NOAK evaporation and GDI engines

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Originally Posted by wolf_06
https://www.youtube.com/watch?v=xrLNDgrIw3U

I was watching this video, and as a owner of a direct injection car, 2018 Mazda 3 that I got brand new, now at 40,000 km, I realized how direct injection is an amazing technology, but seems to have his flaws.

So this guy seems to say that to have less evaporation going in the PCV valve and being recycled in the intake and sucked back in by the intake valves, which is where they apparently get gummed up, to use a oil with a lower NOAK evaporation, basically that wont evaporate as quick so it doesn't end up gunking up the intake valve.

That being said, he also mention that a 0w20 or a 20 weight oil will evaporate quicker and gum the intake valve more. The 20 weight oil seems to have higher evaporation %. His opinion is to go with a thicker oil that will have less evaporation, less crankcase gas, less gunk on the intake valve.

So basically a top quality low evaporation synthetic oil in a 30 weight, 5w30 or 0w30 would be ideal for GDI.

He didn't mentioned anything with quality of fuel, octane ratings, detergents, so basically 87 octave vs 91 or higher.

In my manual, Mexico recommends 5w30 at a 5000 km OCI, with no real specific mention of a synthetic oil. Maybe, just maybe a low NOAK dino oil changed at 3,000 miles the old fashion way would prevent this? Or a good synthetic low NOAK changed at 5,000 miles.

Any of you had problems with direction injection like this? Needed a valve cleaning service?

Or course the dealership will jump on this to make money.

Another thing, who knows what kind of oil the dealership puts in my car, they say its Petro Canada 0w20 full syn, but who really knows, they want to make a profit, not really caring for my intake valve IMO.

I would appreciate your inputs on this, Thanks!

It's Noack -- the last name of the scientist who invented the procedure.

I've been saying this over and over: It is not distilled evaporated-oil vapor that comes from the PCV and deposits on the intake valves -- it is liquid oil-mist droplets that contain the whole additive package with ash. Therefore, Noack does not directly affect the intake-valve deposits (IVD).

However, the base-oil quality does affect the IVD, and the Noack is inversely proportional to the base-oil quality for a given base-oil viscosity. For example a PAO-and-AN-based oil like Mobil 1 Extended Performance 0W-20 (not the other viscosity grades) or a GTL-based oil like Pennzoil Platinum with PurePlus (all viscosity grades) will help. Nevertheless, you won't see a difference between PPPP 0W-20 and PPPP 10W-30 even though their Noack's vastly differ, as their base-oil quality is the same.

The following all help: lower sulphated ash, higher base-oil quality, more antioxidant, and (possibly) less VII. Noack does not directly help.
 
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3-4k oil changes with Pennzoil YB 10-30 is what I'm running in my GDI (at least in the summer). Noack under 5.
 
Originally Posted by Whammo
3-4k oil changes with Pennzoil YB 10-30 is what I'm running in my GDI (at least in the summer). Noack under 5.




Is that the latest Noack reading?
 
Originally Posted by PimTac
Originally Posted by Whammo
3-4k oil changes with Pennzoil YB 10-30 is what I'm running in my GDI (at least in the summer). Noack under 5.
Is that the latest Noack reading?

Exactly. That test with Noack ~ 4 was done five years ago. It was probably an unusual surplus GTL base stock that was used. The current formulation is likely to be of Group II or Group II+ with much higher Noack. You are much better off with a synthetic oil you're sure to be of Group III, GTL, or PAO, as the base-oil quality is what matters for IVD, not the Noack, as I explained above.
 
Originally Posted by tc1446
Would a Catch Can help?


Good question. I've read a lot about catch cans and as of now, have concluded that they are useless. however part of me still thinks they may work ... lol

Having said that, I never used one and the last time I checked the pcv valve and the connecting hoses, etc. in our 2.4L GDI (iirc 70K miles at the time), I did not see a drop of oil or sludge or gummed up oil or nothing. Very nice and clean.You would think some oil should have condensed in there ... I thought maybe fuel due to dilution is washing things clean. idk. Was expecting some sludge or residue.
Btw, since the valve was nice & clean and clicking ... I put it back.
 
Originally Posted by Gokhan
Originally Posted by wolf_06
https://www.youtube.com/watch?v=xrLNDgrIw3U

I was watching this video, and as a owner of a direct injection car, 2018 Mazda 3 that I got brand new, now at 40,000 km, I realized how direct injection is an amazing technology, but seems to have his flaws.

So this guy seems to say that to have less evaporation going in the PCV valve and being recycled in the intake and sucked back in by the intake valves, which is where they apparently get gummed up, to use a oil with a lower NOAK evaporation, basically that wont evaporate as quick so it doesn't end up gunking up the intake valve.

That being said, he also mention that a 0w20 or a 20 weight oil will evaporate quicker and gum the intake valve more. The 20 weight oil seems to have higher evaporation %. His opinion is to go with a thicker oil that will have less evaporation, less crankcase gas, less gunk on the intake valve.

So basically a top quality low evaporation synthetic oil in a 30 weight, 5w30 or 0w30 would be ideal for GDI.

He didn't mentioned anything with quality of fuel, octane ratings, detergents, so basically 87 octave vs 91 or higher.

In my manual, Mexico recommends 5w30 at a 5000 km OCI, with no real specific mention of a synthetic oil. Maybe, just maybe a low NOAK dino oil changed at 3,000 miles the old fashion way would prevent this? Or a good synthetic low NOAK changed at 5,000 miles.

Any of you had problems with direction injection like this? Needed a valve cleaning service?

Or course the dealership will jump on this to make money.

Another thing, who knows what kind of oil the dealership puts in my car, they say its Petro Canada 0w20 full syn, but who really knows, they want to make a profit, not really caring for my intake valve IMO.

I would appreciate your inputs on this, Thanks!

It's Noack -- the last name of the scientist who invented the procedure.

I've been saying this over and over: It is not distilled evaporated-oil vapor that comes from the PCV and deposits on the intake valves -- it is liquid oil-mist droplets that contain the whole additive package with ash. Therefore, Noack does not directly affect the intake-valve deposits (IVD).

However, the base-oil quality does affect the IVD, and the Noack is inversely proportional to the base-oil quality for a given base-oil viscosity. For example a PAO-and-AN-based oil like Mobil 1 Extended Performance 0W-20 (not the other viscosity grades) or a GTL-based oil like Pennzoil Platinum with PurePlus (all viscosity grades) will help. Nevertheless, you won't see a difference between PPPP 0W-20 and PPPP 10W-30 even though their Noack's vastly differ, as their base-oil quality is the same.

The following all help: lower sulphated ash, higher base-oil quality, more antioxidant, and (possibly) less VII. Noack does not directly help.



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The following all help: lower sulphated ash, higher base-oil quality, more antioxidant, and (possibly) less VII. Noack does not directly help.[/quote]

Can you educate me on lower sulfated ash? Im not sure about that, and what oil would you suggest?

Is runner regular vs premium gas would reduce some deposits through the pcv?
 
Originally Posted by wolf_06
The following all help: lower sulphated ash, higher base-oil quality, more antioxidant, and (possibly) less VII. Noack does not directly help.


Can you educate me on lower sulfated ash? Im not sure about that, and what oil would you suggest?

Is runner regular vs premium gas would reduce some deposits through the pcv?[/quote]

The Ravenol cited and many 504/507 specification oils have the wanted attributes as pointed out by Gokhan. A good detergent in the gasoline is desirable for many reasons.
 
Sulphated ash (SA) is usually listed in the oil specs. It's a method to determine the ash (metal) content of an oil. Ash can deposit on the intake valves, spark plugs, oxygen sensor, catalytic converter, particulate filter, etc. Typical ILSAC oils have 0.8% SA, which is also borderline mid-SAPS (SAPS: sulphated-ash, phosphorus, and sulfur) for ACEA oils. VW 504.00 oils mentioned above also tend to have 0.8% SA.

With direct injection you're not getting much gas on the intake valves if at all. The detergent content of the gas is usually independent of the octane number.
 
I'll be running Mobil 1 0w20 EP or AP in my GDI engines. Majority PAO/AN with a SA of .8. I think that's the best choice among any readily available oil. The only other oil that may be better would be Driven GDI oil which is using mPAO and has a SA .72.

Have to give XOM credit they were 7 years ahead on this.
 
Originally Posted by Gokhan
Sulphated ash (SA) is usually listed in the oil specs. It's a method to determine the ash (metal) content of an oil. Ash can deposit on the intake valves, spark plugs, oxygen sensor, catalytic converter, particulate filter, etc. Typical ILSAC oils have 0.8% SA, which is also borderline mid-SAPS (SAPS: sulphated-ash, phosphorus, and sulfur) for ACEA oils. VW 504.00 oils mentioned above also tend to have 0.8% SA.

With direct injection you're not getting much gas on the intake valves if at all. The detergent content of the gas is usually independent of the octane number.


Gokhan, it seems only Mobil 1 has a SA of .8 among the readily available PCMO's. Vavoline is at .97 and Amsoil is well over 1.1. Not sure about Castrol and Pennzoil. They don't report it. Castrol I feel had issues with their Edge EP which is why they could never meet dexos 1 gen 1 if I had to guess.
 
Originally Posted by Ignatius
Originally Posted by Triple_Se7en
I think the OP wants to know what the lowest Noack oils are in 5w30?
In the mid-priced, I think Mobil-1 has two...... AP and ESP. Valvoline may have two.... Modern Engine and Advanced. Pennzoil Ultra Platinum may be on the low tier also. Same with Rotella Multi Vehicle.
Anyone care to add to this, or eliminate any of the ones I suspect are pretty good Noack oils in 5w30?

Valvoline Advanced Synthetic 5w30 is 8.0 NOACK. Outside of maybe Ravenol it is the lowest 5w30 NOACK I am aware of.

According to Valvoline's product info sheet for AFS, the 5W30 has 9.3% Noack loss...the 10W30 is at 8%.

https://sharena21.springcm.com/Publ...bd3/3aa410a1-0bbd-e711-9c12-ac162d889bd1

If you are willing to spend a little more or happen to find it on sale, the Modern Engine 5W30 is down at 8.2% Noack loss.

Amsoil SS 5W30 is at 6.7% Noack loss, while the 10W30 flavor is way down at 4.1%...these are higher SA oils, though, and normally more expensive than even VME.

I decided to try Ravenol DXG 5W30 once and was shipped dexos1 product instead of dexos1 Gen 2. I was able to return it at no cost to me, but that made me that much more fond of just buying oil at WM.
 
Sounds good VP.

----------------------
Buster
I really like AP oils. I'm nervous about running Mobil-1 AP 0W20 in my 2.4 GDI Hyundai. Manual viscosities start at 5w20 and I'm aware there's virtually no differences between zero and five, unless it's well-well below zero outside.

But the South Koreans decide the cut-off line and not me, during my 10 year warranty-time. So I'm nervous about showing the dealer 0W20 Walmart receipts someday, if needed. Not knowing the Ultra Platinum numbers that SOPUS hides - but knowing that oil cleans the engine like the Dickens, I'm using the 5w30 currently.
 
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The oil leaving the crankcase through the PCV system is full oil that contains additives and contaminants. It's oil vapor that doesn't have additives.

Valvoline Modern Engine claims to use a unique detergent that helps clean the IVD's.
 
Originally Posted by circuitsmith

It's been theorized that IVD is caused by combustion gasses traveling from the combustion chamber past the intake valves at the beginning of the intake stroke.
That's how engines with variable valve timing eliminate the separate EGR system.

How then do exhaust valves manage to stay relatively clean and why wouldn't the engine builder just slightly modify the IV lift profile to address this in CVVC's..if it were just that???

Anywho.. for the engine builder my guess is noack% is a bigger concern (than ivd reduction) in meeting CAFE, emissions reqs and emissions systems longevity. And I don't suppose the thin lubes used in today's GDI engines helps in preventing oil from getting past stem seals either. What's the manifold vacuum like on a tgdi..is it greater than a N/A PI engine?? You combine all these things with the fact that the valves aren't getting washed by fuel and you got yourself a potential IVD problem.
 
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Originally Posted by circuitsmith
Are PCV fumes entirely responsible for IVDs?

No, but the PCV oil mist (liquid-oil droplets) is responsible for most of the IVD.

I can't post the whole Afton paper because of copyright issues, but I'll repeat its summary here.

----------------------------------------------------

Afton/SAE paper on IVD

Formation of intake-valve deposits in gasoline direct-injection engines
Gregory Guinther and Scott Smith -- Afton Chemical Corporation
October 17, 2016

https://saemobilus.sae.org/content/2016-01-2252


I will put their conclusions here. IVD means intake-valve deposits.

SUMMARY/CONCLUSIONS

* A standardized, vehicle-based GDI IVD test has been developed that is both repeatable and responsive to known additive chemistry.

* Higher engine loads lead to an increased rate of deposit formation.

* IVD formation in this protocol is an oil-related process, and the majority of the oil that finds its way onto the intake valves comes from the PCV system.

* The oil leaving the crankcase through the PCV system is whole oil containing additives and contaminants (not distilled base oil vapor which contains no additives).


* PCV gas flow in the intake manifold is inconsistently distributed among the eight runners of the manifold leading to the valves.

* Inhibiting the carbon-formation process lessens the rate of deposit formation on the intake valves.

* Oil consumption past the rings bring both additive and nonadditive elements into the combustion chamber where they are incorporated into the exhaust-gas particles.

* Particles found in EGR exacerbate deposit formation rate.

* Particles found in EGR appear to incorporate combusted oil additive components, engine wear metals, and ambient air contamination.

Gregory Guinther and Scott Smith
Afton Chemical Corporation


Note the conclusions I highlighted. They are saying that the main source of the intake-valve deposits is PCV. However, it's liquid oil (whole oil) coming through PCV as a mist, not evaporated oil (oil vapor). So, the amount of oil coming through PCV has nothing to do with the Noack volatility.
 
Originally Posted by Mad_Hatter
How then do exhaust valves manage to stay relatively clean and why wouldn't the engine builder just slightly modify the IV lift profile to address this in CVVC's..if it were just that???

Honda CVCC is the best.

[Linked Image from thetruthaboutcars.com]
 
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