Ten degrees less might be a little too much for the fan thermo switch.
Bus Depot sells 2 different thermostats for the vanagon.
One is 87 deg., and I think the other one is 80 deg.
I've been running the 80 deg. thermostat for more than 2 yrs.
I haven't noticed any difference in fuel consumption.
Personally I like the lower thermostat, because I believe it helps
with the longevity of the plastic and rubber parts, and head
gaskets in the cooling system.
7 deg. lower coolant temp. might make a rubber hose last
30% longer. (of course, that's just a guess).
I still use the original higher temp. fan switch, since I don't
want to wear out the fan. On freeway runs, the engine does
operate cooler. Oil temp. stays a littler lower too.
The only drawback I noticed is slightly less efficient heating
system in the winter.
In my opinion:
I don't think any automotive engineeers for the big car companies
design cars to be trouble-free for much longer than 10 yrs.
After that, we're supposed to buy a new one.
So basically we're all trying to cheat the system by driving
these cars longer. I think lowering the coolant temp. a notch
is part of that, just like ceramic coated cyl. heads, synthetic oils,
amsoil oil filters, frequent oil changes, other maintenance that
vw never suggested, like changing the power steering fluid,
rotating and cleaning cv joints, etc.
Usually it's good to stay with original specs, but some
extra maintenance and modifications might prolong the
designed lifespan, but, of course, some also might not.
Harald
'90 westy

----------
> From: The Gunnings <ngunn@LANDMARKNET.NET>
> To: vanagon@GERRY.VANAGON.COM
> Subject: Is It Cool To Be Cooler?
> Date: Sunday, June 11, 2000 9:12 AM
>
> Purchased a thermoswitch (BMW) which supposedly operates (kicks on) at a
> temperature 10 degrees cooler than the stock VW one does.  I think it is
165
> degrees as opposed to 175 degrees.  Also had to pick-up a 10 degree
cooler
> thermostat.  My question is if this is such a good idea why haven't
others
> done it and spread the word via this enlightening list?  If running Hot
is
> to be avoided, and I agree that it is, doesn't it make sense to notch the
> thermoswitch and thermostat down an easily done ten degrees?  That this
is
> not being done makes me wonder what it is that I do not know that might
make
> this not such a good idea.  Unless I receive listee contrary views on the
> subject, however, next time I drain my system, think I'll give it a try.
> Ten degrees is, after all, ten degrees.  Anyone want the part ###s, let
me
> know and I will post them on the list.
>
> Dave Gunning
>
> Lovell, ME 04051
> Kubota 4wd
> Limmer Boots