How do you read this? Obviously in Celsius. What’s the correct range for operating? I just had my thermostat replaced, radiator flushed, belts checked, and it’s running cooler.
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Read Temperature Gauge
1 reading
Damerel
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Thanks dankly1. Good suggestion to flush the system first. I'll do that and check the thermostat.
Thanks MBGraham. Thrust me, I have been reading this manual like a book in the last weeks.
On the last page here it says: "the coolant temperature might increase to 110C before the viscofan clutch engages".
I'll look at the thermostat first as that sounds to be the more likely cause.
The initial rise in reported temperature is quite usual (mine has been doing it for 30+ years) and there is even a service bulletin which recommends drilling a small hole in the rim of the thermostat to allow a small flow of coolant even when the thermostat is fully closed so as to lessen the rise and to silence demanding customers.
'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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Could you post a copy of that service bulletin? It would be interesting to read just what it says. Was it for a 107 or your 300SL?
I have read an article from a diesel site that suggests drilling a hole could be done as a last resort to overcome overheating, but that then results in slow warm up. Even Diesel giant says: "Now understand that this modification is not a Mercedes fix, it is my fix.". He did it in attempt to overcome continued overheating, not just an initial spike.
If some cars have this problem, but most do not? What could be the cause?
- incorrect thermostat?
- visco fan delay,
- different climate?
- sensor problem?
There are a number of different thermostats available with different temperature ratings. Installing correct one for car might be a start.
Visco fan can be checked to see that it comes on & is functioning correctly. Also covered in FSM. I recall there being different types depending on engine and model year.
'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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15,805 Posts
It looks like this type of discussion has been on BW in past ! I don't own a 380SL and don't know what could be different about it compared with a 350/450SL. But guys in this discussion seem to think so
www.benzworld.org
I found this discussion interesting, just from a technical viewpoint because of my engineering background. But no first hand experience of solving temperature spikes, so will leave it at that
Need help To Modify thermostat
83' 380SL: I read but now cannot located a procedure where you should modify a new thermostat by drilling holes. Can anyone expand on this as I cannot locate the article? thanks a bunch for your help.
www.benzworld.org
I found this discussion interesting, just from a technical viewpoint because of my engineering background. But no first hand experience of solving temperature spikes, so will leave it at that
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5 Posts
My car is CLK 500. In the cool day, it is about 80 C. For summer time with air-con on, it went up to 100 C. The reading on your gage is about 90 C and it is normal.
83 280 SL- 5 speed-The PIG
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40,092 Posts
My old M110 heats up gradually and stops just above the 80 line and stays there.
Going up the Rocky mountains on a summer day...it starts to climb a bit.
Ease off or on the downhill...back to normal.
No AC in The PIG.
Going up the Rocky mountains on a summer day...it starts to climb a bit.
Ease off or on the downhill...back to normal.
No AC in The PIG.
Very obviously the next line is 100. The lines are at 40, 60, 80 and 100.
The are unevenly spaced because the needle indicator movement is not linear.
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3 Posts
I have an ML 350 W163. Thats where my gauge sits also, engine has less than 60k miles ,runs perfectly
This is the link to a good Citrus Flush tutorial from Diesel Giant. Even has lots of cool picturesThanks dankly1. Good suggestion to flush the system first. I'll do that and check the thermostat.
Citrus Flush
Hope this helps!
'72 350SL, '85 300D, '98 E320, '19 Subaru Outback (sold '14 GLK250)
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15,805 Posts
Isn't this the R/C107 sub-forum?
Seems like the subject of this particular thread has attracted MB owners with many different models! This may be caused by that NEW button top right. Doesn't keep discussions within the sub-forum.
Not to say that some of the comments haven't been relevant or useful. MB models of our vintage do have many things in common.
Seems like the subject of this particular thread has attracted MB owners with many different models! This may be caused by that NEW button top right. Doesn't keep discussions within the sub-forum.
Not to say that some of the comments haven't been relevant or useful. MB models of our vintage do have many things in common.
Best explanation I have see so I re-posted it from another web site
"The thermostat on the M119 doesn't fully open until 94 °C (201 °F), and the cooling fan's viscous clutch does not engage until 92 to 100 °C (198 to 212 °F) air is flowing over it (meaning the coolant temperature at the sensor is likely 5 to 10 °C hotter than that).
So, 80 to 100° C is the normal range depending on vehicle and engine speed and ambient temperatures--in very hot ambient temps (we hit 104° F here the other day) the coolant may reach 105° C while stopped in traffic. Without AC on the electric fans will not kick in until the coolant reaches 107° C, and will stop once it cools to 100.
Most newer cars have coolant temperature gauges with non-linear and dampened characteristics that keep the pointer more or less in the center of the range as long as the coolant temperature is within the "normal" range (80 to 120° C on most cars).
Our cars do not do this but instead show the actual temperature as it moves through the normal range--I.e. is is accurate. "
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