W221 s350 bluetec oil goes to air filter breather or turbo?

alex_78

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hi

so after few bad experience with deaRership and ripoff indy garage i start take car about my car myself with help of internet and my diy skills :)

i just complete replacing of my oil cooler seals (regardless my car is end of 2011 i still had orange old type seals) during this interesting job i found i also have leak from big orange turbo seal (i replace all turbo outside seals orange and green) so after put everything back together and drive car for 50miles today morning i found tiny drop of oil under car, i remove air intake mainfold and surprise oil again droping from big orange seal (turbo air intake from air filters) turbo itself looks ok rotor is moving freelly without any play on bearing etc) also i don't see oil inside turbo (tiny oil deposit on pipe which goes to intercooler i suspect oil come to air intake by breather pipe and then drop by seal (also my old air filters was dirty in oil) is a bit weird to me coz air go in but looks like at the same time oil go out to air filters...

Today i removed breather/valve and it was some oil in it before i will spend over £100 for new unit i just want to know your opinion is that can be reason why oil goes to my air intake mainfold?

even if is breather/valve is a bit weird coz is only one pipe goes out so even if that want to stop oil is no other pipe to return oil ?
my breather part number is A6420101791

i read on some forum that i can use some silicon together with orange seal on entrance to turbo to stop leaking into wiring below but my concern is that if i block it this oil still will be going either to new air filters or into turbo itself which i guess is not healthy either way

so anyone have any ideas?

is that really can be breather described above? or something else ?
is good idea to use high temp silicone with seal to stop leak?
but how stop oil go there ?

thanks in advance
 

ajlsl600

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breather partialy blocked, turbo seal leaking ussualy see play in spindle. ( not an issue according to OP) if you take oil filler cap off and run motor does it spit oil everywhere, too much cc pressure? reason why oil passing breather back to inlet ? , normally only small or none. check breather,breathers before getting alarmed. failing that some recirculation system that has oil going to it misbehaving and somehow dumping heavy oil vapour in the inlet . OP does not indicate miles on engine , above not likely on low ,average mile motor. and may appear in engine that still has a lot of miles left in it ,in which case one has to seal everything well ,o rings, pipes ect so the oil,oil air mix can get back thru the motor and not all over the floor.
 
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alex_78

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Do you think is good idea to try clean breather? What is best way of cleaning?

I will check later oil cap off and start motor and let you know

Like you said my concern is why breather deliver oil to air inlet?

My car just pass 100k miles mark and is always serviced on time

This amount of oil delivered to air inlet is not massive but is noticable as i said it was drop (1cm diameter like few drops i dont fit engine cover yet after fixing oil cooler) under car after been park overnight also im not sure how much im losing during drive, i guess it can be burned by engine but is propably not good also make engine to use oil a lot

Any other breather in this engine or pipes which i can check ? Apart from breather mention above?

It will be nice (after my oil cooler is sorted) to have fully dry engine ;)
 

Botus

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driven too gently piston rings do not bed in correctly... an element of hard use early in the cars life can have a dramatic affect on this.

As would driving like a girl too often and or using cheap nasty oils and fuel.

we can all pretend posh oils and branded fuel do nothing but its a myth. yes you never notice in the first 4 years and 60 k miles, after that you will. if your rings are gummed up thus don't work and if its was not run in hard enough at the start of its life, the rings will never achieve the seal for good engine performance and oil control you want in later life

a more efficient breather can compensate for these a little, but the merc one is pretty light weight....
 
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alex_78

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Thanks Botus you always repky to mu threads

My car was always serviced at merc dealer or indy with genuine merc oil and filter

Recently i drive mostly in town and as you said gently like a girl even if im big bloke :)

Do you think if last lets say 15k miles was driven fairly gently with some longer trips on motorway (every two weeks or so) i can bring this problem myself?

Sorry if that sound stupid but if i start drive it harder is any chance i can bring it back to normal?
 
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alex_78

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Ok i went to car to check oil cap

So engine was cold

I open oil filling cap then start engine

I notice like oil inside starts rising up till maybe half inch below cap but oil was looking like flat water when is no wind so no spit at all just rising i guess once oil pump start working

I never seen something like that before in any of my cars is that normal that oil go up to maybe half inch from cap?

Also i notice typical diesel noise tapping a bit louder but i guess is ok coz open cap and it was direct noise from inside

Car as i said above just pass 100k miles and drives ok i don’t notice problem with power etc just this oil

Any ideas?

Botus can i drive it like sports car to fix it? :)
 
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alex_78

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Ok i make another looks once is warm up a bit

Is looks like oil not split but kind of circulating also when cap us off is a bit of smoke going from it im not sure is normal

More checks more questions shows up :/
 

Botus

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I would guess cold oil made it look full, if it seems more normal when hot probably OK. Can you find a you tube video or compare to another v6 tractor engine?

But... that said NEVER rev a car hard if the oil level is significantly above max

Pulling the filler cap is a bit hit an miss, unless you can compare to another which you know is OK you won't gain much.

Engines are designed to be a closed set up for emissions, pulling the filler cap can make them run odd because all of a sudden you have the wrong manifold vacuum etc. Then you need to realise the oil is meant to be flung around to lubricate the camshaft, cam chain and valve gear. Depending upon how enthusiastically the engineers designed this oil movement, the temperature, the grade used, the age of the oil, the impact of the breather now being compromised and revs, the amount spitting about will vary between anyone of those conditions. And after all that, at tickover, unloaded, the amount of leak by on a piston ring should be insignificant unless the engine is totally trashed.

One could try something to clean up and un-gum the piston rings and when everything's ok and fully warmed up exercise the car regularly and see where that gets you. The other idea would be a compression check or (and I don't know if tractors can do this, but on modern stuff probably) a diagnostics session can measure how hard its working by dropping one cylinder at a time and measuring the drop in revs.... it should then spit out data if its doing roughly what the manu thinks it should be on each cylinder....
 
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