Thanks Dave.  I wouldn't be worried except that my needle typically hovers
around the 3/4 mark and is at 7/8s of the dial going up that hill.  And
I've seen the red light come on a couple of times -- both times I've pulled
over asap and it has not come back on after letting it cool a bit.  So I
keep thinking there's a problem with the high speed fan.

But maybe it's a wonky gauge.  I'll put the infrared gun in the van and the
next time I see the red light come on, I'll take the temp at the rad.

Rick

On Tue, Sep 5, 2017 at 8:06 PM, ddbjorkman@verizon.net <
ddbjorkman@verizon.net> wrote:

> The Vanagon coolant system, when working correctly, is actually quite
> robust.  There is an A/C condenser in front of the radiator that VW took
> into consideration.  As long as you are moving, not stuck in traffic, even
> at 85+F ambient temp, the low speed fan takes care of things.  As long as
> your temp guage doesn't get beyond 3/4 and no flashing red light happens,
> it's working correctly and don't worry about it. To more fully answer your
> question, your coolant has to reach 85 C/185 F to just turn on the fan.  It
> takes 95 C/203 F to get the fan to get to high.  That's a lot of degrees.
> It's amazing how much one can learn when one has to research a problem.
> What's that about VW making owners into mechanics for the past 30 years.
>
> Dave B.
>
> -----Original Message-----
> From: Rick Cooper <rickdcooper@GMAIL.COM>
> To: vanagon <vanagon@GERRY.VANAGON.COM>
> Sent: Tue, Sep 5, 2017 10:14 pm
> Subject: Re: Radiator fan switch
>
> I've got the same or at least a similar problem with my radiator fan.
>
> The low-speed fan kicks in as expected but the high-speed fan never kicks
> in. But I know it works since I've done the jumper test at both the switch
> and at the high-speed relay. I have replaced the switch.
>
> Maybe the coolant is not getting hot enough for it to kick in -- I'm in
> Victoria, BC where it never really gets super hot, but I would have thought
> that going up long hills at highway speed on a hot day (~85 degrees F)
> should be enough to trigger the high-speed fan.
>
> At what temp should it kick in? I've got an infrared temp gun so I could
> test that.
>
> Thanks, Rick
>
> On Tue, Sep 5, 2017 at 3:24 PM, Dennis Haynes <d23haynes57@hotmail.com>
> wrote:
>
> > Is the radiator getting hot? For testing the wiring there are three wires
> > on the fan switch. One is power from the fuse box. That wire jumped to
> the
> > middle will give you slow speed. The two outside wires jumped will give
> you
> > super-fast high speed. If the fan turns on with the AC than most likely
> the
> > fan resistor is good. It is possible you just are not getting the coolant
> > hot enough to call for the fan. Infrared temp gun can help here.
> >
> > Dennis
> >
> >
> > -----Original Message-----
> > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com
> <vanagon@gerry.vanagon.com?>] On Behalf
> > Of David Bjorkman
> > Sent: Tuesday, September 5, 2017 1:24 PM
> > To: vanagon@GERRY.VANAGON.COM
> > Subject: Radiator fan switch
> >
> > Hi all;
> > Still in SC. replaced the radiator and condenser (after some body work)
> > and am having trouble with the fan coming on. Turning on the A/C gets
> > starts the fan, so I know it works, but it won't start when the engine
> gets
> > hot. Fuses check out OK. How does one check the radiator fan switch. I
> > know that I have to jumper something, but not sure what. I would really
> > like to get this fixed and get back home.
> >
> > Thanks;
> > Dave B.
> >
>