rocket:

dexcool is eg based; no difference in terms of thermal properties or
specific gravity. one cup either way is of no concern.

long-life property of OAT is lost, however, if too much, i would guess 5 -
10%, of antifreeze used in mix is conventional.

dan

On Tue, 23 Oct 2007 17:06:33 -0700, Michael Elliott
<camping.elliott@GMAIL.COM> wrote:

>So yesterday I was trying to get my coolant system in operating condition
>in preparation for a possible mandatory evacuation order (San Diego county
>fires). I borrowed a working expansion tank pressure cap to replace my
>failed one and was bleeding and re-topping up the system. Time to add some
>more coolant and I saw that the stuff was orange. No more than 250ml went
>in before I paused and thought, "Wait. This seems odd." I did a quick
>Internet search and discovered that Dex-cool (Organic Acid Technology)
>type coolants are not compatible with the ethyl glycol-based coolant I
>have in my van.
>
>At this time I have bigger concerns than a cup of orange coolant in the
>system. But for tomorrow: have I opened the door for some future problem?
>
>--
>Mike "Rocket J Squirrel" Elliott
>71 Type 2: the Wonderbus
>84 Westfalia: Mellow Yellow ("The Electrical Banana")
>74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
>KG6RCR