Hi all,
So i have had an oil leak from what looks like the cambox seal (has same issue with 2016 B9) in behind the DPF turbo cover area. Anyway due to this i had to top up and noticed a build up oil thicker oil sticking to the bottom of the cap. Wiped it off and drove the car for a bit and when i got back there was oil sticking to it but just ordinary engine oil.
I think it may be oil building up and sticking to it and due to no oil flow in this area it just builds up. My thinking is with these engines having high carbonisation of the oil that the oil up there is dirty and just clinging to the cap. Oil changes are done every 10K and garage has never raised this with me before. It is the first i have ever had the filler cap off so i have no idea what it was like previously. I did notice that the filler has a slopped ledge on it leading in to the rocker area and seems to restrict the flow of anything other than splashes in to the filler area. Car runs fine, sounds fine and appears to be no different than it has been before.
No there is a couple of things that have went on previously that may or may not be part of this.
1) The car from new (June 2020) until April last year was serviced using the same grade as factory fill this was Total Quartz Ineo First 0W30 but after supply issues it changed to same grade C2 spec Comma oil. Now it appears due to issues with the engine this oil was changed from Total Ineo First 0W30 to Total Quartz Ineo First Extra 0W20 C5 spec across all engine models. I found out about this because my usual place could not get me in for a change so i took it to Citroen and they filled it with this. They provided me with an updated service schedule print out and the up to date oil info was presented on this.
2) When the new info about the 0W20 grade came out I believe production scale was not large enough to supply demand at that time so oil changes were done using Arnold Clarks own brand 0W20 C5 spec approved by citroen for use until the new Total grade was available. I am now on to the Total 0W20 C5 as i can buy it at a reasonable price from TMS.
Now is it possible that the changes from different oils have caused some kind of reaction causing this build up?? When i changed from 0W30 to 0W20 i called emailed total and they assured me that there should be no issue when moving to the newly recommended grade of oil. Not to disregard that the grade change may be the issue i am more focused on the change from the Arnold Clark oil to the Total 0W20 as this has been the most recent change. It is going to Citroen in 10 days to have the cambox seal replaced so i will ask them to investigate this but i think i will get another oil change. The last change 6K ago was the first change moving from the Arnold Clark oil to the Total.
I have also seen someone mention that it can be a result of an overheating of the oil causing oil condensate to build up. This is worrying considering these engines get really hot when doing a regen and hot oil seems to be part of the working process of these engines.
I have added a link with the pic of the cap showing a small build up on the cap after my first drive since cleaning the cap off. This stuff was thin and just looked and felt like ordinary splashes of engine oil. Possibly over time it builds up in layers with the thinner stuff running off and the dirtier elements of the oil clinging together.
https://drive.google.com/file/d/1Y8IjgEd...drive_link
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