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Low motor temperature

1854 Views 8 Replies 8 Participants Last post by  Former Repair Manager
I have MB 190D 2.5 1987 . My temperature gauge never goes over 80C . Strange thing is that my propeller always rotating . Even in -20C . [:(]
Maybe my termostat ? What should I do ?

Many thanks and sorry about my english
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My 1985 190E 2.0 always had a high operating temp. Even during the winter months the temp....

My 1985 190E 2.0 always had a high operating temp. Even during the winter months the temp. guage hits near 100 C when cruising on the highway. I got the problem fixed two months ago and since then the temp. never went above 80 C even if the engine idles in traffic. 18 years old this month and only 30,500 miles on the clock!
I agree , but ...

My car have diesel engine, which I assume need higher operating temperature then petrol engines. Anyway if the outside temperature fall to -10C which is not so cold, the engine temperature is about 50C, even in heavy duty use...
replace the thermostat for a start...

Yep, for a whole 30 euros you can buy a thermostat. A good investment in a diesel where you do want to run at a decent temperature.

Funnily enough I've got the same problem in my 190D 2.5 turbo at the moment. Coming down from a skiing village a couple of weeks ago, it strangely wouldn't get above 50 degrees C. Sitting at lights it's going up to 100! Maybe these thermostats only have a lifespan of 16 years to the day?[;)] (mine's an '87 too)
Thermo problems

I've been hearing many people with 190e's having similar problems (I being one of them), and it goes back to the thermostat. I'd deffinatley have it checked (if not replaced), and at 16 years yours seems to have lasted longer than mine which was 10 years.

Yup your t-stat is stuck in the open position. Get the 87degress type. While you are at it swap the t-stat housing cover w/ an aluminum one.
For the 190E 2.3 there are two thermostats

I replaced the one in my 1993 190E because the engine ran hotter than I liked. With the new one, it rarely goes over 80C unless at idle for lengthy periods.

I have not been able to fine the non-plastic housing.
Where did you buy this?

I am having similar issues with my 2.3. The temperature will sit around here when moving and go even lower at highway speeds. At a stop or when parked the temperature goes up. Figuring the thermostat is stuck open. This photo was taken when the outside temperature was -14C.
Gauge Measuring instrument Font Odometer Auto part
Wondering where to get the 87C type that was mentioned above?
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replace the thermostat and the temperature sending unit
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