Hello again,

I just wanted to find out if it is normal to have the temperature gauge pointing to high temperatures in this hot weather. The gauge usually has the needle a little under the 120 degree mark. Also, is it normal to have the clutch fan, when on, reduce the performance?


Regards,
Asim

In hot weather the engine temps run around 100C. However MB doesn't turn the overheating switch on for the AUX fans until 107C. So I would say under 110C would be normal!

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In blazing hot Texas, my 300E (now outfitted with all new cooling system components) runs on the highway between 85-87C, and around town at around 90C. May climb to 95C if stopped at a long light.

If I am running errands (stop, engine off, sitting in hot weather for a few minutes, then restarted), temps will increase to 100C, but never more than about 105C. I guess since the fans don't run when the engine is off, the temperature gets to climb a bit, since the coolant is no longer circulating.

BTW, these figures are with the A/C at full blast.

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