Which Engine Oil Analysis?

rhkennerly

rhkennerly

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rhkennerly
Which engine oil analysis are you using and why?
Are there any services that are particularly good with the Rotax 912? (Lots of comparative data)
 
I'm using AvLab, simply because when I started they were offering some sort of discount at SNF. What matters most in oil analyses is trend data, so it's probably best to pick one lab and stick with it. I'm not sure there's really much to recommend one lab over another.
 
I can't remember why I started using Blackstone?

Oh maybe because they are close in Fort Wayne?
Doesn't seem to help speed wise. It is up to 3+ weeks now to get a report when it used to be closer to 2 weeks. It could be USPS taking longer to get it there? I use the postage paid ty vac envelopes that the black bottles go into which is new a couple years ago. Many samples made it there pretty fast before the envelope.
 
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Blackstone is one of, if not the, most expensive, but they have some advantages. They have an analyst look at the report and write a narrative instead of just sending the numbers. They will also actually read your notes and respond to them. Both things lacking with other services I've used. They do a lot of aircraft engines, and save the data by tail number, so it will transfer to a new owner when you sell. The owner is a pilot and they have several pilots on staff. I've emailed follow up questions after getting a report, and they reply promptly. Customer service is their niche.

Apparently the owner doesn't have a sense of humor though. He sent @SixPapaCharlie a nastygram over a funny video that didn't even mention them by name. I was disappointed to see that, but I don't know of anyone else that comes close service- wise, so I still use them.
 
Jim K said:
Blackstone is one of, if not the, most expensive, but they have some advantages. They have an analyst look at the report and write a narrative instead of just sending the numbers. They will also actually read your notes and respond to them. Both things lacking with other services I've used. They do a lot of aircraft engines, and save the data by tail number, so it will transfer to a new owner when you sell. The owner is a pilot and they have several pilots on staff. I've emailed follow up questions after getting a report, and they reply promptly. Customer service is their niche.

Apparently the owner doesn't have a sense of humor though. He sent @SixPapaCharlie a nastygram over a funny video that didn't even mention them by name. I was disappointed to see that, but I don't know of anyone else that comes close service- wise, so I still use them.
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Yeah. He's a dick

He knows his stuff but his communications with me were a little dickish
 
I like Blackstone. The analyst comments add value.
 
I've been using LNC Labs mainly because they have information very relevant for the experimental conversion engines which is good for trends. I get numbers and notes with the analysis report.
 
I originally used AvLab until about 18 months ago. Like all of the aviation oil analysis services they provide context for the results in the form of normal level ranges for each item. The problem was that shipping times were way too long. Typically a month from the date I shipped the sample, and too often 5 weeks. It seems that they use a discount shipping mode where the samples were given lower priority by the shipper.

As a result I've switched over to ALS Tribology (https://www.alsglobal.com/en/oil-analysis/aviation-oil-analysis). I ran 3 side by side comparisons and the results were within 5% of AvLab's. Their prices (when I purchased a number of test kits) were about 40% lower than AvLab. And, best of all, I get results in about a week from shipping the samples. Like the others, ALS provides information on normal ranges for each measured item.
 
bkspero said:
It seems that they use a discount shipping mode where the samples were given lower priority by the shipper.
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They had a real fiasco with a FedEx method so they made a change about a year ago. Still FedEx but a different option. Seems better.
 
Oil analysis adds nothing but confusion or confirmation of information you should’ve gotten some other way. I don’t understand how this faith started. It popped up while I was away from flying in the late 90’s. Must’ve been clever marketing or bored journalism.

When has anyone made a major decision based solely on oil analysis? “Just one more tool” is what fans always say, but every tool should have its own use. If oil consumption is stable, performance is nominal, and there’s no metal in the filter, what will you do if OA says “too much [something]?” If oil consumption is increasing, performance is lagging, and the filter is full of metal, what if the OA says “looks great?”

In the first case, OA adds worry but nothing more. “Fly 20 hours and repeat the sample.” What about those 20 hours? Will you fly with your family during that time? IMC? Over mountains or water? And then the repeat sample is “better.” What then? What caused the original anomaly? Is it going to come back? Will you fly family/IMC/mountains? Or maybe the repeat sample is “worse,” but all other parameters are great. What then? Keep worrying, flying, and repeating until the report is acceptable or something else goes bad.

That doesn’t sound like a lot of fun flying. But what it does is it validates OA in the minds of believers; “our oil analysis showed elevated [something], but everything else was ok. We kept a close eye on it and, 200 hours later, the oil filter showed lots of metal. We had it torn down and the cam was badly spalled. So, oil analysis gave us an early indication that something wasn’t right!” This is hogwash.
 
rhkennerly said:
Which engine oil analysis are you using and why?
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Any reputable lab that works with aircraft components will work. Have used many different ones. The key is the consistency in how you obtain your samples to ensure your trend is accurate.


OneCharlieTango said:
When has anyone made a major decision based solely on oil analysis?
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A major decision? No. And all guidance states you shouldn't. Its just one item to use when making any decision concerning the health of your engine.
OneCharlieTango said:
If oil consumption is stable, performance is nominal, and there’s no metal in the filter, what will you do if OA says “too much [something]?
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Simple. Try and find the reason behind the elevated levels. I've already given you examples in other threads of the type of decisions that should be made when an item of concern is noted in a regular oil analysis so I wont repeat them again.
OneCharlieTango said:
So, oil analysis gave us an early indication that something wasn’t right!” This is hogwash.
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FYI: an oil analysis cannot detect all failures. To think otherwise is pure ignorance of how the analysis is used or even its purpose. What I can tell you it has prevented way more catastrophic failures than its missed. Those are the facts.
OneCharlieTango said:
It popped up while I was away from flying in the late 90’s.
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Not quite. Oil analysis has been around much longer than that in the private aviation sector. It simply became more popular as technology reduced the costs to where even a Part 91 weekend warrior could afford its benefits. Perhaps if you read up on it a bit more you may learn more about it?
Here's one doc... notice the date.

1716556275664.png
SL 171
 
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I had the luxury of having three different pieces of equipment in our various chemistry laboratories (Atomic Absorption, Inductively Coupled Plasma Atomic Emission, Total Reflection X-ray Fluorescence), and a raft of eager undergraduate students who needed real samples to analyze for training and educational purposes. So of course I did my own oil analysis for many years, using various methods and various analytical protocols. TXRF is the simplest method in many ways, but it is not equally suitable for every desired wear metal, and doesn't lend itself easily to high-throughput automation. The liquid sampling methods (AA, ICP-OES) are plagued with sample preparation issues like viscosity control, especially when using external standards. We learned this by cutting our teeth on biological samples, which suffer from some of the same issues. As they say in analytical chemistry: cheap, fast, accurate, pick any two.

Bottom line: it is much more difficult that you might imagine to get representative samples and to control validated accuracy due to a variety of factors, especially when trying to do this in a high throughput fashion. If we have all the time in the world to analyze samples, we can get well-validated and reproducible results. And in all those years I had the luxury of doing this very uneconomically, the data was remarkably unhelpful. Engine issues were almost always discovered by other means (oil fouling, metal in the oil filter, noticeable power changes, cylinder inspections, etc.) before any meaningful patterns could be divined from the wear metal data. The one exception: an extraordinarily high silicon reading. A torn air filter was found and replaced. So yes, it's more data, but I'm not convinced how useful it is in practice. Trying to find subtle trends in even well-validated data from data normalized for usage hours, and possibly not subjected to rigorous representative sampling is sporty at best, and an encouragement to do unnecessary maintenance at worst.
 
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Blackstone has worked well for me in a couple of planes.
 
Just as long as Blackstone keeps sending me warm and fuzzy reports on how great my engine is wearing I like em.

As soon as they send me a bad one I am through with them!
lol
Just kidding.
 
Blackstone for our Rotax 912ULS. It was fun to read the comments when we sent a sample in with 100 hours on it (which is our normal interval).
 
chemgeek said:
So yes, it's more data, but I'm not convinced how useful it is in practice.
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Interesting. However, from an industry standpoint, the use of an oil analysis has been the maintenance go-to for decades and in some cases, it is even an OEM warranty or power-by-the-hour requirement to have regular oil analysis.

While its use and acceptance is more prevalent in turbine and helicopters operations, the same benefits are there for recreational Part 91 ops as well. There are a number of industry references that detail the benefits of its use. And I’ve personally seen the results of those benefits across a number of different platforms.

However, as with any tool or process, if it is not properly used it will only provide a limited or zero benefit. Regardless it is a proven method to manage engine health at the Part 91 level and there are a number of instances out there where an oil analysis was the difference between replacing a $500 part vs a $50,000 part… or worse.
 
Jim K said:
Blackstone is one of, if not the, most expensive, but they have some advantages. They have an analyst look at the report and write a narrative instead of just sending the numbers. They will also actually read your notes and respond to them. Both things lacking with other services I've used. They do a lot of aircraft engines, and save the data by tail number, so it will transfer to a new owner when you sell. The owner is a pilot and they have several pilots on staff. I've emailed follow up questions after getting a report, and they reply promptly. Customer service is their niche.

Apparently the owner doesn't have a sense of humor though. He sent @SixPapaCharlie a nastygram over a funny video that didn't even mention them by name. I was disappointed to see that, but I don't know of anyone else that comes close service- wise, so I still use them.
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How much is Blackstone charging on average? Thanks
 
cmtejuliani said:
How much is Blackstone charging on average? Thanks
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They $35 per sample. You can get that down to I think 30 if you buy 10 at a time. It's on the website.
 
Most don't understand the purpose of oil analysis and are quick to debunk the tool. The purpose is to trend "fine particle" wear and determine which items are wearing faster than usual. In addition to that, one needs to have an understanding of the "physics of failure". How the part fails determines the type and size of metal or debris that is produced.

Oil analysis indicates/evaluates "fine" particles....measurable in parts per million (PPM). Microscopic. If your failure mode is making chunks....like tappets spalling...or the sudden plastic yielding of a bolt or any other part.....the analysis may not indicate anything abnormal.

Engines make "THREE" different size metal particles....

Large - failure modes that produce "chunks" will not find their way into the filter or metal analysis....but remain in the bottom of the oil pan and can be discovered by inspecting the oil screen.
Medium - failure modes producing granular, visible flakes, will get collected in the oil filter and can be inspected by cutting the filter.
Small - microscopic or metal not visible to the eye and measurable in parts per million....will not be seen in the filter or screen....and failure modes producing fine metal....from wear....can be detected using oil analysis.

So....one size oil indication does not fit all....as those who think oil analysis is the magic indicator.....it is but one in the RCM tool box. (RCM -Reliability Centered Maintenance)

And....the physics of failure will determine which indicator works best.

Oil analysis is but one tool to evaluate the health of an engine....cutting the oil filter and analyzing those "visible" particles sometimes is more telling.
 
Blackstone showed a sharp rise in aluminum in one of my samples. Did a good borescope inspection, and sure enough, stuck piston pin on one cylinder. Caught it before cylinder wall was out of spec. Saved a cylinder.
 
Mikey52 said:
Blackstone showed a sharp rise in aluminum in one of my samples. Did a good borescope inspection, and sure enough, stuck piston pin on one cylinder. Caught it before cylinder wall was out of spec. Saved a cylinder.
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Blackstone plus borescope saved a cylinder. A borescope without Blackstone would've done the same thing. Oil analysis added nothing.
 
OneCharlieTango said:
A borescope without Blackstone would've done the same thing.
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No it wouldn’t have. You would have lost your cylinder by the time you got your borescope out to check things. Well at least on a Continental....;)
 
That's right the next annual was 6 months away. And my son was flying it so much I was doing oil changes every 10 days or so.
 
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