Increased revs - increased coolant circulation - cooler. Steady increased revs -
temp increase - hotter. Seems normal to me.
83.5 Westy

KENWILFY@AOL.COM wrote:

> Had a weird thing happen while checking out a customer's van today.  Ran the
> van up to temperature and let it idle.  It went slowly up to around 3/4 of
> the gauge before the fan came on.  I put in a new switch that now comes on
> right after the needle passes the LED (better).  However the van did
> something weird when I was trying to warm it up after replacing the switch.
> The needle was at the middle (LED) and I wanted it to heat up faster so I
> revved the motor up to around 2500 rpms and held it there.  As I watched the
> needle it actually went down in temp 1/8 of the gauge and then started back
> up again!  I had never seen this before (usually they hold steady and slowly
> climb).  Any ideas on this one?  Just normal operation and I never noticed it
> before (possible)?
> The old fan switch might have been good but the part of it that sticks into
> the rad was covered with goop (Bar's Leak?) and this could have had an
> insulating effect on the sender.
> I was wondering if the inside of the radiator is coated with goop if this
> could be messing up its heat transfer properties?  Any ideas?
>
> Thanks,
> Ken Wilford
> http://www.vanagain.com
> John 3:16
> Phone: (856)-765-1583
> Shop:   (856)-327-0027
> Fax:     (856)-327-2242