Re: S Car antifreeze

[Igor Kessel <four_rings@worldnet.att.net>]

Daniel Hussey wrote:
> 
>     So, for summertime, I should mix more water with my coolant?

Yes. Pure water would be ideal but:
1. it does not have the built-in corrosion inhibitors.
2. it does not lubricate the water pump bearing sufficiently like the
ethylene glycol does.

>  And, what
> coolant do you reccomend.  I have the pink stuff in there now, which I got from
> an imports place.  I picked up a thing of Zerex yesterday and found out it has
> phosphates in it.  Don't want to use that.  I have heard some listers using
> Sierra, but can't find it anywhere.  Anything else you'd reccomend?

Sierra is a Propylene Glycol based coolant. I have no personal
experience with it.

In my '89 200TQ I am running the racing Evans coolant. It is 100% pure
Propylene Glycol, totally water-free. It operates at zero pressure and
is very effective. The only downside is the price of the coolant
($27/gal), but the specs say it is good for 100 kmi of service. With its
zero pressure operation I am not worried of losing any due to a burst
hose or a leaky radiator.

The cooling sys was modified: the spouted Vanagon cap (pressure relieve
valve removed) and the secondary recovery sys (based around an expansion
tank off an Asian car) were installed.
Also, the car has the coldest thermostat I could find: 78°C (Porsche 944
application) which is drilled in three places to facilitate the coolant
flow.

Judging by the unsuccessful experiments with Evans on the S cars (Larry
B. '93 S4 for one) the consensus seems to be not to do the Evans
conversion on these cars. Pity, coz I have just bought an S6 and would
love to do it.

> I guess
> the Autobahn coolant from the dealer would be best, but just wondering if there
> is something out there that would increase cooling capacity.  What about that
> Redline Water Wetter stuff?

I tried this product but it failed to decrease the operating t-re. What
it did however was create the brown oil-like droplets suspended in the
coolant as if the head gasket were blown. These observations coincide
with that of a few other listers. In a word - I was disappointed.

-- 
Igor Kessel
Three turbo quattros