UOA's and Engine Wear (again)

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A member suggested I start a new thread with this quote I found on Corvetteforum.

Nothing we haven't heard before. Notice in the video they talk about electron microscopes look at engine wear in 3D.

Quote:
As an ex oil and product tester (outboard oils, Mobil 1 products) , I can tell you that the typical UOA done by Blackstone, Dyson, Avlabs and the others, don't often contain valid wear rate data. It's useful for trend only, same lab, same oil, same engine.

For example, the iron numbers are in PPM (parts per million) . If, you were to measure the size and weight of the particulates, you might, might have some wear based data. However, that's a rare and expensive set of tests. Even then, there are far too many variables.

Stop and consider just how much wear it takes to produce 50PPM, for example (it's tiny). And, do those 50 particulates remain suspended? Or do some of them remain elsewhere? Like in the sludge of a conventional oil, infrequently changed? Or, in the case of certain engine designs, lodged in drilled passages in the crankshaft, through centripetal force.

A far more valid set of wear related testing protocols are involved. Including actual part measurements with scanning electron microscopes. Both destructive and non destructive.

I don't claim to be an expert. I will claim to have seen the experts at work, and it's mighty impressive.

UOA is a tool, and not anywhere near sufficient to determine wear rates, especially between brands, users, and engine types.
 
I agree, right down to the labs he mentions.
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It's a tool which might be helpful to detect a coolant leak, a bad injector, or if you can stretch the OCI a bit, that's about it.
 
Originally Posted By: demarpaint
I agree, right down to the labs he mentions.
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It's a tool which might be helpful to detect a coolant leak, a bad injector, or if you can stretch the OCI a bit, that's about it.


+1. I have done two UOAs about three years ago out of curiosity. The only way I would do one now is if I started slowly loseing coolant to see if it was going into the engine. As you said a faulty injector could cause fuel delution of the oil. As I do only 10K OCIs I see no worth while reason for a UOA.
 
Quote:
do those 50 particulates remain suspended? Or do some of them remain elsewhere? Like in the sludge of a conventional oil, infrequently changed?

That has been my contention right along when folks want to see a UOA of an engine being cleaned with an additive.

Any particulates that are in the deposits will be released into the oil and show up in the UOA.
The only thing i look for is coolant and fuel and maybe excessive lead if there is a reason to be looking otherwise spend the money on a oil change.
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It's also possible that when an oil cleans, you'll see a spike in oil consumption for several thousand miles. Possibly due to cleaning up the rings....
 
Originally Posted By: INDYMAC
So what is the purpose of this thread? Why is there a Mobil 1 commercial? Interesting...

I was the one who suggested he post the quote because it provides the opinion of someone who is involved in engine testing and who works with people who analyze wear.
 
I also agree.
A UOA is all about the oils condition not wear numbers.

I've said this before but I'll say it again, you'd be much better off putting the cost of regular UOA towards the one time installation cost of an oil pressure guage. With the possible exception of TBN it actually provides more info' and in real time.
 
I posted some of the above on the corvette forums. I worked for Mobil many years ago. I never worked in passenger car oil testing. I was involved in a very minor way, in mobil 1 synthetic aviation product testing. Some of which was branded M1 some was simply av spec synthetic. I was a tech, not an engineer. Those engineer guys are light years ahead in oil knowledge. I asked as many questions as I could. So I certainly learned the basics of what they do.

I w
 
Was quite interested in the ability of these guys to determine bearing wear using various different lubricants. Genneraly, it was electron microscope measurements far below any perceptible level.
 
And then there are others on this forum like dnewton3 that thinks he can summarize the OCI for any diesel engines by just looking at a bunch of anecdotal UOAs. There are engineers and then there are internet surfers.
 
I need advice on how to measure and track wear on my 4x4 manual transmission and transfer case. When I changed my transmission fluid, I saved samples of virgin oil for analysis (VOA).

After 1,000 miles, I plan to submit both the VOA sample and the UOA sample to the same lab. Of these analyses below, which should I order to get the best indication of gear wear?

Please note that each of the sample reports above is two pages long. The 2nd page has more wear data so please scroll down to the bottom of the reports. Thanks!
 
I really like both of these formats. Do you have to choose? Can you afford both until you decide to stick with one format over the other?
 
The plan is to save my samples (VOA & UOA) every 1,000 miles until you tell me which lab can give me a good test for transmission wear.

I suggested WearCheck because its elemental reports are more complete and includes sulfur (see links). I don't know the quality of its particle analysis. Thanks!
 
Originally Posted By: INDYMAC
I really like both of these formats. Do you have to choose? Can you afford both until you decide to stick with one format over the other?

Wearcheck sets up an account for you on their web portal. Once you log in, you can access all these reports pertinent to whichever UOA service you requested (MOB2, MOB3, etc.).

You would normally start with MOB2, and only if the results turned up something abnormal, you would then request additional MOB3 test.
 
I already have an account with WearCheck. MOB-3 provides analytical ferrography (ASTM WK15810) for diagnosis of wear causality but does not provide a measurement of wear. It costs an additional $189 over the more common MOB-2 ($24) analysis.

I've collected VOA samples as a baseline. My UOA samples will be collected on the same transmission. The only variable between sampling periods may be the transmission fluid in order to compare the anti-wear performance of different fluids.

For UOA, is MOB-2 sufficient for measuring wear? If not, which ASTM test provides a more credible wear measurement?
 
Originally Posted By: pjf

For UOA, is MOB-2 sufficient for measuring wear?

I'm afraid that none of these $20 UOAs are sufficient for measuring wear. That is not what such tool was designed for. Instead, it should be used as a trending tool and a tool to help determine the condition of the oil and detect if you have any contaminants (fuel, coolant, water).

http://www.bobistheoilguy.com/used-oil-analysis/

As you do your trending, if you see something that sticks out quite a bit, then it sounds like this MOB-3 would help give more info regarding wear.
 
A Blackstone Oil Analysis on my BMW M Coupe was showing Lead and Copper about Ten times the average for this engine (S54). As these powerplants have very fragile Rod Bearings, I had a local shop pull the Oil Pan to find #2 Rod Bearing worn down to pure copper. They said I would have lost the engine at some point in the near future.

Spotted wear for me!

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2496835&page=1
 
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