Last summer, when I was having oil pressure monitoring problems, and thought the oil pressure on my van was low, I was having cooling problems as well, and was driving at temperatures above 100 F.  I suspected that the van running hot caused the oil pressure to be lower than it should be.  One fix I thought of to get the van to run cooler was to put in an 80 C thermostat.

I didn't do that.  Think about it.  The point of the thermostat is to allow the coolant to heat to operating temperature.  Once it reaches that temperature, the thermostat is going to stay open, and have no further effect on coolant temperature.  The engine will run at a temperature determined by engine operation (heat generation), coolant circulation (heat distribution), and the radiator (heat removal).

The waterboxer is designed to run at 87 C or hotter, not cooler.  But, if you have an 80 C thermostat, it will open at 80 C.  If the engine is overheating, it will still overheat, and to the same degree.  If there are cooling problems, those need fixed.  I went so far as to get a new radiator, and to flush the coolant multiple times.  Got things straightened out.  However, I did put in a fan switch that turns on the fan at a slightly lower temperature (I think it is 2 degrees C cooler).  It does not make the engine run too cool.

I'm not sure why the 80 C thermostats are available (but there is also a 78 C thermostat, I think).

DMc

---- Ry <rylincoln@GMAIL.COM> wrote:
> Well I got my engine almost back together.  Still waiting on the new oil
> cooler.
> pic(s)
> http://picasaweb.google.com/lh/photo/h0p5TUIV6Ka4grfT1NhzZQ?feat=directlink
>
> the plan is to lift it up and bolt in tomorrow if all goes well I'll be
> working out the kinds by tomorrow evening.
>
> anyone in a hot climate(i'm in Texas) using an 80C thermostat?
>
> peace,
> -Ry