. But I don't think it's because of boiling point.

 

[cruiserdan]

Distilling is good it makes................Oh, never mind

 

[archie]

Here's a link about using fluids in the radiator https://forum.ih8mud.com/showthread.php?t=18536&highlight=sterile+water

 

[LandCruiserPhil]

This interested me so I asked the science teacher (wife) and this is what she gave me.

For water to boil, two things must occur. First, the water must reach or exceed its boiling temperature--the temperature at which a bubble of pure steam inside the water becomes sturdy enough to avoid being crushed by atmospheric pressure. Second, bubbles of pure steam must begin to nucleate inside the water. It's the latter requirement that's not being met in the water you're heating with the microwave. Steam bubbles rarely form of their own accord unless the water is far above its boiling temperature. That's because a pure nucleation event requires several water molecules to break free of their neighbors simultaneously to form a tiny steam bubble and that's very unlikely at water's boiling temperature. Instead, most steam bubbles form either at hot spots, or at impurities or imperfections--scratches in a metal pot, the edge of a sugar crystal, a piece of floating debris. When you heat clean water in a glass container using a microwave oven, there are no hot spots and almost no impurities or imperfections that would assist boiling. As a result, the water has trouble boiling. But as soon as you add any impurities to the superheated water, you trigger the formation of steam bubbles and the liquid boils madly.

Reverse Osmosis water is also pure H2O good for your radiator.

Phil