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Saw a demo today by a company seeking to market their motor oil.    It appeared impressive but I wonder what real-world relevance it has.  Any tribologist experts in the Faculty of Sideways?

The demo used an electric motor to spin an axle with a disposable collar in an oil bath, and pressed a roller bearing to it, so that the roller could not spin.     The pressure was increased until the roller to collar seized.    The pressure was by hand with a beam, like a beam-type torque wrench, and an ammeter dsiplayed the load on the motor.

First, an 'ordinary' motor oil was used, said to be Mobil 1.     After it seized, the roller bearing was shown to have significant wear, a dimple on its surface.

Then the oil bath, collar and roller were washed with brake cleaner, and the bath refilled with the special oil.  The roller to collar point of contact was adjusted to provide a fresh surface.   The test was repeated, but with no seizure, right up to the pressure that caused it before.    Moreoever, when inspected, there was no wear of the roller, only a tiny area that was polished.

This was claimed to be due to additives in the oil, which were admitted to includeover 1000ppm of ZDDP, but also other un-revealed agents.

 

Now, I think this test is way beyond any normal wear process in an engine, in which the oil prevents contact between the surfaces of a bearing by hydrodynamic lubrication.   It shows boundary lubrication, in which the surfaces touch, heat up and wear by friction.     This should never happen in a well-running engine (except a Triumph on start-up, when the OE filter has allowed all the oil to fall back into the sump!).  The company claim increased power, and reduced fuel consumption due to better lubrication, so that their product works in the normally working engine.   

So is it as impressive a test as it appears?  

JOhn

Edited by JohnD

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Hi John

Sorry  I wasn't suggesting that they needed to be read, although a quick Google will turn up a number of descriptions "free" of the main engine oil ASTM tests, what I was implying (badly) was that an oil company doesn't have to come up with a gimiky test to show how good their oil is, just publish the full ASTM test data and the results will show exactly where on the continuum from Super Oil to Snake Oil a particular oil is.

Alan

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I'm sorry, Alan!   Grumpy response, partly due to being tired but also to being 'on the phone'.     Lng replaies not easy for me on the mobile!

I should have thanked you for an answer I would have been proud to produce for myself, pointing to the approved and established tests - which I shall now look for!

And ffind!  First, this video uses exactly the same setup, just different kit, to 'test' an oil: 

 

 

Then, a page and video of the SRV ( "Schwingung, Reibung und Verschleiss"!) test rig that does the approved ASTM and DIN test.

https://www.crodalubricants.com/en-gb/discovery-zone/how-we-test-our-products/schwingung-reibung-verschleib-srv

Thnaks again!  I can show my course colleagues, who were similarly impressed and almost as sceptical, why they were right!

John

Edited by JohnD

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Indeed, it is always easy to come up with a testthat suits your product, be it a magic window cleaning thingy at a bank holiday market, or something to prove the oil is wonderful. And remember all those shiny Mini bonnets used to demo Mer polish?

I wonder if it has high levels of PTFE or suchlike. Slick 50 springs to mind....

Better test. Chuck the oil in a RBRR car, and then test it after the run when hot. See how it does then!

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Hi,

This makes an interesting read if you have a few hours to spare:

https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/

I don't think I have linked it here before?

I did post the link on the TSSC forum, but it was too much for them as unless it's 20W50, high in ZDDP & is less than a page long; its kak.

I use #6 on the list. Apart from a leak on front crankcase seal, no problems. I run the same in modern, so always have some available.

Cheers,

Iain.

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13 hours ago, spitfire6 said:

Hi,

This makes an interesting read if you have a few hours to spare:

 

Hm see what you mean about needing a few hours, will admit to expending an hour so far, but book marked for further reading.

I can see why a lot of classic petrol heads wouldn't like what he has to say about long held beliefs!

On the whole to me the guy writes sense (even though he could do with being taught to precis) and the test methodology good, also confirmed to me that my anal attention to oil temp for the competition car wasn't a waste of time and effort.

Surprised to find that my English oil choice Millers Syn Nano Tech had got into his testing and just fell into the Incredibly Good band.

Alan

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Haven't read it fully. Find him an arrogant bastard tbh and suspect I would not like to have a beer with him. An usually strong reaction for me!

However, this is not to discount his very considerable work and I shall read it properly when time and energy permits.

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3 hours ago, Nick Jones said:

Haven't read it fully. Find him an arrogant bastard tbh and suspect I would not like to have a beer with him. An usually strong reaction for me!

 

Funny but almost exactly my train of thought when reading. If some of the content hadn't chimed as good, I'd have given up reading very quickly.

If he got someone to precis it for him, it could be  a good reference, at the moment its rather like Castor Oil, you know it may help but swallowing it is very unpleasant.  

Alan

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Hi,

 Its contents and belief in a fair amount of it, caused me to get a friendly warning from an admin.

It is a good read. He does repeat the same stuff a lot & when asked to review the document with a view to "cleaning it up"; He replied that he has no time & its free. Fair point. I have had to google precis..

 The contact breaker points paragraphs are only valid IMHO if comparing to transistor assisted systems.

Cheers,

Iain.

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Hi,

 In my quest to find the super oil I found this excellent read for a rainy day:

https://members.rennlist.com/oil/Motor Oil 101.htm

20W50 will never touch my engine.

A couple of questions please regarding Triumph 6 cylinder CP/R engine please:

  1. Oil pressure relief valve does not flow as good as it should?
  2. Oil bleed from PRV is returned back to pump inlet?
  3. Galley to oil PRV has no connection for pressure gauge?
  4. Oil pressure gauge/switch is a post filter connection?
  5. Max oil pressure reading is PRV pressure plus filter differential pressure?

Thanks,

Iain.

 

 

 

 

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1. Oil pressure relief valve does not have sufficient capacity to provide full relief (i.e. Maintain a constant pressure). However , this is probably intentional to provide higher oil pressure at higher rpm.

2. Yes PRV overspill returns to the pump inlet on the 6 (but back to dump on 4 pots IIRC.

3. There is a big gallery plug (3/8" bspt) next to the PRV that could serve with a suitable adapter - not sure it would show anything useful though.

4. The usual gauge tapping below the distributor is into the main oil gallery, post filter.

5. I suppose the pre-filter pressure will be a bit higher than post filter pressure an the proportional difference will increase with rpm due to greater flow causing more losses. Probably not by much though. Filters gradually clogging use would also show up. Filters should have an internal relief valve to bypass the element should the differential across it become excessive.

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