Over heating m110 engine

[Magyar]

Hi, all of the M110 powered 280se cars ive owned overheated, why do these engines always over heat?

How do I prevent it from over

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heating?

Is the temp below too high?

[Nabstud]

Mine temp gauge does that but it isn't overheating. It fluctuates between just over 80 and the 100 marks. Often driven in temps over 35°C(95°F) and it never goes over the 100 mark. I've double checked it with a thermo temp gun.
My research suggests W116 temp gauges either never go over halfway or they fluctuate between 1/2 and 3/4.

[mrkozzy]

Anywhere from 90 to 100 on the gauge is about right from memory.
My 280  goes from the low to mid 90's sometimes in the winter.  (This has to do with the "ambient" temperature outside), while in the warmer summer months it generally sits around 90.
Always has done, and I always run it with a quality coolant additive which gets changed once a year.

[Randys01]

 As a   rule of thumb  the "indicated temp" should be about 55C more than the ambient temp.
Now this has a bit of tolerance but no more than 10 % . So at 30 deg C  it should be reading 85Deg C.
Now in heavy traffic on a hot day with a/c on she might creep up to 90s. As soon as you get moving the temp should drop back a bit.
Get yourself a thermal infrared gun and take some temperatures. Make sure what you are seeing on the gauge is largely validated by an actual temp reading.

I find the most interesting is the actual return to the water pump [bottom radiator hose]  and  where the temp sender unit resides. [cyl head ]

There are many reasons an engine can run hot...not just a Merc.. but they all come back to the same thing..........is every part serviceable?
Slipping drive belt..worn waterpump..crud in the radiator..timing out..mixture out..blocked fins in the radiator...dodgey thermostat...blocked radiator hose/s..system properly bled....leaks in the system...brakes dragging etc etc..

 Your photo does not mention the driving circumstance  ie just did  a run down the Tulla freeway at 115 kph  in 30 dgrees C with air on etc?  then I would agree the indicated temp was pretty reasonable.!!
 

 

[Magyar]

As a   rule of thumb  the "indicated temp" should be about 55C more than the ambient temp.
Now this has a bit of tolerance but no more than 10 % . So at 30 deg C  it should be reading 85Deg C.
Now in heavy traffic on a hot day with a/c on she might creep up to 90s. As soon as you get moving the temp should drop back a bit.
Get yourself a thermal infrared gun and take some temperatures. Make sure what you are seeing on the gauge is largely validated by an actual temp reading.

I find the most interesting is the actual return to the water pump [bottom radiator hose]  and  where the temp sender unit resides. [cyl head ]

There are many reasons an engine can run hot...not just a Merc.. but they all come back to the same thing..........is every part serviceable?
Slipping drive belt..worn waterpump..crud in the radiator..timing out..mixture out..blocked fins in the radiator...dodgey thermostat...blocked radiator hose/s..system properly bled....leaks in the system...brakes dragging etc etc..

 Your photo does not mention the driving circumstance  ie just did  a run down the Tulla freeway at 115 kph  in 30 dgrees C with air on etc?  then I would agree the indicated temp was pretty reasonable.!!
 

 

hi, I was doing 110km/h for an hour straight with ambient temperature being 22 degrees c.

[Randys01]

My gut feeling is that it is running a bit warmer than I would like........should be closer to 83 under those driving circumstances.BUT how accurate is the gauge?..AND plenty of other owners would  be satisfied with that. What needs to be told is what happens when the aircon is on and its 35C and you are crawling thru town?
. I suspect she would be approaching 100..too hot.

[rumb]

Isnt the thermostat 87 degrees?  Engine should be near that temp.

As far as running with AC, Though I have only done it on a w126, you can add a resistor to the temp sender that will make the ac fan kick on a bit sooner.  That really helped my 300se. I did also make sure everything else was up to par.