2005 CLK 270 cdi oil cooler problems
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clk270 cdi & c180 ble efficency 1.6 petrol
2005 CLK 270 cdi oil cooler problems
Hello fellow members.
I have a 2005 CLK 270 cdi and I have oil in the coolant and my Grandson advises me that it is probably the oil cooler that is faulty. I have 2 questions which are is it safe to drive 4 miles to the garage & what kind of a job is it to replace the oil cooler?
I have a 2005 CLK 270 cdi and I have oil in the coolant and my Grandson advises me that it is probably the oil cooler that is faulty. I have 2 questions which are is it safe to drive 4 miles to the garage & what kind of a job is it to replace the oil cooler?
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Joined: Sep 2020
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From: Portugal, in the countryside
CLK (W209) 270Cdi 2003
I have a CLK 270CDI too. I never had that problem on it, but I had it on a different car, that has a water/oil heat exchanger, and this is what I would do if I were in your shoes:
First, BEFORE starting the car, check the oil level using the dashboard menu. It is plain stupid why these cars do not have a dipstick...if the dash reports insufficient oil, do not start the engine before adding enough oil. If the level is not OK, it usually says something like "add 1 liter of oil" or "add 1.5liters of oil". Add what it asks, and then check again. This must all be done on a cold engine, on level ground, before it is started.
Second, check if there are signs of oil in the cooling expansion vase. It usually manifests itself as a whitish/light brown foam (for lack of a better word), on the inside of the vase cover, and on the neck of the vase. If the foam is not present, it means that the only issue is loss of oil, and maybe of coolant.
If both checks give good results (oil level sufficient after filling if needed, and no foam on expansion vase), I would drive the car for said 4 miles or so, to a repair garage.
If any of these checks do not come to a good result, or if you find a pool of oil under the car, I would not risk starting the engine at all; I would have it towed to the workshop.
Mind you, if you do not know how and when this started, the engine may already be damaged enough that a repair is needed. These steps are only to avoid causing further damage.
Finally, two questions:
1 - are you SURE that the CLK 270CDI has such a water/oil heat exchanger? I never had to work on that on my car, so I never checked it, but I was under the impression that it had a normal air/oil radiator...but not sure, really.
2- How did you know this was a problem? Was it that the car suddenly reported "Insufficient oil", or some other symptom? It is common the turbo-diesel engines, with high mileages, often loose a little bit of oil permanently, mainly through the turbo, so that, after a good few thousand miles, the oil level may drop enough to trigger an oil level warning. Check the expansion vase, and don't go chasing the wrong rabbit...
Good luck, and let us know how it works out.
DF
First, BEFORE starting the car, check the oil level using the dashboard menu. It is plain stupid why these cars do not have a dipstick...if the dash reports insufficient oil, do not start the engine before adding enough oil. If the level is not OK, it usually says something like "add 1 liter of oil" or "add 1.5liters of oil". Add what it asks, and then check again. This must all be done on a cold engine, on level ground, before it is started.
Second, check if there are signs of oil in the cooling expansion vase. It usually manifests itself as a whitish/light brown foam (for lack of a better word), on the inside of the vase cover, and on the neck of the vase. If the foam is not present, it means that the only issue is loss of oil, and maybe of coolant.
If both checks give good results (oil level sufficient after filling if needed, and no foam on expansion vase), I would drive the car for said 4 miles or so, to a repair garage.
If any of these checks do not come to a good result, or if you find a pool of oil under the car, I would not risk starting the engine at all; I would have it towed to the workshop.
Mind you, if you do not know how and when this started, the engine may already be damaged enough that a repair is needed. These steps are only to avoid causing further damage.
Finally, two questions:
1 - are you SURE that the CLK 270CDI has such a water/oil heat exchanger? I never had to work on that on my car, so I never checked it, but I was under the impression that it had a normal air/oil radiator...but not sure, really.
2- How did you know this was a problem? Was it that the car suddenly reported "Insufficient oil", or some other symptom? It is common the turbo-diesel engines, with high mileages, often loose a little bit of oil permanently, mainly through the turbo, so that, after a good few thousand miles, the oil level may drop enough to trigger an oil level warning. Check the expansion vase, and don't go chasing the wrong rabbit...
Good luck, and let us know how it works out.
DF
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clk270 cdi & c180 ble efficency 1.6 petrol
Hello, yes the car does have an oil cooler as I had new seals on it a few years ago & the symptom's were exactly the same then, oil in the header tank. I know it happened recently as I changed the oil & filter the week before & I found out when I did my oil & water check.
