I was actually hoping YOU were correct in it being 90C! LOL....

I can tell you that you should really shoot a Infrared Thermometer around in there and see if yours is off, of at least get the real reading.

I found something recently that no one seemed to comment on that the actual opening of a thermostat is a gradual thing and just starts to open at the rated temp and doesn't fully open for about a 10C range. So that a typical thermostat is not open until around 90C anyway.

There is also a fair number of things I have read about drilling some hole sin the sides of the thermostat to increase the pre-heat flow. But eventually it runs where it runs.

I can also tell you that, so far I have replaced my radiator, coolant, thermostat, temp sender, recovery pressure cap and still I run around 95C to 105C (assuming that middle mark is 100C) on the gauge. But yet when I shoot the hottest are area of the motor, where that coolant it coming out the hottest and its surrounding metal, the hottest areas I can find consistently are from 83 to 91C. So my gauge is lying to me. By about 10C. And I too have seen some hot days, 100F here a few times and it does seem to settle in at that temp. But the REAL engine temp is what I find on the Infrared, not the gauge it seems.

Now, also remember that aux fan is triggered by the AC condenser too.

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1983 300D-Turbo - Deep Blue w Palomino MB Tex (total loss in fire 1/5/09 RIP)
1995 E320 W124 Polar White/Grey Mushroom MB Tex
2005 F150 Supercrew - Arizona Beige - Lear topper
1985 Piaggio Vespa T5 - Black and Chrome

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