On 05/24/2012 03:42 PM, David Beierl wrote:

"Unlike the cooler thermostat which I think can be actively
harmful to the engine,[...]"

I've retitled this thread so as not to hijack the original.

The OP was asking about the fan switch on the radiator, but it brings up
an issue I am trying to sort out. I may have asked this before but I
don't think it has been settled in my mind.

Back in 2007 a vendor shipped me the lower-temp thermostat along with
the water pump I was replacing on my 1.9. I didn't notice until
everything was put back together then I saw the temp gauge running just
to the left of the LED. I contacted the vendor and he said he had done
me a favor, that it would benefit the engine.

So for about five years I've been running with that cooler thermostat.

But I read here, frequently, that it's not a good idea. (This does beg
the question why VW made the lower-temp part.)

But when I asked both of the well-regarded shops here (Steve's Place and
Old Volks Home) about swapping in the higher temp one, they both gave me
the same answer, which was along the lines of, "Why would you want to do
that? VW issued the higher temp one to comply with Cali emissions
standards, but the engine lasts longer with the lower temp one."

So, how's a girl to know?

--
Jack "Rocket j Squirrel" Elliott
Bend, Ore.