kistiyanpetrov

engine odometer is 121k km
since unplugged 2k km
im running on stage 2 if that matters

CaliBenzDriver

Ok, the first thing is to avoid rushing to higher viscosity oil on stuck rings that's going to get pre-ignition LSPI damage.

Burning thin 0w40 gas-saving ZDDP based SAE-SN oil for 120k.KM guarantees your piston rings are anywhere from dirty to jammed.

You can simply assess the rings condition by how much oil the engine is consumming and how unbalanced is the engine shaking at 1000.RPM.
If you like numbers you can measure compressions or test relative compression.

Once you're satisfied with your engine conditions, gradually upgrade viscosity up to what you're satisfied within 15w40; 5w50; 10w50 in SAE-SP safer anti-LSPI chemistry.

Leave legacy SN chemistry behind and don't switch back and forth SN/SP/SN. Stick with better cleaner thicker SP chemistry.

Expect your engine to gradually seal as burnt oil quit accumulating with spray-cooled pistons. Some patience required.
You'll notice engine response improving as cylinders balance is restored. Rings blow-by losses will normalize.
This should get nice results in 10+KMi using normally detergent oils.


> THE KEYS ARE... :
-- When oil stops burning, it starts cleaning!
-- How do you know... it stays amber instead of black!
-- Stable viscosity also enables ECU to learn VVT PWM positioning
-- Results are directly linked to oil viscosity
-- Don't rush or skip viscosity steps

-- > Read MOD-0;1;2;3;4 :
Is that a clear enough roadmap for your self-improving journey?

kevm14

This applies to a lot of vehicles but generally not Euro vehicles which all seem to have oversized sump capacities for this reason. Many engines are known to starve the oil pump pickup under sustained high RPM use, especially if you add cornering loads. Nissan VQ is just one example.

W205C43PFL

I see, so does it apply to our engines at all, we need to overfill the oil beyond the max line? Since it is a Tasos video and how he works on MB engines, I would assume the video is to be about MB engines?

kistiyanpetrov

thanks for your feedback, well from what i see the 5/40 and 0/40 (current AMG oil) that im using both are SAE, so in the link you provide you're saying this
"- Upgrade older SN oils to API SP rated formulation"
is that means i have to look for oil that is API SP instead recommended SAE?

so next change will be with 5/40 again for sure but question is with which oil (would appreciate if you recommend), after that i will think if i would jump the viscosity a bit as you mentioned

CaliBenzDriver

I currently don't know of any good SAE 5 or 10W40 with API-SP chemistry.

Back then I used the Motul 5w40 SN recommended by @juanmor40 that had a good enough viscosity to spray my pistons cool for 2000Mi.

Then I had to boost it with 600ml shots of 15w50 SN. That experimental "7w44 blend" held up cooling without burning.
This is what motivated me to venture away from the limitations of "MB Approved" low viscosity gas-saving oils.

Can you find an SAE-10W40 API-SP or SN as well since I guess you are currently still running an API-SN oil that relies on high ZDDP chemistry.

The current oil I run is a Valvoline 15W40 API-SP: it lubricates well holds up to the heat without shearing out.
Its API-SP boron chemistry has got my engine heads quieter including the HPFP is now smooth quiet... the engine hums!

I still want to try a Motul 5W50 SP to see how it compares at removing pistons heat at driving RPM.
My logic is if "15w40 viscosity is high enough then a 5w50 should make no improvement".
​​​​​​✌️

W205C43PFL

Motul is good but could also try Pennzoil.

CaliBenzDriver

Of course Pennzoil makes great lubricants.
Do they sell: 15w40; 0w50; 5w50; 10w50 in API-SP ?

My M276-NA testing shows the threshold for spray-cooling my clean pistons at driving RPM is near a 15w40 viscosity.
​​​​​​Viscosities above are practical insurance of stability under higher TT heat... 0/5/10W50 API-SP.

You'll soon realize that all viscosities are not available. Only a few niche applications are covered.
High ZDDP "racing oil" is not compatible with cats + lambdas!
Nascar redline engine oils have nothing to do with spray cooling at 1500.RPM.


> Defining the Limits:
-- Somewhere above I noted "when oil stops burning it starts cleaning"... that's the setup you want for everyday motoring.

-- The right viscosity for your application is the oil that stays amber by spray cooling pistons.

-- Extremely overheated oil burns into carbon, jams pistons rings that cause high blow-by losses and unbalanced detuned engine.

W205C43PFL

I see.

kistiyanpetrov

hmm really no idea the 5w/40 and now the 0w40 amg oil if they're API-SN at least i can't see anywhere on the bottle to be labeled as "API-SN" so not sure how I can find what actually is.. btw which Motul you have used as I find two of them Gen 2 and non Gen

I was thinking a while ago for that as well as I read somewhere that someone was very happy with it, but still using MB one even when i service by myself due the Service interval at MB dealer.. also Amsoil someone was tell me that is good but i don't know anyone that used it before to share feedback

juanmor40

Here is the link to Motul page, you can see all the specs

https://www.motul.com/en-US/products/17603

W205C43PFL

That was forum member JettaRed, he personally has it (Pennzoil) in his vehicle.

I personally prefer Motul but that is just me. The Pennzoil is also a very nice option.

CaliBenzDriver

I side with Lake Jr when he says "oil brands don't mater!"
All synthetic oils are good, some are better than others.
A well priced Motul 5w50-SP is still going to spray-cool better than any super-premium 5w40 gas-saving oil....

API-SP lubricants use the same Lubrizol boron additives package. The old 1950 ZDDP has just about run its course!

The big difference is the base stock that you can read about in specifications. Get used oil analysis looking for bearing metals or simply use proven dynamic film as protection...

-- Good stocks stay in range unaffected by heat.
-- Cheap blends shear out of range in a hurry...

Define your target viscosity and find who blends it for the price you like, 2 Gallons at the time.


Welcome cool engines... sealed with clean oil if you so desire.