Hi all, So I completed my initial oil change on my 2013 E350 Base V6 yesterday. (73000 miles)

I have a couple of questions.
(1) the oil was really black, like diesel oil black. Is this normal? The service reset was reset about 800 miles ago, before I bought it. The oil on the dipstick was so black I decided to change it, as I didn't have any confidence in it.
Anyway it just seemed abnormal.

(2) I watched a lot of videos about these oil changes, and they all show the oil filter cap being removed and no spillage. So I pulled mine off not really thinking there would be an issue. I also have a VW TDI with the same sort of filter cap and this is how I do it with that car. I never spill more than a drop or two.
What a mess. I had oil on the serpentine, and all over the front of the engine. It took me forever to get it all cleaned up.

So what is the trick Do I open it a little and wait, How do I avoid making such a mess?

(3) I also checked the air filter and I had a little bit of oil in the bottom of the oil filter box. No more than a tablespoon. I cleaned it up, and read a bit about oil in the airbox. Seems the PCV is going bad? I have a slight vacuum on the oil cap. Enough that I can feel it when I take the oil cap off if the engine is running, but not enough to make it difficult.
So How much oil in the airbox is normal? (None, a little)?

Thanks for the guidance.

 

Good questions.... never mind the airbox oil, the real oil pool is in the intake plenum: 1Qt.
MB has a sort of plastic catch can between airbox and throttle body to collect overflow from the intake.... empty that.


As far as the oil being diesel looking... that is a real issue. You need shorter intervals 6KMi change and use high-temp premium 10W40.

The issue is these engines use a managed oil pressure that prevents lubricating pistons during low pressure below 3500rpm. Friction overheats the moving parts that FLASH VAPORIZE THE OIL through PCV breather into intake, onto unsprayed valves and coats lambda/O2 and cats sensors.

You'll notice this engine has an appetite for drinking its own burned oil through intake (not so much piston rings).


Recently my 50kMi M276 has stopped burning and drinking its own oil and running so hot. I noticed because car has always smelled like a giant oil leak was burning over muffler - I got used to clunker smell. What's even more odd is the oil color shows it's not burned black.
I attribute that to the injectors switching to a low toctoc instead of high tictic after entering closed loop. That's still very new to me... still learning!

Enjoy your ownership.

 

Oh that really good to know, I'll look for it and empty it.

I was already planning on keeping the interval to 5k.

It will be an adventure I'm sure, but thanks for the pointers!

 

As far as I know, oil color could be black which means oil just doing its job : to clear the particles inside the engine and removes dirt but if it's extremely as black as diesel oil then it might indicate some issues as well . I'm not a member of DIY Club so I can't say on other things about oil , filter changes .
Happy Driving

 

Yeah Normally with a gas engine the oil will move towards black from caramel colored over the course of it's life. It's sort of a visual indicator of how dirty it is. Where as with a Diesel engine the oil will go almost completely black within an hour of being put in the engine.

My oil just seemed particularly black, so probably it was just over due for an oil change, but the service reset just a few hundred miles ago sort of threw me off. Maybe the previous seller just reset it to give the appearance that it had been serviced.

 

My habit is to warm the oil to operating temps before changes. Then I crack open the filter cap just a half turn or so, simply to break the seal and encourage any oil to drain into the oil pan below. I let this work while I prep my oil evacuation pump. I've never had any oil present once I later remove the cap completely.

I've used Mobil 1 0w40 for years. It's always a thin black color on removal, whether at 5K removal or once every year. Seems perfectly normal to me.

 

Oil on gas MB engines usually keep brownish color before call for service, so black oil is not a good sign. I would send it for test.
Now you cans start a topic about sellers resetting the service meter without oil change.

 

I would also investigate checking the oil separator and drip pan, the part of the PCV system at the rear of bank one, or the right head. Easy test, with engine running loosen oil filler cap and observe the amount of vacuum in crankcase higher vacuum the less effective the separator is, also if oil dipstick sometimes appears to have raised from dip stick tube, a bad oil separator is why, but these are not guarantees the condition of separator, oil in plenum is an indicator. The separator has a seal that will allow oil into intake system due to hardening and shrinkage of said seal. Downside, the HPFP must be removed to change these parts as one bolt is covered by the High Pressure Fuel Pump.

I would do an oil analysis to know condition of engine, they can also advise on oil change intervals optimal for your engine. There are videos for Blackstone oil testing for better understanding of the benifits and process.

I'm old school, so I change mine too soon, 6k. But I know my engine will outlast me at this rate. My 04 Jeep WJ oil tests are the same as an engine with well under 100k despite having a quarter of a million miles on it.

 

I don't think the PCV system is responsible for burning or not burning oil black. It's doing a poor job at condensing oil droplets that end up puddling in the plenum.

Here is the dipstick of my engine on best behavior. The oil light color is far from black tar.


great looking unburned oil (dipstick not blackened)

My oil used to turn black in less than 500Miles. This oil is over 2000Mi with city and mountain highway speeds (Reno/Tahoe, Nevada). M276 RPM mostly below 3500Rpm.

I think the Bosch ECU is involved in these results... TIMINGS do MATTER.

With normal oil viscosity comes better VVT pressure control by way of the 4x solenoids.

The whole theme about "No CEL, No Code, No Problem" is not serving MB owners.
🤞

 

Oil separator and drip pan...
I'll have to dig into this deeper. I did a quick search and it looks like the PCV valve is also known as the oil separator cover.. Is that right? Or is this the actual Oil separator? "Mercedes Engine Crankcase Vent Valve - Genuine Mercedes 2760100331" & "Genuine MERCEDES Oil drip pan 2730100162"
I do have a slight vacuum at the oil cap, enough to feel when opening the cap, but not enough to make it difficult to remove, and I did notice when I first purchased the car that the oil dipstick was not fully seated, like the pressure had pushed it out past the o-ring. After I checked the oil the dipstick has remained in position. There is one Youtube video that describes this process pretty well, not a quick job, but I've added it to my longer term list. I'll probably do that and the sparkplugs at the same time.

Since changing my oil and putting 100 miles or so on it, it is still a nice amber color, so I think it was just overdue.

Thanks for your help, I didn't know about the drip pan part.

 

So I'm not sure I understand what you changed, Is the Bosch ECU an upgrade? I thought the original is Bosch. Thanks for jumping in!

 

No doubt Blackstone is probably a good idea

 

Thank you, I'll try the half turn next time. I hate to make a mess if it's avoidable.

 

I change mine in both cars every 5k miles, just because. it's dirty enough to actually read on the dipstick, but not black. you should get a new o-ring for the dipstick included with the new oil filter.

 

Does anyone know how our smart dipstick works to be stored dry and get wet once reinserted down the tube?

There must be some kind of weak spring that slowly brings back out/up the dipstick... perhaps helping it pop up ??
My dipstick shows a slight curve. I am going to guess there is one way it is best inserted so its curve faces: front/back or sides.

 

Color isn't an indicator of oil performance, sometimes its cooked, sometimes the engine is running super clean because all the particulate is in suspension. For oil change interval youd need to do like 2 back to back UOA's with the same oil and OCI to make sure everything is cleaned out and thats how it's running. Diesel oil looks like **** all the time but it can get run out to 50-60k when using a bypass filter that filters down to like 5 microns. Also as much as people hate to admit, different oils do different things despite all of them being approved for use in the car. They all had different ways of achieving an oil resisting viscosity changes, oxidization, and acidity with different blending of base oils and Lubrizol add-packs.

If theres a ton of black in the oil, could just be that the engine is running really clean and thats just where your engine keeps all the soot. The filters also play a huge part in this so make sure you use the good ones like Mann/Hengst/Mahle/Wix.

The thing that tells you how an oil is doing is how it feels, how it smells, and how much TBN and wear metals are left in your oil at your particular oil change interval. When your oils is starting to go it's ability to resist cooking off and thickening starts to give out long before it becomes acidic and real damaging but basically if theres ANY TBN in the oil, it's doing it's job resisting acidic, but it's viscosity changes are why we have to change it.

As for how to avoid the spillage, you just pick up the oil and put it in a parts-bowl. The car is supposed to drain for like 15min though, and the first step to an oil change is popping the oil filter out anyway.

I sell these kits if anybody wants to get into the rabbithole of "oil".

https://www.amsoil.com/p/oil-analyze...it/?zo=7236674

 

Now that's a damn good question Cali, I always wondered about that. My seven previous Benz's didn't do that!

 

Agreed, It doesn't make any sense to me.

 

No doubt, if it were a diesel I wouldn't even think about the color, but it just took me by surprise. The fresh oil change I put in it seems to be acting normally thought I only have a couple of hundred miles on it at this point.

I've run bypass oil filters on several vehicles, but I'm not sure I'd know where to tap it or put the filter housing on this thing. Everything is so tightly packed in the engine bay. Have you put a bypass filter on one of these cars? if so where did you put it?

 

Yes, the cover has a seal, once removed the drip pan, doesn't look like a pan at all, can be accessed. But, one of the bolts holding the separator, or cover is blocked by the High Pressure Fuel Pump, this will need removed first.

 

Agreed on the diesel oil, I had a car with black oil, I changed oil 4 times within 2k used a liter of kerosene and ran at idle 10 min, before dumping oil while hot. then changed next oil at 1k, then 2k, I changed the oil every 3k it never turned black again. Oh, I changed the oil filter every 500 miles till the 3k oil change intravils. Now you can get a BG oil flush service for about $300 to flush sludge out of the engine, that is why the oil turns black so fast.

 

Lots of oil in the filter housing is not normal. When I change my oil and filter, I unscrew the housing cap and take it out immediately and there is just a spoonful of oil in the low corner inside that cannot drain due to the shape of the housing. Your filter had to be quite seriously plugged to hold lots of oil in the housing after engine has been shut for several minutes at least. If the oil was changed just 800 miles ago then perhaps that is what was done only not changing the filter?

Oil being overly black after only 800 miles would be a concern to me but perhaps wrong kind of oil was used? I change oil every 5000 miles (filter 10000 miles) and my oil is so clean I can hardly see it on the dip stick. I have always used Mobil 1 0W-40 oil that is recommended by the car's manual.

 

My E250 diesel doesnt turn oil black for about 1k miles and even then its various grades of getting darker. My truck cummins no emissions takes a good 3-5k miles if I remember correctly to start getting pretty dark. I change the oil in that thing every 15k miles and use dyno oil for diesels in it.

Anyhow as noted before color of oil usually isnt indicator but lab test and such are. Few other tricks but none that are very precise.

 

Agreed, but I do know heavily sludged engines turn oil black fairly quick, just depends on how many oil changes were missed, and how long. We had a customer who bought a Town Car that had 100k on the original oil, he claimed the original owner never changed oil just topped off with whatever the station had, and occasionally changed the filter. Oil pressure was low but not bad, compression low but within tolerance, so we performed a BG oil system flush, he changes oil every 3k with 10w40 Mobile one and Slick 50, Snake oil in my opinion, Oil was never black again for as long as I worked there.