Normal Operating Temps
 

'92 300SE. Just getting used to the car and I'm wondering what operating temps are normal. Weather here in Houston has been cool of late, so don't know how the #'s will look during the hot and humid days of summer, but...

On the freeway @ speed - 85C. Stopped in traffic or just after exiting freeway and coming to stop - 95C. Car cools back down to just under 90 at local road speeds.

These temps are with climate control off.

Does this sound about right?

Of course starting with the "newer" engines in 1984, MB designed engines to run at hotter temps than before.. the average thermostat opening happens around 90C. so any temps in that area are normal..temps around 110C in the summer are also normal.


Emissions & emission controls seem to function better at higher temps..

have even seen some real late engine designs that operate at 120C.