[2fast4u]

ive been driving this nissan altima(my photo gallery) (popularly known as cefiro in SE Asia) earlier Dubai now in Bahrain. Earlier i used to top it up with normal tap water. i had never done radiator flush until reading this on TBHP - thanks.

I did a flush of the the cooling system recently using some kind of flakes for the flushing process done at a professional garage, was a 2 hour process drain to top up. There was a lot of rust, debris that came out during the flushing. the attendant mentioned not to use tap water but direct coolant premix with distilled water (5 ltr can for top up) if there was no distilled water readily available mineral water ''''can''' be used but not recommended.

the flusing is done 4 months now and during this period I have topped the coolant reservoir and the radiator with approx 3 ltrs of coolant.

THERE were and as of now NO LEAKS. Having read some sites that coolant cannot evaporate would like to know if this is true, as i was thinking that with apparent temperatures around 50C with AC on the coolant should evaporate to some extent.

let me know if this is right.

[dadu]

Coolant does evaporate but in very small quantities over longer period of time as compared to water.

Usually the radiator is filled with a water/coolant mix and the reservoir is filled with pure coolant and it is also right to suggest not using tap water since it might contain some impurities like hardness.

[vikram_d]

Any liquid above its boiling temperature will evaporate. In the case of coolant, the coolant itself does not evaporate but the water does. The coolant used these days has a higher boiling point than water. Therefore topping up with only water is recommended.

[Hellcat]

@2fast4u : This is what I know, the radiator coolant must have a good mixture of water and coolant so that your car has adequate freezing and boiling protection. Finally, some corrosion inhibitors might be helpful as it can protect against rust and electrolysis. Most cars lose some radiator coolant due to evaporation. This happens by the heat produced by the car’s engine, and also do check your radiator cap if the cap is not tight enough coolant evaporation is possible and it wont keep the air out of the cooling system.

cheers
Hellcat

[Gurkha]

MB recommends against distilled water due to its corrosive action on metals, instead use RO water. 50:50 mix is the best for performance and boil over protection, remember, more coolant means less heat transfer.

[lohithrao]

@Gurkha: what is RO water??

[Hellcat]

The mixture of Coolant should be 65% to 70% with water, because too much coolant and not enough water will actually reduce the coolant’s ability to carry and process heat.

RO (Reverse osmosis) water is nothing but purified water which is clean from substances commonly found in tap and well water. (Aquaguard, ZeroB Etc)

[lohithrao]

@Hellcat: Thanks for the info

[Gurkha]

Originally Posted by Hellcat

The mixture of Coolant should be 65% to 70% with water, because too much coolant and not enough water will actually reduce the coolant’s ability to carry and process heat.

RO (Reverse osmosis) water is nothing but purified water which is clean from substances commonly found in tap and well water. (Aquaguard, ZeroB Etc)

RO is different from aquaguard, Zero B etc. those are just ordinary filtered water with UV treatment for bacteria and charcoal filtering for sediments, RO OTOH is all that plus water passed through reverse osmosis process through a membrane, this water has the lowest amount of TDS ( total dissolved solids ) which is way less than water passed through regular filtration. Its safe for your cooling system, mix 50% water with 50% coolant which is the OEM recommended mixture ratio and flush your radiator system with a radiator flush from time to time, every 3 years at least and you will have a cool and happy running engine. Remember, neglecting coolant change will lead to deposit build up and ultimately costly radiator repair as well as equally costly engine block flush.

[Hellcat]

@Gurkha: aquaguard, Zero B also have reverse osmosis base purifiear.

[Gurkha]

Originally Posted by Hellcat

@Gurkha: aquaguard, Zero B also have reverse osmosis base purifiear.

Hellcat, none of them are reverse osmosis and neither do they have RO membrane, I know that Eureka Forbes makes a RO unit by the name of Spring Fresh.

[Jaggu]

better to use distilled water in order to avoid all the salts and stuff. evaporation yes will happen to an extent, as in a minor top up every 5000 kms is ok (usually done in the reservoir tank)

[vivekiny2k]

i use readymade 50:50 mixture from the store.

2fast4u, check ur system for leakage. first thing I would suggest is the radiator cap. it comes cheap(er) than rest of the components.

a failed cap will cause your coolant to evaporate via the cap opening. hence no leakge noticed on floor etc. Think of it as a failed gasket in a pressure cooker. the water just evaporates.

[dadu]

Originally Posted by Gurkha

Hellcat, none of them are reverse osmosis and neither do they have RO membrane, I know that Eureka Forbes makes a RO unit by the name of Spring Fresh.

OT: Gurkha is right about the RO, some known products for RO are like KENT RO system.

[low_bass_makker]

RO is just like a very fine filter in which water is passed through it at a little pressure and all the salts in the water are trapped inside the filter thats why when the RO is cleaning the water only 20-30 % yield and the rest is wasted.....the RO water is having a 20-30 PPM impurities and it is a good substitute of distilled water but not distilled water...