I recently posted about a change to Havoline Dex-cool. Since then, I've run
into this article:
http://www.consumeraffairs.com/news04/2006/08/gm_dexcool.html
SO... I'll be going back to the green after a complete flush. I had read
quite a bit about silicates and phosphates eating the aluminum cooling
system of the older BMWs and it appeared this was a solution. Apparrently it
may not be the best solution. When I replaced my water pump in April 2005, I
noticed some corrosion under the hoses at the thermostat housing. The
aluminum was being eaten! Since I had recently bought the car, I was doing
maintenance as things happened instead of all at once. Pelican discusses the
topic here:
http://www.pelicanparts.com/bmw/techarticles/E36-Coolant_Flush/E36-Coolant-F
lush.htm
Not being an engineer (kudos to those that are!), all the information I
found wasn't specific... just saying "use this coolant." A "WHY" would have
been good. So, older and newer BMWs have slightly different cooling systems,
between the aluminum and plastic parts. My '86 535i has an aluminum vice
aluminum/plastic radiator. It's practically new looking despite its age and
the aforementioned thermostat housing.
I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
the green in a 60/40-ish mix with distilled water like I used for the last
15 years in my other BMWs. It gets changed every 2-3 years with 3-4 month
checks on the system anyway. All this was necessary because I never saw
anything DEFINITIVE on the issue. Learn from my mistake (no damage!).
Fred - no harm, no foul. Here is my correction.
Bill
'86 535i
Fred W - 29 Sep 2006 15:27 GMT
> I recently posted about a change to Havoline Dex-cool. Since then, I've run
> into this article:
[quoted text clipped - 25 lines]
>
> Fred - no harm, no foul. Here is my correction.
Good deal Bill. But why would you now select the green stuff?
Do a little more research on the topic (my bad experiences with green
stuff is limited to SAABs, not Bimmers) and I think you will find that
your best bet would be to try and stick with the manufacturers specified
G-48. I know it's inconvenient to find (I buy mine from a SAAB parts
place online for $12 w/ free shipping), but the next best stuff is the
G-05 which you can buy at AutoZone in the Zerex G-05.

Signature
-Fred W
Richard Sexton - 29 Sep 2006 16:01 GMT
>I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
>the green in a 60/40-ish mix with distilled
In Mercedes circles green = evil and is enough to make most people say "pass"
when finding this in a potential car purchase. You use the golden MB coolant, period.
MB says NOT to use distilled water. This makes no sense to me; I email MB Canada and
they didn't understand it either and said it was fine. MB Germany recommends "tap
water" which is a bit idiotic. In parts of SF and some suburbs of Toronto the
water is so soft it may as well be distilled. Where I live the well water is
basically liquid rock. It's not like all "tap water" is created equal.
MB Coolant is $12/gal from the dealer and isn't like anything else. It's buffered
more strongly than anything else to prevent corrosion of aluminum and is plastic safe,
MB rads have had plastic necks since 79.

Signature
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
1970 280SE, 72 280SE | Home pages: http://rs79.vrx.net
633CSi 250SE/C 300SD | http://aquaria.net http://killi.net
Rex B - 29 Sep 2006 16:26 GMT
>> I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
>> the green in a 60/40-ish mix with distilled
[quoted text clipped - 11 lines]
> more strongly than anything else to prevent corrosion of aluminum and is plastic safe,
> MB rads have had plastic necks since 79.
A small amount of trace minerals is desirable in cooling systems. Just
the amount left when you backflush the system is enough though, refill
with 50/50 distilled water and [antifreeze of choice]
Fred W - 29 Sep 2006 19:49 GMT
>>I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
>>the green in a 60/40-ish mix with distilled
[quoted text clipped - 9 lines]
>
> MB Coolant is $12/gal from the dealer and isn't like anything else.
Actually, I believe the MB coolant is Glysantin G-05, which you can buy
a lot of places.
> It's buffered
> more strongly than anything else to prevent corrosion of aluminum and is plastic safe,
> MB rads have had plastic necks since 79.

Signature
-Fred W
Richard Sexton - 01 Oct 2006 08:52 GMT
>>>I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
>>>the green in a 60/40-ish mix with distilled
[quoted text clipped - 12 lines]
>Actually, I believe the MB coolant is Glysantin G-05, which you can buy
>a lot of places.
You sure? I'd love to have an authoritative reference for this.

Signature
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
1970 280SE, 72 280SE | Home pages: http://rs79.vrx.net
633CSi 250SE/C 300SD | http://aquaria.net http://killi.net
Fred W - 02 Oct 2006 01:44 GMT
>>>>I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
>>>>the green in a 60/40-ish mix with distilled
[quoted text clipped - 14 lines]
>
> You sure? I'd love to have an authoritative reference for this.
No. Unfortunately, I'm not positive. Maybe someone on the MB list
would know for sure.

Signature
-Fred W
bfd - 02 Oct 2006 03:04 GMT
> >>Actually, I believe the MB coolant is Glysantin G-05, which you can buy
> >>a lot of places.
[quoted text clipped - 5 lines]
>
> --
In Canada and the US, both BMW and Mercedes coolant are made by Valvoline.
BMW, and SAAB, uses Valvoline Zerex G-48; Mercedes uses Valvoline Zerex
G-05:
https://www.valvoline-technology.com/data/VALV/ValvExtSecurity.nsf/fsZerex?O
penFrameSet
I use SAAB "Blue" in my BMW!
Fred W - 29 Sep 2006 20:59 GMT
> I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
> the green in a 60/40-ish mix with distilled water like I used for the last
> 15 years in my other BMWs. It gets changed every 2-3 years with 3-4 month
> checks on the system anyway. All this was necessary because I never saw
> anything DEFINITIVE on the issue. Learn from my mistake (no damage!).
Bill, one other thing. You said 60/40 do you mean 60% water or 60%
antifreeze? The reason I ask is, even though 60% antifreeze can be run
it isn't recomended unless you expect to encounter major low temps (like
in Alaska or something) as the cooling capaboility of the mizture will
not be as efficient.
50/50 is good enough for most people and if you live down south where
cold is 30-40 degrees, 60% water is OK.

Signature
-Fred W
Bill - 29 Sep 2006 23:57 GMT
Bill wrote:
> I don't recommend the Dex-cool, despite the "no this, no that". I'm doing
> the green in a 60/40-ish mix with distilled water like I used for the last
> 15 years in my other BMWs. It gets changed every 2-3 years with 3-4 month
> checks on the system anyway. All this was necessary because I never saw
> anything DEFINITIVE on the issue. Learn from my mistake (no damage!).
Bill, one other thing. You said 60/40 do you mean 60% water or 60%
antifreeze? The reason I ask is, even though 60% antifreeze can be run
it isn't recomended unless you expect to encounter major low temps (like
in Alaska or something) as the cooling capaboility of the mizture will
not be as efficient.
50/50 is good enough for most people and if you live down south where
cold is 30-40 degrees, 60% water is OK.
--
-Fred W
-----
I have always run between 60/40 and 50/50 antifreeze/water. I don't really
know why other than possibly getting the coolant to run a little cooler
(mostly my flawed thinking? LOL). This way when I topped up, I could use
water. This helped me use all the coolant so I don't have any left over
laying around. I never buy pre-mix because they charge as much and I like
mixing my own. I was considering Water Wetter when I lived in Biloxi, MS on
the Gulf of Mexico. I was alsways hot and humid and made my car run a little
warmer than I liked. I moved to Omaha, NE this past Feb because of Katrina.
The weather in Omaha is noticeably warmer than 12 years ago when I was here
last.
Too bad we can't just run straight tap or distilled water! Hahahahah!
Bill in Omaha
'86 535i