S-Prihadi

Gents,

I was reading and I came to an old TSB, of 2012 in here : https://forums.mbclub.co.uk/threads/...filter.226923/

I am attaching the screen capture because there is a typo I have corrected :




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What I want to emphasize is :
The TSB failed to mention the important fact about M276 oil cap.

This is M276 oil cap.



The important component is inside, the OIL BY-PASS valve.



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Note : As part of 10th years refresh on all plastic handling important fluid. I have installed a new oil cap on my engine.


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M272 oil cap, don't ask me where the oil bypass valve is...I don't know.



This is the best tear down I can get on the net, the M272 oil cap stand pipe. It does not look like oil bypass is there.





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Since M272 oil filter is part of the oil filter housing combo with engine oil cooler, I think the oil by pass valve is inside this combo assy. Those who knows M272 well, please chime in.
https://www.ebay.com/itm/126114777603


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I then look for videos on youtube, hoping to see if anyone made a mistake by using M272 oil filter on an M276 ?
I found one, but its kinda unique.

Video is set direct to 3:45 minutes

So whoever replaced the engine oil and its filter prior to this Mr Sergei video, did the screw up.
However the screw up is unique because how the hell did the guy managed to get a stand pipe of M272 oil filter , which is not sold separately. One must buy the oil filter cap of M272 and cannibalized the stand pipe.
I mean if one goes thru such trouble to procure or cannibalized a part not sold as stand alone, how did he missed the fact that M276 uses different oil filter to M272 ?






Since W212 is getting so cheap by now this age..... I am noticing so many new owners of pre-owned W212 this year alone.
I hope newbie owner of pre-owned W212 with M276 does not screw up their oil filter purchase because many videos lack of mention of engine model.
E350 W212 is what usually mentioned, but not the engine variant M272 or M276.9 .


Okey doky.... M276 newbie owners, don't screw up and buy genuine oil filter only because it is the fleece one, good high flow media.

S-Prihadi

You can push the oil by-pass valve to test its movement. It will sink-in aka open when pushed with your finger.
Can it break ? Sure, it is plastic 100%, except for the spring.






Here is a good video from Chrysler engine. MB and Chrysler was once "sex" partners

Good read : https://www.noln.net/home/article/11...ter-2016-08-01

Good video :



Here is another fun fact. BMW B58 engine oil filter. I really hate plastic !!!!!
Probably due to 2 years recommended oil filter replacement, the plastic internal to the oil filter simply gave up and the oil filter element plastic end cap broke and got stuck at engine side....LOL.
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https://bmautomotivesolutions.co.uk/...uring-removal/


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https://f30.bimmerpost.com/forums/sh....php?t=1624354





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Oil killing plastic is not new actually.....

JettaRed

iTrader: (1)

Let's be clear. The M276 oil filter should look like this:

CaliBenzDriver

and here is the plastic bypass valve...

cost efficient solution


bypass valve itself

When that contraption quits... contaminents are free to plug the oil pump solenoid or shared squirter Cyl. 1+4/5: RIP.

Oil bypass is said to open on pressure differential during start-up and accelerations... how good is the mechanism to positively shut it ?


> Sudden death...
​​I see that BMW aftermarket suppliers upgraded all these cheap plastic parts with aluminum grade... bypass valve and filter cover.
They must had reason to be motivated

​​​​​​I think keeping oil temperature nicely regulated without artificially building extreme heat... can only help.

S-Prihadi

No idea, should be decent but I do not expect 100% leak free integrity. 99% maybe.
It is hard plastic of by-pass valve to kinda hard plastic of the filter element end cap, so it is not o-ring or flexible seal kind of "tight".
The oil filter housing cap is cheap, so every 10 years replace it.... is good enough preventive.

Initially I am more worried about the overall filter housing plastic body aging and cracking more than anything.
60 psi is what it is exposed too I am sure, at cold start and 55PSI when I rev pass 2,200 RPM.... that is a lot for something that big a diameter and at 95C or more temperature.

CaliBenzDriver

I don't understand how that stainless steel spring works to open on pressure difference...

the spring is pushing in the same direction as the incoming unfiltered oil pressure.

incoming pressure is not trying to overcome spring pressure

cleaner oil exits down the filter center.

The other thing is... there are absolutely NO SEAL on top or bottom of filter media between clean/dirty oil.

bottom mating surface


top mating surface

I don't think a clean filter has a significant pressure drop to force a lot of oil through unsealed surfaces.

S-Prihadi

My usual teslong boroscope is not with me at the moment and I do not have new oil filter element to play with.... but this is what I gather thru more inspection.

The big diameter plastic in cyan-green I call Ring 2 will move down together with the center sealing area Ring 1, which has a hole and I believe that is the oil hole.




Thanks to your oil filter element close up photo, the lip elevation ( gap ) is what separate the Ring 2 from the oil filter element plastic end cap and hence Ring 2 can then be pushed upward by differential oil pressure.
So the sealing is done by Ring 1 only.



Since the Ring 1 is like a mini stand pipe and is quite long, maybe 1.5 inch and I can't yet see its side view without my boroscope ,
for now I believe that mini hole within Ring 1 is the allowed opening size for oil flow when by-passed. So only the hole is oil path and not entire size of Ring 1.

Since the oil filter is a pressure fit into the oil filter ALU housing and oil filter plastic cap housing, the Ring 1 will never be out of oil filter element mid bore hole completely, otherwise the oil
filter element will then become loose fit.

The question comes to my mind now is, if the Ring 2 has that oil hole, there must be a way to shut it OFF when the bypass valve is not active.
Otherwise engine will always get some percentage of un-filtered engine oil.

There seems to be some more component in the middle of this oil bypass valve, assuming our M276 design is very similar to this one below you posted, we need to see close up what that is ?



I don't want to damage my retired oil filter cap just yet by removing its oil bypass valve, till I get a new engine oil filter and my boroscope to see its actual movement.
I will update.

S-Prihadi

Got my boroscope back.

I was wrong, the hole in Ring 2 is actually blocked, no flow.





The maximum movement of the bypass valve assy is only 5mm or 0.2 inch.



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So I guess this is the actual sealing region. See its concave/angled shape.



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I think the actual sealing region is very thin, in red. So move up a bit of Ring 2 at 5mm the oil flow will be plenty.


The bottom end stand pipe of the oil filter element itself is holding position when Ring 2 lifts up. So filter element will be firm sitting down and not loose shaky shaky.




The filter element bottom end sealing design is the same as top side. Thin sharp lip.



I guess that is how this oil bypass valve actually works........

CaliBenzDriver

This $50 filter housing is only as good as its inner bypass valve.


thin plastic under stress....
good until its last day, then dirty oil will bypass filtration

bypass has inner spring
The bypass valve has its own return spring


What are chances for survival of thin plastic under spring tension plus extreme heat ??
This filter housing is a smart maintenance item to replace.... I tighten mine by hand, not 25NM. The O-ring seal does not get torqued at all.

S-Prihadi

Get a new oil filter housing plastic cap per 10 years, life is then good
I agree, that by-pass valve is the weaker component most likely.

Plastics plastics.... I sure hate them when they handle crucial fluids at engine operating temperature.