Water Temp Sensor w124
 

For those of us who worry when the engine temp needle goes over 100 degrees, would someone confirm whether or not 006 545 4424 would work in a 1988 w124 to allow the auxiliary fans to come on at a lower temperature than the standard 105/115 green sensor. This part number supposedly is for a 190 engine. Thanks.

I worry all the time when it passes the 90c line... I turn my defroster on and roll the wondows down... I have never let it go as high as between the 90 and 120 mark... freaks me out... coming from a Honda where the temp needle never budges once up to op temp. this is a little scary.

I should probably see if I let it sit and the temp does get higher than I have ever let it if those aux fans come on.

I drive a 90 300ce.

It is 105 degree today. In where I live, climate temp above 100f is nothing. On a hot day like this, My water temp is constantly above 100, it runs even hotter sometimes. I used to worry.

When I went through the debug processes and all the components, I found the prior owner of my 300ce modified the thermostat keeping it stuck open. I put in a new 87 degree thermostat, however makes no change.

I simply take it as normal now.

OK... so you have never actually had it overheat then? It just freaks me out to no end... maybe I should just try to sit with it running in traffic and watch the needle... I'm just afraid it will get too high to the point that the defrost heat will not cool it down in time...

I should prob do a debug too... just for the hell of it.

But does anyone know if the lower threshold water temp sensor for the 190 engine, part # 006 545 4424, will work in the 300e series?

MB engines of the day were designed to run hot. That is just the way it is. They were designed to run optimally in the 90-105 range. Normal down the road should be around 85-95. Stop and go traffic you will see 95-105. The fans are designed to kick in around 100 for normal and 110 for both aux and main. The thermostats are not fully open until you break the 100C mark. Newer MB's stay around 90 all day, but in traffic with the AC my W203 has gotten to about 95, but it has some serious fans on it. Sounds like a jet engine at times. Totally normal for the engine to hit 100.....

There will be no engine damage until the needle reaches the red which is 120.

My particular concern is only in stop and go, when the engine temp will pretty quickly hit about 115 degrees, triggering the aux fans, which work and get the temp down pretty quickly. I just hate watching that needle move up in stop and go.

I had the same problem with my 124. It needed a new fan clutch and a radiator to cure the problem. Now it holds steady. I live in Houston so its important to have good cooling components.