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I am trying to figure out this leak. it started after my last oil change. I am not sure if I overtightened and deformed the cap or I have too much blow by and it is leaking there. I changed the large o ring in case the first was defective. But I am getting the same result. Basically a fine spray that coats the area.
I really think I have a problem with the crankcase pressure or a related component
I originally had a leak around the ccv cap. I had that changed a few weeks ago. Then soon after changed the oil. So I have been nothing more oil on the engine. Defiantly a spray as it is on the foam under the engine cover.
I also noticed spray spray around this area behind the oil fill cap. I am not sure what it is for It is yje plastic piece with the two hoses crimped to it. You can see the oil collecting on the intake underneath
Pull the filter cap back off and check to see which grove the o-ring is in, it doesn't go all the way at the top of the threads against the lip of the housing, it goes in the groove below that, not an un-common mistake....
Yes. Made that mistake ONCE. It was a messs. I think with the other leak in the last image.there is a pressure problem
haha, yes - i have seen the aftermath of this - owner changed his own oil- installed o- ring on the last groove/ thread (touching the lip of the cap). the seal blew out and the whole engine compartment was sprayed with fine mist of oil. a beautiful mess. o-ring goes on the widest groove/ thread (look carefully- one is wider than the rest) and it does not touch the oil filter cap.
Lol. I am not sure. Probably put wrong sticker on. I always use 229.51. It's an 08 gl320 cdi. Any idea what that plastic piece is with the two lines near injector 1 is for? I have an oil spray in that area. It either from there or the fill cap.
Last edited by smiledr996s; 05-30-2017 at 03:40 AM.
I'm not a pro when it comes to fixing things. Well, I can do the actual "fix" part pretty decently, it's the diagnostic part that requires a lot more experience and education than I have. However, when faced with leaks, a good rule of thumb is to clean everything REAL good, then start the engine and look for leaks. If you don't notice anything right away, go for a short drive and then look again. Repeat with longer drives, if needed. The key is to get everything very clean so that you can easily trace down the leak point.
EDIT: Oh, if you're pretty sure you know where it it coming from, then maybe just clean that area real well. Or secure a rag around the area as you may be able to tell if the rag is getting soaked from the inside or the outside. Just some other thoughts!
Lol. I am not sure. Probably put wrong sticker on. I always use 229.51. It's an 08 gl320 cdi. Any idea what that plastic piece is with the two lines near injector 1 is for? I have an oil spray in that area. It either from there or the fill cap.
That is the fuel line return hose, it has nothing to do with oil. There is an o-ring under that fitting on the top of the fuel injector that will sometimes fail and leak diesel. To remove the fitting, you pull the circular plastic part up (pry very gently with a screwdriver) then lift it off.
Good question. I plan to look into it as I will need more oil in 5k. I am wondering if the 229.51recommendations are because Mercedes just wants to stock limited oil types and the earlier models are having to use what the later models require. With my dpf off I plan to use the best protecting oil. It is just hard to find out with so many formulations.
I changed the oring and it still seaped so I changed the cap and it seems better. But I think most of the oil being sprayed is from a leak under the high pressure pump on the front of the engine. It is dripping on the belt and being sprayed against the area.
The fill cap ? I thought maybe. so I ordered a new cap and gasket. But there is no longer any oil I can see comping from the fill cap as well as the filter now that I changed it out. Unless this is all residual. I will wipe down again and see
The leak is definitely coming from either the high pressure pump and or the oil filter housing gasket. I taped folded shop towel around the gasket to eliminate it as a source. It is hard to tell exactly where it is coming from as it is sprayed by the drive belt. I will probably have both gaskets replaced.
I am hoping that it's not caused from excessive blow by. I would not think as it really does not burn much oil. I don't have to add between 7500 mile changes
05-29-2017, 06:02 PM
