Coolant to water ratio?????

[37PackardMan]

I see all the antifreeze/ coolant MINIMUM ratios listed as 50-50 which protects down to -34F.

So if you live in warm climates like San Diego, Houston, MIami, why do you have to protect down to -32F?

Isn't it adequate to use 25% solution to 75% water?  What is the real drawback? corrosion protection? lubrication? ...or is it a ploy to sell more product?

[padgett]

I suspect it is the 265F boiling point they are concerned about.

[Frank DuVal]

In non-automotive cooling applications, we use ethylene - glycol solution in whatever ratio with water that is required to keep it from freezing. 10%, 15%, etc. The more ethylene - glycol we used, the less the heat transfer was, and we were more interested in getting maximum heat transfer from our processes to the air. We check the percentage with a refractometer to be sure.

 

Anti-Freeze has more stuff in it than pure instrument grade ethylene - glycol, but probably not more than a percent or two. I would say it is CYA by the anti-freeze maker to prevent engine block damage from solid water breaking stuff. "I know the product was defective and they owe me a new engine because I added 25% antifreeze for my area" not knowing the correct capacity of the system and only adding 15%......  Or suddenly the temperature drop 20°F below normal for two days......

 

Use a refractometer ( of course, no one has those at home...)  or the simple ball hydrometer to check freeze point of solution to be sure. Drive happy.😉

 

Yes, boiling point is more of an issue in warm climates. 

Edited December 3, 2018 by Frank DuVal
Padgett's comment (see edit history)

[joe_padavano]

With a 16 psi cooling system, even straight water doesn't boil until nearly 265 F. Note the footnote that points out the temps assume a 15 psi system. Antifreeze does nothing for boiling point.

Edited December 3, 2018 by joe_padavano (see edit history)

[Joe in Canada]

Seeing that jug is yellow and if it is Prestone do not use it if your radiator is copper.

[28 Chrysler]

4 hours ago, Joe in Canada said:

Seeing that jug is yellow and if it is Prestone do not use it if your radiator is copper.

It is often stated "will work on older vehicles". What they mean is around 10 years old.

[Pfeil]

Remember when you buy coolant do NOT buy premixed. Buy coolant that is concentrated and when you mix it with water make sure it's DISTILLED water.

The 50/50 mix uses tap water.

[joe_padavano]

6 hours ago, Joe in Canada said:

Seeing that jug is yellow and if it is Prestone do not use it if your radiator is copper.

 

Huh?  I've been using green Prestone from a yellow jug in all my vehicles for the last 45 years.  That includes cars dating back to my 1962 Olds.

[Spinneyhill]

6 hours ago, Joe in Canada said:

Seeing that jug is yellow and if it is Prestone do not use it if your radiator is copper.

Eh? All antifreezes are forumulated to NOT attack ANY metal or alloy or amalgum. They contain anti-corrosion additives. Remember that modern engines contain metals that are right at the top of the galvanic series - aluminium and magnesium -- and are much harder to protect from corrosion than older cast iron engine, copper and solder radiator, brass or bronze bits in the water pump, temperature sender and so on.

 

I have commented on this before.

 

2 hours ago, Pfeil said:

Buy coolant that is concentrated and when you mix it with water make sure it's DISTILLED water.

Distilled water is a good idea to prevent scale in the system. But scale will only build up on a surface when water evaporates, so in the top of the radiator. Distilled water is not necessarily de-aired or de-oxygenated and if it were, air is mixed into it by turbulence in the top of the radiator.

[Bloo]

With all the sky is falling warnings all over the Internet I would probably believe this except.... some salesman talked me into trying "phosphate free" antifreeze back in the 1980s, before it was a common thing. I liked it because it makes a much smaller mess if it leaks or boils, and have been using it in most of my cars since..

 

I am in my 50s now and am wondering how long it is going to take for this stuff to eat a radiator. Will I live long enough to see it? I'll keep watching. Here is a car with over 200k on it. It is a 1991 and has had nothing but DexCool and distilled water since the summer of 1996 (and 60k miles). The radiator core and the heater core are brass/copper and both are original. When they fail, if I live long enough to see it, should I blame the antifreeze?

 

There are more examples in my "fleet". Change your coolant regularly and everything will be OK.

 

 

[Frank DuVal]

I’m with Joe, been using yellow Prestone jugs since I started driving in the late 60s. No issues. Well, my not changing it often is my issue, not Prestone’s!