Engine coolant water options...

Engine coolant water options...

Author
Discussion

Lannister902

Original Poster:

1,540 posts

104 months

Tuesday 5th March
quotequote all
Hi,
My bmw (n55) needs engine coolant, there seems to be differing opinion on the matter, so I'll ask on here!

Will dionised water work as well as distilled water? Or can I just use tap water will the coolant?

Thanks

Edited by Lannister902 on Tuesday 5th March 15:39

Haltamer

2,457 posts

81 months

Tuesday 5th March
quotequote all
Deionized is my favourite - Usually sold for battery topups or use in Irons, so you can get it in Tesco easily wink

Distilled is also good.

Avoid tap water or bottled water unless emergency; Mineral content in the engine is best avoided.

alangla

4,843 posts

182 months

Tuesday 5th March
quotequote all
Reading this thread prompted me to go and look at the coolants that OEMs are selling, is it only VAG that only sell ready-mixed rather than concentrate? Kind of annoying paying for a product that you just know is likely to be 50% water or more.

Lannister902

Original Poster:

1,540 posts

104 months

Tuesday 5th March
quotequote all
Haltamer said:
Deionized is my favourite - Usually sold for battery topups or use in Irons, so you can get it in Tesco easily wink

Distilled is also good.

Avoid tap water or bottled water unless emergency; Mineral content in the engine is best avoided.
I can't seem it find any distilled water unless buying online, deionized water seems to be available from supermarkets...

MustangGT

11,641 posts

281 months

Tuesday 5th March
quotequote all
I would not be using any sort of water, you will be diluting the antifreeze. Ask a BMW specialist what type of coolant they use and buy some of the same.

Lannister902

Original Poster:

1,540 posts

104 months

Tuesday 5th March
quotequote all
MustangGT said:
I would not be using any sort of water, you will be diluting the antifreeze. Ask a BMW specialist what type of coolant they use and buy some of the same.
It's the genuine BMW coolant, it's recommended to add water to the coolant at 50%-50% coolant to water. It's just the type of water that's in question

Pica-Pica

13,847 posts

85 months

Tuesday 5th March
quotequote all
I use de-ionised water. Available from Halfords.

Chris32345

2,086 posts

63 months

Tuesday 5th March
quotequote all
MustangGT said:
I would not be using any sort of water, you will be diluting the antifreeze. Ask a BMW specialist what type of coolant they use and buy some of the same.
Ou are away if you don't mix it with 50% water your are reducing how effective the coolant is?



The coolant on virtual all cars on the road is a 50% mix of water and coolant/antifreeze

donkmeister

8,222 posts

101 months

Wednesday 6th March
quotequote all
I've always used deionised, it's cheap and right there next to the coolant in most places that sell coolant however... Is the fear about tap water justified? Yes it contains minerals however it's in a closed loop system so can only deposit what's in the water you used when you changed the coolant - it's not like a kettle that you refill frequently. We're talking 190mg/l in England and 30mg/l in Scotland. On top of that the coolant reduces scale formation.

So I wonder how many coolant changes before that level of mineralisation becomes an issue? Not trying it with my engine, mind biggrin

Belle427

9,011 posts

234 months

Wednesday 6th March
quotequote all
Ive always used tap.

Gary C

12,494 posts

180 months

Wednesday 6th March
quotequote all
Belle427 said:
Ive always used tap.
Same here (though lancaster has very soft water)

But, as the coolant isn't boiling (hopefully) the minerals should not be coming out of solution in great amounts anyway and corrosion is inhibited by the antifreeze.

E-bmw

9,244 posts

153 months

Wednesday 6th March
quotequote all
Coolant is (generally) 50/50 water & antifreeze (with added additives) but antifreeze needs diluting to answer a few incorrect posts above.

De-ionised is fine & is basically the same as distilled but the process it goes through to become mineral free is different.

Personally, I have always used either for full coolant changes but for top ups, which is virtually nothing over a year I have no issue with using tap or cooled boiled water from the kettle.

Gary C

12,494 posts

180 months

Wednesday 6th March
quotequote all
E-bmw said:
.. using tap or cooled boiled water from the kettle.
Whats the reason for using boiled water ?

E-bmw

9,244 posts

153 months

Wednesday 6th March
quotequote all
Gary C said:
E-bmw said:
.. using tap or cooled boiled water from the kettle.
Whats the reason for using boiled water ?
Not sure how much of a difference it makes, but my theory would be as the kettle gets a coating of scale from boiling the water, this must remove some of it from the water.

ETA. I suppose thinking about it more, if nothing else it will remove/kill any bacteria etc.

Might make no difference, but that is my thought process.

Edited by E-bmw on Wednesday 6th March 11:31

tapkaJohnD

1,945 posts

205 months

Wednesday 6th March
quotequote all
The difference between de-ionised and distilled water lies mainly in the method of preparation.

Distilled is boiled water vapour, condensed by cooling. As long as it is not contaminated in the collection process it is PURE water.
Deionised is made by passing it over ion exchange resin, to remove minerals. But ion 'exchange' does not produce water that contains nothing else.

The process of deionising water is cheaper than distilling it.

John

donkmeister

8,222 posts

101 months

Wednesday 6th March
quotequote all
tapkaJohnD said:
The difference between de-ionised and distilled water lies mainly in the method of preparation.

Distilled is boiled water vapour, condensed by cooling. As long as it is not contaminated in the collection process it is PURE-ish water.
Deionised is made by passing it over ion exchange resin, to remove minerals. But ion 'exchange' does not produce water that contains nothing else.

The process of deionising water is cheaper than distilling it.

John
EFA biggrin

It's quite pure, but it's not 100% pure. 99.99% is clearly good enough for all practical uses in cars and homes, mind.

One of my Chemistry friends started to tell me about a process he uses to make ultra pure water, IIRC it involves reactions to make hydrogen and oxygen and then combustion/condense. But that's only suitable for tiny quantities and rather expensive in time and materials.

trickywoo

11,853 posts

231 months

Wednesday 6th March
quotequote all
Just to throw a cat amongst the pigeons de-ionised water will want to re-ionise and distilled water is acidic.

Just saying.

donkmeister

8,222 posts

101 months

Wednesday 6th March
quotequote all
trickywoo said:
Just to throw a cat amongst the pigeons de-ionised water will want to re-ionise and distilled water is acidic.

Just saying.
Isn't all water, distilled or otherwise, amphoteric and hence acidic?

TwinKam

2,998 posts

96 months

Wednesday 6th March
quotequote all
donkmeister said:
trickywoo said:
Just to throw a cat amongst the pigeons de-ionised water will want to re-ionise and distilled water is acidic.

Just saying.
Isn't all water, distilled or otherwise, amphoteric and hence acidic?
Not down here in God's own counties by the Sarf Coast it t'aint, you can't even see through it some days!

trickywoo

11,853 posts

231 months

Wednesday 6th March
quotequote all
donkmeister said:
Isn't all water, distilled or otherwise, amphoteric and hence acidic?
No. Distilled is more acidic than tap. It bonds with atmospheric co2 at the first opportunity.

It’s nothing the coolant package can’t cope with but I’ll always go for premix given a choice.

Edited by trickywoo on Wednesday 6th March 16:24