Flushing, then topping up the Radiator

[fenderbender]

After removing the old water / coolant in the radiator, some say that topping-up the radiator with 100% distilled water is better. Some claim, distilled water will not rust the radiator and other parts unlike ordinary tap water.

Some say, that coolant is not really needed. Some say its a must.


What are your thoughts?

[afrasay]

coolant (prestone, etc) raises the boiling point of water in your radiator. Yes, distilled water is a wise choice. It has less or no mineral deposit that could corrode your radiator.

[knights]

Well this is what I know about radiators and how to maintain it:

Radiators are used as a heat exchanger to get the heat from the engine and then will give it out to the ambient (colder) air to transfer the heat again. This will in turn make the water cooler and ready for another heat exchange.

Distilled water are good in radiators because they will not cause scaling. Scales (ito iyung nakikita mo pagnagpakulo ka ng tubig na galing sa gripo then naiiwan sa kettle na parang maputi na pulbos) are formed because of impurities in the tap water. Tap water has so many minerals while Distilled water are more purer because minerals are stripped off from its process. If you have thick scales it will reduce the heat exchange capability of your radiators because it will act as insulators, thus it can cause over heating of engine if not cleaned or properly maintained.

The disadvantage of distilled water is that its pH is normally less than 7.0 (naalala natin sa Chemistry 101 na pag 7.0 ang pH ito ay neutral pagka less than 7.0 ito ay acidic and if more than 7.0 it is basic). So if the pH of the distilled water is less than 7.0 it is acidic and will attack the metals of the radiators fast.

Though, If you use tap water which the pH range is still 7.0 to 7.2 it will still corrode the metal, though the corrosion will be much longer to realized than using a distilled water. By the way, There is no such thing as eliminating corrosion we can only minimize it or make the metals be of use to us longer. because corrosion is a natural process that takes place what we just take out from nature.

This where coolant comes in and helps maintain our radiators. coolants are glycols, glycols increases the boiling point of water from 100 deg. to 125 deg. C and reduce the freezing point of water from 0 deg. to -25 deg. C. (ito po iyung naalala ko paki-correct kung may mas nakakaalam ng more accurate figures- thanks). Kaya ang tawag po din sa coolant lalo na sa ibang bansa ay anti-freeze.
Anyway, so if we increase the boiling point of water to 125 deg. C mas matagal syang kukulo and we will have a higher threshold level.

Now coolants or glycols also acts as anti-rust because of its properties. The next info is important to know, we need to change our coolants/or glycols (meaning, we need to flush and replace it with new) normally once every 12 months to be sure. The reason is that Glycols breakdown after sometime, and when it breaksdown it forms Glycolic acid, this acid will accelerate the corrosion. Ito na po iyung may nakakapagsabi sa atin na kapag may coolant eh mas lalo nang nagpapakalawang. kailangan lang pong palitan periodically to minimize corrosion.

Again this is important.. Coolants will not work alone, this must be a mixture of water and coolants, normally 30% coolants and 70% water. Pwede din 50% each for the mixture. Pwede nyo ding tingnan sa instruction of each coolant sa market for proper application.

My 2cents...Hopefully this information helps...

[afrasay]

well said, knights

[jim]

I never used coolant. I never experieced overheating without coolant maybe its because I have a 5 column radiator. But what I do always to keep my radiator in top shape is to flush it frequently and have it checked for leaks and cleaned regularly so that all tubes inside the radiator are free from mineral deposits that clog them.

[woodfire]

in my experience, this is what I do to the radiators of my vehicles:

1) put in a flush/radiator cleaner ( i use prestone flush cleaner) and run the engine 2-3 hours.

2) i drain and flush the water & scales

3) then, i mix in a pail of "filtered water" (not distilled water). my house has a 5-stage water filter so this is what I use. I mix in a lubricant/coolant called "OBERON" with a ratio of 10 liters of water to 50ml of Oberon. after mixing it in a pail, I put it in the radiator. Oberon is quite pricey though but highly recommended by MBenz and BMW dealers in the U.S.

[theveed]

In addition, coolants function as a lubricant for your waterpump as well. Without it, your waterpump will wear off faster, especially the bearings.