i noticed today that while stuck in traffic my temp was running up to 110 or so. i sped up and temp dropped to 85, then it went back up when stuck in traffic again.

i only saw one big fan (not 2) that ran very slow but continuously. i don't think it ever stops but i'll check tomorrow. the old owner glued this fan together which could be why it's running so slow. or do they all run slow? in other words, is this normal?

the fluid was just a bit low but not too low, which could be the cause of overheat. but i just can't see how this slow fan can cool down anything.

please note that i didn't want to wait until the car went to 120+ and steam up so i shut off the engine. so it didn't technically overheat, but it was running hot alright. i just felt that the fan should've kicked in high gear at 100 which it didn't.

does the fan run slow and then kick in at 90+ or how does this work?

i guess my other question is; at what temp does this car start steaming? i'm sure it went up to 110-115. i shut it off just a hair below 120.

Are you talking about a 190E 2.3? or 2.5?

Are you talking about the fan on the inside of the engine bay attached to the engine? Or is it mounted on the outside of the engine bay on the radiator/ac condenser?

There are many model and each will have a different style of fan.

If you've got the 2.3, the engine side fan, then you've got a magnetic clutch style fan. The fan should kick on at a certain engine temperature. You should be able to trip the sensor to test and see if it works. I'm not certain of the sensor location so someone else will have to chime in. If that fan is not working then that might be a cause of part or all of your problem.

If you've got the 2.5 diesel, the engine side fan has a liquid clutch that will engage when it reaches a certain temperature.

The outside fans mounted to the a/c condenser have a dual purpose. They have a low speed that kicks on when the a/c system reaches a certain pressure and they have a high speed that kicks on engine the cooling system reaches a certain temperature (115-120C I believe)

Normal operating temp is just at 80C for these cars.

Either its your radiator clutch fan, radiator itself, or possibly the water pump.

Whats the engine normal operating temp?
Whats the engine temp at speed/on the freeway? with the ac on?

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Thanks,

it's a 2.3. i took a closer look and the outer fan never comes on. the clutch fan does kick in but only at 120C. in other words, when stuck in traffic, it goes up to 120C before the clutch fan kicks in to high speed. then it cools down to 95-100, if still in traffic it'll go back to 120C and repeat. when able to speed a little; it'll go down to 95C or so. if able to do 40mph+ it'll go down to 85C.

so how do i prevent it from getting up to 120C? the radiator has been replaced. it's not the water pump. not the switch. my a/c isn't working so probably why the outer fan (a/c fan) doesn't come on. puzzled here....

thanks again