CLK 220CDI usual running temperature

[Droverunner]

Our recently purchased 2007 CLK 220CDI may be running a bit cool so wanted advice. What is their usual real life running temp? When driven keenly ours seems to read about 80degC on the gauge and a near identical 79degC on the i980 code reader live data which I initially thought OK. But I now notice driven modestly it only seems to reach 75degC.

As far as I can see the stat should start to open at 82degC and not open fully until 100degC.... so I'd have expected a running temp nearer 85+degC.

What temps do others see with these engines?

 

[EmilysDad]

I'd expect more than 75 deg from any engine ... more like the 85/90 that you suggest. I'd look at changing the 'stat

 

[oigle]

Yes, you will need a new stat eventually. Running at 75° isn't going to do any harm for present but it indicates the stat is on its way out. I'd be inclined to change it sometime not too far away. You are coming into winter where heating is required. A better stat will help there.
Ian.

 

[Droverunner]

Thanks guys I'll change it. As it happens I bought a new aux drive belt as routine replacement but haven't fitted it yet as I wondered if the tensioner was worn and a few degrees out of line... so I'd deferred the job from the initial post purchase service.

I think I'll get a tensioner and stat then do it all in together.

I see quite a few folks think the Eurocarparts stat is rubbish... wonder what other make is OK... or is it best to stick to MB... at what cost I wonder?

On Ebay ignoring the no-brands there is a choice of Febi, Gates, Wahl, Behr, Wahler, Valeo. Also some appear to have a sensor fitted??

 

[Wighty]

Thanks guys I'll change it. As it happens I bought a new aux drive belt as routine replacement but haven't fitted it yet as I wondered if the tensioner was worn and a few degrees out of line... so I'd deferred the job from the initial post purchase service.

I think I'll get a tensioner and stat then do it all in together.

I see quite a few folks think the Eurocarparts stat is rubbish... wonder what other make is OK... or is it best to stick to MB... at what cost I wonder?

On Ebay ignoring the no-brands there is a choice of Febi, Gates, Wahl, Behr, Wahler, Valeo. Also some appear to have a sensor fitted??

I bourght a non Merc thermostat from euro cp and had to take it back as it was poorly manufactured fit wise . Paid £17 ish for it , bourght the correct thermostat from MB in the region of £35-40 which fitted perfectly . My Clk is petrol though ! Yours will be more for the diesel I believe .

 

[EmilysDad]

Thanks guys I'll change it. As it happens I bought a new aux drive belt as routine replacement but haven't fitted it yet as I wondered if the tensioner was worn and a few degrees out of line... so I'd deferred the job from the initial post purchase service.

I think I'll get a tensioner and stat then do it all in together.

I see quite a few folks think the Eurocarparts stat is rubbish... wonder what other make is OK... or is it best to stick to MB... at what cost I wonder?

On Ebay ignoring the no-brands there is a choice of Febi, Gates, Wahl, Behr, Wahler, Valeo. Also some appear to have a sensor fitted??

OE or pattern also depends on how easy it is to fit. No idea re your engine, but just ask Lostkiwi about Smart Roadster 'stats

 

[umblecumbuz]

Easy way of telling the condition of the thermostat is not just on max temperature alone, because this can be deceiving.

If your gauge fluctuates between city traffic and open road driving, with the temperature rising in traffic and dropping on open roads, this is a sure indicator of a tired or failing 'stat.

A simple job to change, and worth doing for economy, better heater and engine longevity.

 

[EmilysDad]

Another test is to start the car from cold & monitor the temp of the top radiator hose with your hand. It should go from cold to hot in one go when the stat opens. If it's stuck open it'll get hot slowly.

 

[Droverunner]

Yep it's obviously erratic in operation or perhaps partially open all the while. in the cool air at 9am today it hardly reached temperature until we'd travelled 12mls. Also it does react to engine load and amount of air flowing through the rad in a way it shouldn't.

My BMW diesel warms to temp in a few miles and then holds around 90deg... no different between a gentle run in the winter or sitting in August traffic... always the same.

Be interested in any more 'stat brand opinions.

 

[Yugguy]

I changed the stat on my 646. I used a genuine mb one. They're not that pricey.

 

[Droverunner]

£40... £60... £100 or so??

 

[oigle]

Unfortunately Merc have a bad rep for thermostats. Fail a lot compared to Jap. I bought one from Europarts and it was wrong. Bought OE from Merc and OK. Not too exxy either for my 270 motor.
Ian.

 

[Wighty]

It probably comes down to price , if the competition is very close to the MB part then it's worth paying for the MB part .
In my case by the time I had driven to ECP twice and taken the (non MB ) part back off the car , I had lost most of the day ....all to try and save £20 quid .

 

[Yugguy]

I paid 45 for a genuine 646 mb thermostat.

 

[Droverunner]

Just an update in case anyone looks at this thread in the future with a similar question.

Fitted a new stat today. Looking at live data from the iCarsoft i980 it reaches temp far more quickly and stays in the range 93-95deg.

An example of speed of warming is... we live in a village where it's only a couple of mins to the A1(M). Previously from cold the car just reached 50deg by the time we reached the southbound slip. Now it gets to 72deg and climbing by that point. It's also stopped the business of dropping down in temp as the load decreases in very gentle driving... once warm stays in the 90+deg range.

Info on my stat replacement here... http://forums.mercedesclub.org.uk/i...ant-thermostat-swap-tips.164120/#post-1557512

 

[13enzy]

Yes, you will need a new stat eventually. Running at 75° isn't going to do any harm for present but it indicates the stat is on its way out. I'd be inclined to change it sometime not too far away. You are coming into winter where heating is required. A better stat will help there.
Ian.

Hi
My car had been stood for over 6 weeks whilst i was recovering from my operation
When I finally started it, i eventually realised that there was NO Heat coming in the car !
The engine temperature was sitting at less than 20 degrees all the time, the dashboard was at... -2.0 to 3.0 degrees ......so if i was driving, it would be less than 2.0, and if i was stationery with the engine running it may go up to 4.0 degrees... (and that is still... COLD)
It was suggested by members that my Thermostat is stuck in the open position, and is faulty and will need replacing
I have replaced the thermostat and the engine temperature is now always around 87 degrees (approximately), so this means that my previous thermostat WAS in fact faulty, and the old thermostat had a rattle coming from it too.
HOWEVER....However, although the engine temperature has now gone up to > 87 degrees...... nevertheless i am not getting any heat in the car....Please help...we are freeeezing FREEEEEZIFR !....... As the thermostat has been replaced, i thought it could be an electrical problem, which is not allowing the heat to come through...Hmmmm ...

 

[Andrew Nosbig]

Our recently purchased 2007 CLK 220CDI may be running a bit cool so wanted advice. What is their usual real life running temp? When driven keenly ours seems to read about 80degC on the gauge and a near identical 79degC on the i980 code reader live data which I initially thought OK. But I now notice driven modestly it only seems to reach 75degC.

As far as I can see the stat should start to open at 82degC and not open fully until 100degC.... so I'd have expected a running temp nearer 85+degC.

What temps do others see with these engines?

I also have a 2003 220 CDI. I have noticed recently the fuel consumption increased, especially on cold morning startup.
Usually around 7 to 8 litre/100 , it spiked at nearly 11. A temp check shows water is barely reaching 80 Degrees C. Called Up MB to get some data but it wasn't helpful. Car has 497 000 Km so far. Replaced water pump at 200 k and cat converter at 300k. ( It blocked and car almost stopped naturally)
This model needs Glow plugs all working to clean the CAT.( computer will tell all is ok). Diesel is pumped into the exhaust to burn, raising the temp to 1200 in the CAT and this happened best on a long run (300 Km is a short run in the colony here).
I didn't know my glow plugs were offline...until the computer check showed it.We reset the Data and all came on . Cat was cleaned and engine purrs again.
But the temp issue remains. MB has none here. Has to come form Germany a 3 week wait for 250AUD. Part number is A6462001115.
Looks relatively simple to change it. Fuel is around 6 km / 100 km at the moment ( county drive 110 KM/Hr) . It used to be 4.8.
Conclusion is a warmer engine gives better combustion, and a cleaner CAT. Replace the thermostat.!!
If anyone can direct me to the part I mentioned where to get, be grateful.
Thanks

 

[joderest]

out of interest, my ML270 runs at 80, but in hot weather has run at about 84, dropping back to 80 on a decent run. never goes below 80 once warmed up.
It is slow to reach temperature in the winter, but gets there after about 6 miles. Normal ????

 

[Andrew Nosbig]

out of interest, my ML270 runs at 80, but in hot weather has run at about 84, dropping back to 80 on a decent run. never goes below 80 once warmed up.
It is slow to reach temperature in the winter, but gets there after about 6 miles. Normal ????

Im informed the coolant has a deleterious effect on the metal in the thermostat over time. Make logical sense. 15 years of corrosion with coolant propelled through the aperture would be suggestive of valve incompetence. I prefer to see a warmer engine, better economy , and better for heating in winter. The Mercedes handbook shows temp is about 92 degree ( its a diagram not otherwise stated,) and that the same rating on the thermostat on line I saw. Dont know what is the Manual for your model.