Tap or de-ionised/distilled water?

Stephen_Leak

Which is actually best in an engine? Is there any difference? I know that tap is free, but de-ionised/distilled isn't that expensive. I rely on my car and don't want to "spoil the ship for a ha'porth of tar".

closed

de-ionised is for batteries, tap is fine for the engine (antifreeze and screenwash reservoirs)

vaio

I thought “sealed for life”/”long life” antifreeze should be used with distilled water. Makes sense to use the same for topping up in the rare occasions you need to do it.

On the other hand if it’s a leaky old car then anything from ditch water up will be fine

anewman

You can get an effect similar to that on the element of a kettle (although more new water passes through a kettle) on the inside of your radiators and engine block. I am sure tap water also stains the plastic in the expansion tank, making it opaque and difficult to see the level (unless this is just due to plastic ageing and heat etc). I would guess when people's VW coolant level sensors (two prongs in the expansion tank) play up it's due to deposits building up on them from using tap water.

ioscorpio

I use cooled boiled tap water to top up my radiator.

vaio

ioscorpio wrote: »

I use cooled boiled tap water to top up my radiator.

Isn't that the worse thing you can do?

It's sort of the opposite of using distilled water so you're adding concentrated crap to your system

.

thescouselander

Money saving tip - if you do ever need de-ionised water you can get this for free if you have (or know someone that has) a condensing dryer - the water that is collected in the tank is actually de-ionised.

jaydeeuk1

Evian for mine from half finished bottles. Only the best

Would probably cause problems with mineral deposits years down the line, but as my pcp ends in 30 months, I wouldn't care.

jack_of_all

Yep putting boiled water in is more concentrated with any minerals than before it was boiled. Ive known several people who use to put boiled water in their car batteries as though it was half way to been distilled, scary thing they didn't agree with me and continued doing it. Like the idea about water from a condenser drying, my girlfriend has one, I am a bit of a collectormaniac, I'll probably collect gallons now it case i ever need it then use 1 litre a year.

cyclonebri1

The additives in antifreeze will more than overide any impurities in the radiator water. I can't see any neccessity for Peckham Spring water. It's a sealed system, well virtually. One dose of water plus anti freeze, which is as important for it's anti corrosive properties, is all thats needed, top up with the same ratio as needed, jobs a goodun. :T

In my view the use of the correct grade of anti freeze is the real issue.;)

epninety

vaio wrote: »

Isn't that the worse thing you can do?
It's sort of the opposite of using distilled water so you're adding concentrated crap to your system
.

So you boil the water, and it furs up your kettle... and somehow the impurities are higher than for the original tap water? Have you created mass from energy? Or does the kettle draw impurities out of the air around it? :rotfl:

I don't understand...