NOACK vs TEOST

[wpod]

Engine oils are blend of base oils and additives added to meet a finished product rating which over the last 30 years have become increasingly severe. We choose a name brand oil from one of the major oil companies / blenders and hope the company reputation will provide an adequate product. We seem to have engines last a very long time with proper maintenance and a bit of luck with out the need of a boutique brand.

 

[Jetronic]

We are looking at a 40-year-old iffy, obscure paper here. Since when POE causes engine deposits? Who knows what went wrong in that paper. They didn't use the proper antioxidant? They used a very unstable POE? More importantly who cares?

Tom NJ is right on that there are many oil-deposit tests and they may or may not correlate with actual engine deposits. TEOST 33C was recently shown not to correlate with turbocharger deposits at all.

GM turbocharger test: No correlation for deposits with TEOST 33C or moly

It turns out that TEOST 33C test is useless for judging turbocharger protection. Antioxidant is the key, along with the VII (or the lack of it) and dispersant. Moly has no effect. However, I think TEOST 33C may be better correlated with intake-valve deposits (IVD) in turbo gasoline...

www.bobistheoilguy.com

Regarding moly it's interesting that moly is not what causes the deposits in TEOST 33C but it serves as a catalyst to form deposits. This is why SAE 0W-16 and SAE 0W-20 are exempt from TEOST 33C in ILSAC, as Japanese OEM's like to load them with high moly content, such as 600 ppm Mo or above, and such high-moly oils would fail TEOST 33C, despite performing very cleanly in an actual engine.

TEOST MHT is no longer used as far as I know.

Both TEOST 33C and TEOST MHT use a catalyst (a different type in each) to induce deposit formation. This is probably why it is so hard to correlate them with actual engine deposits. They may be more useful for screening purposes when designing oil blends.

buster is right that the additives, detergents, dispersants, and VII also play a major role.

There is some truth to some extent that higher Noack reduces deposits as the oil evaporates faster before it can deposit. Thinner oils also have lower aniline points and better solvency. However, if higher Noack also means inferior base-oil quality, this could increase the deposits.

As for the polybutylene, it does evaporate extremely cleanly, without leaving deposits. However, it looks like it's only available in very high viscosities, such as KV100 ~ 20 cSt; therefore, you would only see it in some monograde etc. applications. It is used as a replacement for bright stocks—high-viscosity Group I base stocks, as these are becoming less and less available as solvent-refining to make Group I base oil is being abandoned.

Coming back to POE, Valvoline Premium Blue Restore is specifically designed as a maintenance oil to clean the carbon deposits around the piston rings in one oil-change interval. Its base oil has 62.5% POE.

Here is the Valvoline Premium Blue Restore formulation.

Formula #4 is what is sold commercially.

Priolube™ 1973: an 8.00 cSt POE by Croda
Synesstic™ 12: a 12.4 cSt AN by ExxonMobil
D3495L: a detergent–dispersant–inhibitor (DDI) package by Infineum
PX-3871: a mixed alkyl borate ester additive for dispersancy, antiwear, and friction modification (antifriction) by Dorf Ketal

It's unlike any other oil. Valvoline Premium Blue Restore has:

Base-oil composition: 62.5% (50/(50+10+15+5)) POE (ester), 25.0% ((15+5)/(50+10+15+5)) PAO, and 12.5% (10/(50+10+15+5)) AN (alkylated naphthalene)
No viscosity-index improver (VII) at all—a monograde oil
Standard Valvoline Premium Blue Synthetic HDEO additive package (20% of the finished oil)

Therefore, unlike what that old paper reported, POE, with its extremely high solvency and extremely low aniline point, does a better deposit-cleaning job than any other base oil.

Euro Mobil 1 oils (FS and ESP varieties) also use POE for better cleaning of diesel engines as well as meeting the severely extended Euro oil-drain intervals.

So this is like a Redline by Valvoline oil?

 

[Tom NJ]

Blingo, you are correct that different conditions exist in different parts of an engine, and that lubricants can perform differently throughout the engine. POEs have a very low Noack volatility, generally half that of an equivalent viscosity PAO. Therefore a POE may spend a significantly longer time pooled on a static hot surface, and under some conditions may oxidize to a varnish before it can volatize off. The solution is often a more volatile POE, or one with a more oxidatively stable structure. In a dynamic flow environment, the solvency characteristics of polar POEs help reduce deposits due to their washing effect.

There are literally scores of different POEs used in lubrication and their properties and performance characteristics vary according to their chemical structure. Some POEs have less oxidative stability than a Group I mineral oil, and others can cleanly lubricate a jet engine for 25,000 hours. As with all lubricant components, selecting the right ester for the application environment is important to the total performance. There are no perfect universal base oils, which is why formulators usually blend various chemistries to achieve the desired results. Fortunately POEs are very versatile and their structure can be tailored to the environment they will operate in, something I spent much of my career doing.

By varying the structure of esters one can affect and manage such properties as oxidative stability, thermal stability, hydrolytic stability, coking tendencies, lubricity, viscosity, volatility, viscosity index, low temperature flow, biodegradability, seal compatibility, and cost. Compared to PAOs for example, if you seek a base oil with a KV100 of 6 cSt you have basically two PAO choices - a straight cut 6 cSt or a blend of say a 4 cSt and an 8 cSt. In either case the properties and performance are very similar. With esters one can choose from dozens of 6 cSt products, each with different structures and properties, customized for the application.

And we must never forget the extremely important role of additives. Comparing pure base oils without taking additives into account can be rather misleading. Esters as a family are able to solubilize much higher additive levels than PAOs, which adds to their versatility. While most PAO based lubricants that I have seen generally have less than 1% anti-oxidants, I typically used 2-3% anti-oxidants in my ester based formulations. This can make a big difference in oil life and cleanliness. The combined effect of an enhanced stability POE with higher anti-oxidant levels sets this chemistry apart in many high temperature applications, jet engines being a classic example.

 

[Gene K]

So this is like a Redline by Valvoline oil?

My understanding is the POE in Restore was specifically chosen for it's cleaning properties. I suspect it is not the same specific POE used by Redline which likely had different priorities in lubricant formulation.

 

[Tom NJ]

My understanding is that the POE used in Restore is a Neopentylglycol Diisostearate (NPG iC18) which is much less polar than the POEs typically used in PCMOs or jet engine oils. It also has a very high VI and excellent lubricity. They likely chose it because of its milder affect on seals, and they use a higher dose for cleaning. Smart choice, and would be mine for a PCMO formulation.

 

[Gokhan]

My understanding is that the POE used in Restore is a Neopentylglycol Diisostearate (NPG iC18) which is much less polar than the POEs typically used in PCMOs or jet engine oils. It also has a very high VI and excellent lubricity. They likely chose it because of its milder affect on seals, and they use a higher dose for cleaning. Smart choice, and would be mine for a PCMO formulation.

Croda Priolube 1973 datasheet

 

[Gokhan]

Blingo, you are correct that different conditions exist in different parts of an engine, and that lubricants can perform differently throughout the engine. POEs have a very low Noack volatility, generally half that of an equivalent viscosity PAO. Therefore a POE may spend a significantly longer time pooled on a static hot surface, and under some conditions may oxidize to a varnish before it can volatize off. The solution is often a more volatile POE, or one with a more oxidatively stable structure. In a dynamic flow environment, the solvency characteristics of polar POEs help reduce deposits due to their washing effect.

There are literally scores of different POEs used in lubrication and their properties and performance characteristics vary according to their chemical structure. Some POEs have less oxidative stability than a Group I mineral oil, and others can cleanly lubricate a jet engine for 25,000 hours. As with all lubricant components, selecting the right ester for the application environment is important to the total performance. There are no perfect universal base oils, which is why formulators usually blend various chemistries to achieve the desired results. Fortunately POEs are very versatile and their structure can be tailored to the environment they will operate in, something I spent much of my career doing.

By varying the structure of esters one can affect and manage such properties as oxidative stability, thermal stability, hydrolytic stability, coking tendencies, lubricity, viscosity, volatility, viscosity index, low temperature flow, biodegradability, seal compatibility, and cost. Compared to PAOs for example, if you seek a base oil with a KV100 of 6 cSt you have basically two PAO choices - a straight cut 6 cSt or a blend of say a 4 cSt and an 8 cSt. In either case the properties and performance are very similar. With esters one can choose from dozens of 6 cSt products, each with different structures and properties, customized for the application.

And we must never forget the extremely important role of additives. Comparing pure base oils without taking additives into account can be rather misleading. Esters as a family are able to solubilize much higher additive levels than PAOs, which adds to their versatility. While most PAO based lubricants that I have seen generally have less than 1% anti-oxidants, I typically used 2-3% anti-oxidants in my ester based formulations. This can make a big difference in oil life and cleanliness. The combined effect of an enhanced stability POE with higher anti-oxidant levels sets this chemistry apart in many high temperature applications, jet engines being a classic example.

blingo has a rotary Mazda engine and is worried about synthetics causing more deposits.

The problem is that the lubricant is more than the base oil as you said, and he will never know because the additives play a huge role.

Besides, how do you choose a base oil and/or an additive package? You are stuck with whatever they put in the bottle, and often you don't know what is inside and even if you do, you don't know how they synergize.

blingo perhaps needs to move this discussion to a thread about rotary engines such as the following. Amsoil, ACEA (FS and ESP) Mobil 1, etc. clean very well with their PAO & POE content and API/ILSAC Mobil 1 cleans well with its PAO & AN content, but what they do in a rotary engine is beyond what was originally intended to be discussed in this thread. My take is that any excellent synthetic oil will also perform well in a rotary engine. Last but not least, conventional oil is no longer available in developed countries, such as the US or blingo's country Germany, as I wouldn't refer to hydroprocessed (hydrogenated) Group II base oil as conventional, which is really no different than identically hydroprocessed Group III base oil sold as synthetic. Good luck finding a dino Group I solvent-refined mineral oil these days unless you go to a developing country, where these oils, commonly available as 15W-40, 20W-40, 20W-50, 25W-40, etc., are still the most popular oils due to their low cost.

Oil for Rotary Engine

So, I have been trying to decide on which oil I want to run in my Rx7 most all of the time. 10w40 of whatever flavor is on sale has been doing fine. I landed some Mobil 15w50 and PP Euro in the autozone sale and am going to try those when the time comes. My question is rotaries are designed to...

www.bobistheoilguy.com

 

[blingo]

As if I was some mineral ultra... Fortunately MolaKule recently got so annoyed by me that he had me explain my phantasies timely as a second funny twist now. Much more compact than your reality – and even so the preferably lower polarity somehow got in it by then:

"My idea why the POE did so exceptionally bad according to the ancient Idemitsu fragment became suspecting the combination of their high polarity and high thermal stability. While among the properties of the non polar PIB an early and especially clean decomposition seemed to be advantageous.
So PIB (for cleanliness and maybe good EHL regarding the side gears in a rotary) + GTL (for high VI) + BT4 or else for even higher VI, good lubricity and medium to low polarity is what I'd be shopping for by now. If I had any chance."

OSP and AN I'd forgotten, as the Estolides alone would probably suffice. Anyway, before that there had been the interesting first twist, this workaround of intentionally higher NOACK volatility for tailored POEs. And Gene K could hardly say he'd never wanted to know all of it

I beg your pardon though now, Gene, and thank you a lot for your patience, Tom.

Without meaning to impose the thought and critique I still became so oppressant. That's unnecessary of course. I'm in no hurry – killed my engine from just experimenting with non standard spark plugs and if necessary will just kill again. Good night, gentlemen.

 

[Gene K]

As if I was some mineral ultra... Fortunately MolaKule recently got so annoyed by me that he had me explain my phantasies timely as a second funny twist now. Much more compact than your reality – and even so the preferably lower polarity somehow got in it by then:

"My idea why the POE did so exceptionally bad according to the ancient Idemitsu fragment became suspecting the combination of their high polarity and high thermal stability. While among the properties of the non polar PIB an early and especially clean decomposition seemed to be advantageous.
So PIB (for cleanliness and maybe good EHL regarding the side gears in a rotary) + GTL (for high VI) + BT4 or else for even higher VI, good lubricity and medium to low polarity is what I'd be shopping for by now. If I had any chance."

OSP and AN I'd forgotten, as the Estolides alone would probably suffice. Anyway, before that there had been the interesting first twist, this workaround of intentionally higher NOACK volatility for tailored POEs. And Gene K could hardly say he'd never wanted to know all of it

I beg your pardon though now, Gene, and thank you a lot for your patience, Tom.

Without meaning to impose the thought and critique I still became so oppressant. That's unnecessary of course. I'm in no hurry – killed my engine from just experimenting with non standard spark plugs and if necessary will just kill again. Good night, gentlemen.

No problem. This is the kind of thread I would like to see more of. Some of its over my head but a little bit sticks every time guys get serious about the details.

Doesn't Castrol make a special oil just for Rotaries?

 

[Gene K]

Engine oils are blend of base oils and additives added to meet a finished product rating which over the last 30 years have become increasingly severe. We choose a name brand oil from one of the major oil companies / blenders and hope the company reputation will provide an adequate product. We seem to have engines last a very long time with proper maintenance and a bit of luck with out the need of a boutique brand.

Has worked for me with Delo, Delvac and Rotella. Haven't had an oil related issue yet. Since they all meet HDEO OEM Guidelines for +50% drains I have to assume they are built to more than minimum API spec. Although many other oils do as well.

 

[wpod]

Gene have you retired or still have the big truck?

 

[Gokhan]

As if I was some mineral ultra... Fortunately MolaKule recently got so annoyed by me that he had me explain my phantasies timely as a second funny twist now. Much more compact than your reality – and even so the preferably lower polarity somehow got in it by then:

"My idea why the POE did so exceptionally bad according to the ancient Idemitsu fragment became suspecting the combination of their high polarity and high thermal stability. While among the properties of the non polar PIB an early and especially clean decomposition seemed to be advantageous.
So PIB (for cleanliness and maybe good EHL regarding the side gears in a rotary) + GTL (for high VI) + BT4 or else for even higher VI, good lubricity and medium to low polarity is what I'd be shopping for by now. If I had any chance."

OSP and AN I'd forgotten, as the Estolides alone would probably suffice. Anyway, before that there had been the interesting first twist, this workaround of intentionally higher NOACK volatility for tailored POEs. And Gene K could hardly say he'd never wanted to know all of it

I beg your pardon though now, Gene, and thank you a lot for your patience, Tom.

Without meaning to impose the thought and critique I still became so oppressant. That's unnecessary of course. I'm in no hurry – killed my engine from just experimenting with non standard spark plugs and if necessary will just kill again. Good night, gentlemen.

These are your "phantasies" indeed, and @MolaKule is right on for calling you on them.

You seem to be using Google Translate from German to English, which often makes it painfully difficult to understand what you're trying to convey.

Here is the full text of the Idemitsu Kosan Co. Ltd. paper from October 19–22, 1992.

The development of lubricating oils for rotary engines
Takao Yabe, Toshihiko Arai, Shoji Aoyama, and Masayuki Oshima
Idemitsu Kosan Co. Ltd.
International Fuels and Lubricants Meeting and Exposition
October 19–22, 1992

The main problem I see with this paper is that it's not stated if the authors used an antioxidant in their oil formulation. Mineral oil (API Group I) serves as its own antioxidant because of the aromatic compounds in it. However, a synthetic oil would oxidize and leave deposits very quickly without an antioxidant. Therefore, it is more than likely that the conclusions of the entire paper are invalid.

One of the main limitations for polybutene seems to be the low flash point, which is around 130 °C or less. It probably has other limitations as well, such as very high Noack. The low flash point may perhaps help in a rotary engine, which requires burning oil, but it would be problematic otherwise.

Kemat low-molecular-weight conventional polybutene

Stick with a top-quality brand-name oil. One more time: It is the sum of the ingredients (synergy between the ingredients) that matters most—not the individual ingredients.

 

[blingo]

Your occupation's getting really absurd. The additivation, well: Only hours before you first tried that number from your mansplaining revue I had answered someone's PM by ending with a line that finally read "... GDI intakes might like some ester content of some sorts, but might be just as fine from additivation, as for detergency et al. there'd be more than one strategy."
How I started this answer? With "Hello" and "... I can impossibly be of any help,..."
Still, that I'm aware of antioxidants you cannot forget, I bet.

That's the copy I have, two pages missing unfortunately. Didn't order the article from the SAE to perhaps get it all. The rotary aint hard on the sump oil, already did 31000 km before UOA to get a feeling if I can discard oil changes with my car. The normal continuous exchange rate thanks to the metering oil pump may be sufficient with today's oils...
What they did were TFC tests for base oils, TFC for "fully formulated" oils, then "in-house" engine testing with those and then win Le Mans. But they splitted the task. Additivation not of too much importance as in my short excerpt they were after the "engine oil" to end up burnt in the chamber. Their "system oil" went into the sump.
PIB and PAO were easily discriminated from POE, what about their oxidation? Not exactly API Grp. I either, therefore quite probably a fundamental difference, taking other findings into account. But it's true, they just went another route instead of tailoring for le Mans of that year. That's how the additional links to independent findings appeared here. Initially to show TEOST MHT limitations, but it all could still be read above.

Including passivation and general magic already mentioned in #22. You need not show that much interest in anything. Really unnecessary. Of course we could begin endless speculating, what if. What if this toxic TCP from your excerpt, that ain't to be had in the Aeroshell 15W-50 these days, had been passivating internals then or would do now. And so on. But it wasn't the right place at all, remember?

#21 was for answering someone else's question about the PB. I answered for the thin end and for the area of my interest somewhere between no VI and much tackiness, finally for thick and very thick end. Did my own search on the materials, had even heard of thick mineral grades before, had read Rudnick's chapters from the second edition and the ester chapter from the third edition, which is also available somewhere, searched the polymeric esters and more, am looking into decomposition comics to this day.
Still have seen general relevancy right into the modern diesel realm not only from that old Cummins / NASA graphic novel or oven chain bibles.

As bad as my writing is, it's too late to edit anything now. You definitely should start all over if you wanted to consider correcting a sentence or two. Then maybe start us a dedicated thread. I'll be right there, just leave a door open, if you please. Decide, what you want to do, and go for it when you're ready to go.
For my part I shall leave from this thread.

 

[Gene K]

Gene have you retired or still have the big truck?

Small Fleet Operator now. Still get my feet wet on occasion.

 

[Gokhan]

Here is the full text of the Idemitsu Kosan Co. Ltd. paper from October 19–22, 1992.

The development of lubricating oils for rotary engines
Takao Yabe, Toshihiko Arai, Shoji Aoyama, and Masayuki Oshima
Idemitsu Kosan Co. Ltd.
International Fuels and Lubricants Meeting and Exposition
October 19–22, 1992

The main problem I see with this paper is that it's not stated if the authors used an antioxidant in their oil formulation. Mineral oil (API Group I) serves as its own antioxidant because of the aromatic compounds in it. However, a synthetic oil would oxidize and leave deposits very quickly without an antioxidant. Therefore, it is more than likely that the conclusions of the entire paper are invalid.

One of the main limitations for polybutene seems to be the low flash point, which is around 130 °C or less. It probably has other limitations as well, such as very high Noack. The low flash point may perhaps help in a rotary engine, which requires burning oil, but it would be problematic otherwise.

Kemat low-molecular-weight conventional polybutene

Stick with a top-quality brand-name oil. One more time: It is the sum of the ingredients (synergy between the ingredients) that matters most—not the individual ingredients.

I was too harsh on the authors.

This is a conference paper, where the authors went to give a talk.

Their goal was to find an oil that eliminated spitback during endurance race caused by deposits on the three apex seals of the triangular rotors (like deposits on piston rings), and they met this goal by blending an oil using polybutene, which won the race. The paper really made no other claims. The paper is a good paper within its scope.

Now, to use the intermediate findings of the paper or generalize its conclusion to reach general conclusions for general applications on base oils, particularly esters, which are a huge class, polybutene, engine deposits and bench deposit tests, which rely on many factors, etc. is a big stretch to say the least. It is a common fallacy to interpret findings beyond their scope or generalize them.

There is probably no need to be obsessed so much with oil for a Wankel rotary engine that is already damaged and broken due to improper maintenance—a damaged and broken engine notorious for very poor reliability, very poor fuel efficiency, and very high emissions even when it's brand-new—unless you are running a Rotary Club (pun intended).

 

[blingo]

Will you never learn to read what's actually written down, deal with it so that you allow yourself to arrive at any other reactions than siffy essays of eliminatory motivation?

Mélange, 20000 miles, rotary Mazda RX-8 w. 90000 miles

This I had analysed to get a feeling if I would discard oil changes with the car, not for judging performance of an individual oil obviously. (Ro 80 rotaries in the end were said to not require them any longer it seems and although the Renesis' continuous exchange rate should be about half as...

www.bobistheoilguy.com

Everyday mpg around 23 with me, emissions level is Euro-4 as with any car of it's time.
I don't love my car. If I rebuild or replace the engine I'll more or less do it for then "testing" oil or weird cocktails in it.

New oil additive saves 2% on gas

When are we going to start a reunion forum so the old reincarnated trolls can all be welcomed properly?

www.bobistheoilguy.com

Go back to page one and try again. Tom mostly shows the way. All the thread's excursion actually was about relating tests to in-use deposition, critique. Hardly anyone but you ever managed to get almost everything passively and actively wrong. As far as it had content beyond enlightenment about developing economies' mineral viscosities at all. Or similar condensates from last nights' dreams about my person or else.

In in-house high temperature, thin film deposit tests that my former company ran regularly, PAO and Group III based oils always left more deposits than Group I or ester based oils. The lack of polarity/solubility of these higher group hydrocarbon base stocks meant they were not able to solubilize or disperse oxidation by-products that lead to deposits. Pure ester based oils were always the cleanest by far, and had the lowest Noacks by far.

That said, our test oils were industrial and aviation products that did not contain detergents or dispersants, which can influence such tests, and we never attempted to establish any correlation between our test and the TEOST test. The solubility principle, however, may still apply.

Certainly all valid. Just not explaining everything anywhere. Tom went on from there. You never did. You just arrived at picking Grp. I from a handful of base oils now and thought it would let you eliminate what you don't like. Maybe time for you to once more spell a word like scientific or so. It's still getting lost what you actually contribute regarding the problem ;-)

Need a hint to find your way to topic, an entrance maybe? There'd be one next complication like that: One article on PIB once had a caveat that you could have PIB actually causing deposition on a piston crown or so. I think it was about blending different grades of it. Much tackiness from getting that wrong was said to be causing deposition. Could look it up if you'd develop some interest in anything. But...
Tackiness? Maybe just explain this next complication in context to all. Tackiness, Polarity, NOACK – Private Saving POE would make for fine bait, wouldn't it? Subheader: ...and how the NASA got in

Either way, thanks a lot for helping me with the maintenance for the rotary...

 

[Gokhan]

As I said before, it feels like you are communicating over Google Translate between German and English, and you're struggling to understand our posts, and most of the time, we have no idea what you are trying to say.

You seem to have minimal formal scientific background. This Google-scientist thing you are doing is only resulting in colorful phantasies, not actual science. People don't need your interpretation of TEOST, POE, PIB, etc.—they can hit the search button on Google themselves and get a much more objective, undistorted version of the facts.

 

[Tom NJ]

Now now, boys - friendly site, play nice!

 

[blingo]

But he's right, I do like the search engine. Somewhere out there must be people putting up things for others searching on "clean decomposition" etc. pp.... The Lube-Tech says so. From 2.2.3

http://www.lube-media.com/wp-content/uploads/2017/11/Lube-Tech102-Newinsightintothebenefitsofsyntheticestersinchallenginglubricantingapplications.pdf

To each his own cleanliness, right? This whole oven chain milieu is growing on me.

In addition the new board here broke my "mélange" and some formatting in the older entries. Something like that is always enough to just go on and on highlighting another one's background. Gokhan, what you have is your need to drive me out or at least see this thread shut down. That's sad but not that serious, right again?

 

[Gokhan]

But he's right, I do like the search engine. Somewhere out there must be people putting up things for others searching on "clean decomposition" etc. pp.... The Lube-Tech says so. From 2.2.3

http://www.lube-media.com/wp-content/uploads/2017/11/Lube-Tech102-Newinsightintothebenefitsofsyntheticestersinchallenginglubricantingapplications.pdf

To each his own cleanliness, right? This whole oven chain milieu is growing on me.

In addition the new board here broke my "mélange" and some formatting in the older entries. Something like that is always enough to just go on and on highlighting another one's background. Gokhan, what you have is your need to drive me out or at least see this thread shut down. That's sad but not that serious, right again?

Nothing. Good luck with your mélange.