[Healeys] Coolant

[Oudesluys]

Any suggested corrosive properties of distilled water (which it does not 
have, pH being around 7) are being dealt with, by the anti-corrosion and 
other dopes in the coolant or anti-freeze. The minerals in tap water 
however will not disappear, may be they are neutralised by 
anti-freeze/coolant, but why take the chance. I always use ready mixed 
coolant which is supposed to be made with distilled/demineralised water. 
In all the cars I have owned over the years the only cars having 
sediment in the engine/radiator were cars that were imported either from 
the UK or USA, countries where the use of water only as a coolant is/was 
common. All others were absolutely clean, even after 20 or more years, 
indicating that replacing the coolant is fairly common practice over here.

Kees Oudesluijs
NL


Bob Spidell schreef op 16-5-2014 6:06:
> OK, the List has been pretty quiet lately--the ongoing mail server 
> problems notwithstanding--so I'm going to resurrect an old 
> controversy: what kind of water to mix with antifreeze (i.e. some form 
> or glycol or alcohol).
>
> I've had online, er, 'discussions' with people who maintain, 
> adamantly, that distilled water is 'ion hungry' and will in no time 
> reduce an iron engine block to a mound of iron oxide, aka 'rust' 
> (according to Wikipedia, there are at least 16 different chemical 
> forms of iron oxide).  I've only got a couple years of college 
> chemistry, but I remember that distilled water is chemically 
> inert--with a perfect balance of H+ and OH- ions and pH of slightly 
> less than 7.0  due to its tendency to dissolve atmospheric CO2 and 
> form mild carbonic acid--but would, however, dissolve more mineral 
> salts due to it not having any minerals already dissolved (if you 
> accidentally dumped a pound or two of Morton's finest in your block 
> distilled water would dissolve more of it than tap water).
>
> Anyway, I had to drain the coolant in my BJ8 in order to change the 
> water pump (thanks Michael!), and the mixture--which I estimate at 
> 40/60 antifreeze/distilled H2O--was absolutely clear with no sediment, 
> and I could not see or detect any sediment in the block. The visible 
> portions of the block and cylinders developed a thin film of rust due 
> to exposure to air after they dried.   This coolant has been in the 
> engine for at least 3 years/15K miles, and possibly 4 or 5 years (I 
> really should track this stuff).  Maybe the distilled H2O is slowly 
> dissolving my engine, but it's doing so with no visible evidence.
>
> In my mind, this settles the argument but, as usual, YMMV (also, all 
> the 'pros' I've heard lately have recommended distilled H2O). Also, 
> I've heard some negative things about Water Wetter but I've been 
> adding it to the coolant for quite a while with no apparent adverse 
> effects.
>
> Bob