Oil in header tank ? oil cooler or head gasket?

[alf1956]

I have a Merc Clk 270cdi 2005 reg which has been parked up for a 12 month period as it has a gearbox fault which i am eventually going to get fixed & i occasionally run it around the estate where i live & start it up to keep the battery charged up & today i started the car up & let it tick over for around 20 minutes & i noticed a small leak around the top radiator hose which has been like that for many months but not a massive leak more of a drip so i took the hose off & cleaned the metal part up & re-fitted it, i then topped up the water & ran the car for a while whilst stationary on the drive & topped the water up as i had lost some with taking the top radiator hose off & then i noticed oil in the water in the header tank but what is puzzling me is that water that came out of the radiator was pure water with no oil in it at all??? Head gasket or oil cooler? I fitted a new radiator on the car 12 months ago & i have not done 1,000 miles since the radiator was fitted.

 

[joderest]

does this vehicle have the gearbox oil cooler in the radiator ?

 

[alf1956]

I am sure it does

 

[star]

What colour is the oil?

 

[alf1956]

Black as coal !

 

[star]

Then It’s not transmission oil. Could be a number of things, engine oil cooler, head gasket, cracked cyl head or block.

 

[matthew k]

When I had a oil cooler fail on a 530d BMW, it filled the cooling system up with oil at very high pressure. It forced it's way through the pressure relief valve on the resivoir cap.

 

[ajlsl600]

Eng oil cooler likely .least invasive first check if yr a bit workshop handy you ought to be able to take it off and press test it .dont go much over cap press rating tho.. blank one side ,old brass tyre tube valve welded to a fitting that goes on other side of cooler pressurise and dunk cooler/rad in water trough.

 

[alf1956]

I am okay on the tools but what kind of a job is it to remove it & what does the removal entail?

 

[alf1956]

Anybody got any info on what kind of job it is to change the oil cooler please?

 

[mattkh]

Anybody got any info on what kind of job it is to change the oil cooler please?

On a VW, the oil cooler is attached to the oil filter. Put up a picture of the oil filter on your car.

 

[Frontstep]

Look on youtube

 

[alf1956]

Looked already but cant see anything for the Clk270 , some for the ML 270.