How do [external] oil coolers Work?

[camron at worldaccessnet.com (Camron D. Crouse)]

Rick Kellner wrote:

>Many of the components discussed can be found at the following site.
>
>
>http://www.volkswagencountry.com/empioilsys.htm
>
>Rick.
>
>
>
>The first one (liquid to liquid) uses engine coolant running in and out
>of
>the two pipes.  In steady state running, the coolant is cooler than the
>oil and therefore heat is transfered from the oil to the coolant.  This
>setup is more compact than the external setup, but requires running
>additional coolant lines if the plumbing isn't already there.  One
>advantage is the engine warmup time is reduced due to the transfer of
>heat
>between the cooling and oil systems.  One disadvantage is the cooler can
>corrode and mix the two fluids.
>
>The second system (air to liquid) uses air to cool the oil.  Oil runs
>through the sandwich adapter plate to the cooling radiator and air
>traveling through it extracts the heat.  This system is more efficient
>at
>extracting heat because there is a greater differential in the
>temperatures of the oil and air.  Because this system uses air for
>cooling, it's a good idea to have the thermostatic adapter to control
>oil
>flow to the cooler until the oil is up to temperature.
>
>I prefer the air to liquid system.
>That's it in a nutshell.
>
>-Dick-
>78 Scirocco
>Original Owner
>95 Passat
>Second Owner
>
>
>Neptuno
>  
>
>>There has been much talk on this list at different
>>time about buying and instaling external oil coolers
>>from volvos and sanwdish style oil coolers from GTI's
>>and so fort, but how do tghis things work? DO they all
>>work the same? Some seem to be coolant cooling oil and
>>others seem to be oil coolers getting cooled by a
>>radiator type cooler. Is that right? ARe there more
>>than one way to cool the oil?
>>
>>Here is that sandwish plate one
>>
>>    
>>
>http://vw-parts.drivewire.com/buynow-vw/water-cool/oil-cooler~pgn1~pcd34
>78.html
>  
>
>>Here is the external version(the one Im most confused
>>over)
>>http://www.gprparts.com/brands/gprOilCoolerKit/
>>
>>TIA
>>tony
>>
>>    
>>
I am also interested in an external oil cooler/oil thermostat kit, for 
my 2.0 16V  I am running the Evans NPG+ waterless coolant 
<http://evanscooling.com/main25.htm> and Dyson Synergyn 15w-50 Synthetic 
oil, and during bumper-to-bumper rush hour traffic my engine temps get 
quite high.  Oil temps 250+ degrees F, and coolant guage above 3/4 hot.  
My temp guages ran much cooler when I had regular antifreeze/water in 
the cooling system, but I prefer the noncorrosive nature of the Evans.

David U., I know you have spoke highly of running an external oil 
cooler... what do you recommend?  Anybody else have opinions?  Here's 
what I have been made aware of:

Autotech/Setrab kit: US$419.95 SS Braided hose / US$389.95 Poly hose 
<http://www.autotech.com/catalog/oilsys.htm>
GPR Oil Cooler kit:  US$189.00  
<http://www.gprparts.com/brands/gprOilCoolerKit/>
Volkswagen Country kit: up to US$109.76 
<http://www.volkswagencountry.com/empioilsys.htm>

Quite a stratifiaction in prices.

Thanks


- Camron from Vancouver, WA USA
   '86.5 Black 16V 2.0L