Honda Car Forum

On 23 Aug 2003 19:28:19 -0700, jcdech@hotmail.com (John D.) wrote:

>So the saga continues: What antifreeze to use that WILL protect your
>cooling system from corrosion but will NOT cause water pump problems.

Here's the short story:

Japanese manufacturers typically recommend no silicate antifreeze.
Apparently, as the story goes, the silicate can wear the seals and
cause leaks in the WP. Maybe they just make lousy seals, I dunno.

Prestone green is *high* silicate. It is the *opposite* of what you
should put in a Japanese car. Prestone introduced their high
silicate blend in the 70's as a cure for corrosion problems. More
silicates, less corrosion. I would not use Prestone in Jap car.

Valvoline sells a coolant called G05. It is _low_ silicate (not
silicate free) and has other corrosion protection chemicals.
It has been in use in Europe by Mercedes, Saab, and others for
many years and has proven out well. Ford and Chrysler have
recently adopted it as their new coolant.

GM has been using Dexcool by Havoline (Texaco). There have been
some serious issues with Dexcool. It's apparently fine in a
perfectly clean system and goes the 5 years. However, it there
is _any_ contamination, you get corrosion in new cars - some only
2 years old. Contamination includes leftovers from GM's "stop
leak" that is run through at the factory (in new cars, imagine
that) and from air (yes, normal air) in the system. There are lots
of claims and suits against GM. Some folks claim that the Dexcool
product it self is contaminated out of the barrel. FWIW, GM is
rumored to be changing to another manufacturer this year.
It is also silicate *free* but has issues. Do a web search if you
like.


So, what to use ? Use Jap coolant to be safest. Use G05 with a
simple water flush to play it a little riskier with a low silicate
product. Use a Dexcool product with a serious flush if you want to
go higher on the risk scale with a no silicate. (Personally, if I
was bent on _no_ silicates, I'd just buy Nissan coolant and avoid
the risk of Dexcool like coolants)

Bob

It's not quite as simple as that. The origins of the variations between the
Japanese and European cars can be traced to water quality. In Europe the
water is predominantly hard. As a result of this, they typically have a
formualtion from the factory that can accomodate some "hard" water without
degrading the corrosion inhibitors too much. The Japanese formulation does
not accomodate hard water and distilled water is recommended.
The problem with Dexcool is not a "clean" system issue, it is a
precontamination with silicate issue. Dexcool works by allowing an initial
corrosion that subsequently protects.Dexcool takes quite a bit of driving to
become effective - approx 1,000 miles. Silicate works by deposition over
the metal and plating - This process is a much more aggressive one, and is
instant. When you convert and try to flush out silicates, you will not get
all of it out. If the silicates are still active and plated on the metal ,
you get silicates actually neutralizing the Dexcool. Thus you get no Dexcool
protection and then the silicates are worn out. This leads to no corrosion
protection - on one flush and refill.

If you convert to Dexcool, do flush, install Dexcool. Drive 1,000 miles,
Flush again and install Dexcool. You will find that many people who have
problems with Dexcool after a conversion did not flush a second time and
reinstalled. A single flush will not do it. Also once some silicates get in
there, you ideally need to flush twice again.

The problem with silicates is that they rapidly deplete and must be flushed
out periodically or they gel and cause problems. Honda coolant is supposed
to have "organic" protection which I suspect is Dexcool related. The big
difference is that they don't claim long life and Dexcool should also be
treated similarly.

Many of Dexcool problems start from post conversion contamination by people
just adding "antifreeze". Consumers and gas attendants need to be told that
the two types of antifreeze cannot be mixed. Colors are also meaningless.
"'nuther Bob" <norealaddy@somephonydomain.com> wrote in message
news:fdchkv0l4vv35sa2em975tik09dpdl8kju@4ax.com...
> On 23 Aug 2003 19:28:19 -0700, jcdech@hotmail.com (John D.) wrote:
>
> >So the saga continues: What antifreeze to use that WILL protect your
> >cooling system from corrosion but will NOT cause water pump problems.
>
> Here's the short story:
>
> Japanese manufacturers typically recommend no silicate antifreeze.
> Apparently, as the story goes, the silicate can wear the seals and
> cause leaks in the WP. Maybe they just make lousy seals, I dunno.
>
> Prestone green is *high* silicate. It is the *opposite* of what you
> should put in a Japanese car. Prestone introduced their high
> silicate blend in the 70's as a cure for corrosion problems. More
> silicates, less corrosion. I would not use Prestone in Jap car.
>
> Valvoline sells a coolant called G05. It is _low_ silicate (not
> silicate free) and has other corrosion protection chemicals.
> It has been in use in Europe by Mercedes, Saab, and others for
> many years and has proven out well. Ford and Chrysler have
> recently adopted it as their new coolant.
>
> GM has been using Dexcool by Havoline (Texaco). There have been
> some serious issues with Dexcool. It's apparently fine in a
> perfectly clean system and goes the 5 years. However, it there
> is _any_ contamination, you get corrosion in new cars - some only
> 2 years old. Contamination includes leftovers from GM's "stop
> leak" that is run through at the factory (in new cars, imagine
> that) and from air (yes, normal air) in the system. There are lots
> of claims and suits against GM. Some folks claim that the Dexcool
> product it self is contaminated out of the barrel. FWIW, GM is
> rumored to be changing to another manufacturer this year.
> It is also silicate *free* but has issues. Do a web search if you
> like.
>
>
> So, what to use ? Use Jap coolant to be safest. Use G05 with a
> simple water flush to play it a little riskier with a low silicate
> product. Use a Dexcool product with a serious flush if you want to
> go higher on the risk scale with a no silicate. (Personally, if I
> was bent on _no_ silicates, I'd just buy Nissan coolant and avoid
> the risk of Dexcool like coolants)
>
> Bob
>
>
>
>
>
>
>
>
>

On Sun, 24 Aug 2003 15:28:56 -0400, "Mikey" <%noospaam)mikling@eol.ca>
wrote:


>Many of Dexcool problems start from post conversion contamination by people
>just adding "antifreeze". Consumers and gas attendants need to be told that
>the two types of antifreeze cannot be mixed. Colors are also meaningless.

Agreed, but that doesn't account for cooling system corrosion
in 2 year old GM vehicles that have never had any coolant added.
These are suffering from either impurities in the cooling system
right out of the factory (GM admits to some of this), contaminated
coolant right out of the barrel (GM admits to some of this by
planning to change to a new carbo formulation from someone other
than Texaco this year), and from consumer introduced contamination
including plain old "air".

Bob