my 190 will get pretty warm if you idle for a long time.....the electric fan will kick on but just keep it bearly off the 120 mark...if you take off it cool back down after a while or if you race the motor up it will cool off to....i never hear the fan clutch engage....even when its really hot, you can pop the hood and the fan is turning but when you shut it off, it continues to turn.....you can take your hand a spin it like its not engaged...i know these cars run hotter than most but i think my fan clutch is bad.....as long as you are running down the road everything is fine

a good assessment. bad fan clutch.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Could be the clutch, but likely the thermo-switch. Wiring varies per year/model, but with ours (1991 2.3) it is the 3 terminal unit behind the thermostat housing. Again with ours, shorting the contacts together in the 2-terminal socket connector while the engine is running clutches in the fan, verifying the clutch itself is good.

Replacing the switch involves removing two other thermo-sensors first. This caused no coolant loss since they are located at the high point of the coolant path. Of course, cool down and depressurize first.

Steve

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'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7

mine is a 2.6.....will this make a difference

Yes, it does make a difference, you have a bad fan clutch. The 2.3 has a main fan that comes on by a thermo switch, yours is a clutch fan. The fact that you have to rev it up to cool down may indicrate that the clutch is slipping.

Same symptoms on my '90 190E 2.6 and just completed the replacement of the visco fan clutch. It made all the difference in the world. When the clutch engages it cools it down 1-2-3. Purchased the part on-line for about $80 and DIY installation went OK with some difficulty. Center clutch bolt is the ball breaker in this equation. You can definitely do it without removing the radiator but I needed about 5 days for my hand to heal up after smacking into the radiator (AKA cheese grater) about a dozen times. Let me know if you are going to do the replacement and I'll give you some tips I used while they are fresh in my head. Also some good information on several posts in this forum.