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Bad oil analysis results

Lemos

Active Member
I received bad news in an email from Blackstone. Looks like my engine is making metal. How bad are these values?

Aluminum 18 ppm. Iron 77 ppm. Copper 30 ppm. Nickel 11 ppm. Everything else is OK.

Blackstone notes: we have found high levels of iron and nickel compared to averages. Check the compressions, and check the oil filter. Resample in ten hours.

What am I looking at here? Engine overhaul? Is there a market for an airplane with an engine with these kind of problems?
 
What did you find in the filter pleats? Oil analysis is complementary to actually cutting the filter and shouldn’t be used in isolation.
 
I’d check the compressions, check the oil filter, maybe have it borescoped, and re-sample in 10 hours. I think I’d start making plans for an overhaul only based on a demonstrable trend, not a single oil sample.
 
above

Well oil analysis did its job - I do it every oil change

Do as directed - check the filter and finger screen for any particles. Clean oil and resample as directed.

Have you done several oil analysis or is this the first one?

Its all about trends - chill for a bit but be safe
 
I received bad news in an email from Blackstone. Looks like my engine is making metal. How bad are these values?

Aluminum 18 ppm. Iron 77 ppm. Copper 30 ppm. Nickel 11 ppm. Everything else is OK.

Blackstone notes: we have found high levels of iron and nickel compared to averages. Check the compressions, and check the oil filter. Resample in ten hours.

What am I looking at here? Engine overhaul? Is there a market for an airplane with an engine with these kind of problems?

Before you go off the deep end, you need to answer some questions like what oil and viscosity are you using, what climate are you mostly operating in, how many hours on the oil, how long has the oil been in the engine, what has been the oil temps generally, How many hours on the engine, was this the first sample, How long do you normally fly each time, what engine maintenance has been done recently. Those PPM numbers are not high enough to condemn this engine or get excited until you find out what you may be doing to push these numbers up. george
 
Looks like my engine is making metal

Well, there ain't no in service engine not making metal... the term being normally used when visible metal of kind is found in either the oil itself, or/and the filter(s)

How bad are these values?

They are high, but I've seen way worse

Blackstone notes: Check the compressions, and check the oil filter. Resample in ten hours.

Have you checked the compressions, have you checked the oil filter, have you resampled after 10 hours, results?

What am I looking at here? Engine overhaul?

Probably not. Too many unknowns here. The top missing clue is: How many flight hours on that engine prior to the oil analysis, in say the last year, 1/2 year, months? I have seen very hi iron contents, in engines not used for say 3 months, then flown some, and having the analysis done. Most of the time rust scraped off the cylinder walls by the piston rings...

Is there a market for an airplane with an engine with these kind of problems?

There always is "a market"... just airplane type/state/avionics/engine/time available for sale/etc dependent...


As already stated, oil analysis is one of numerous tools used to assess an engine's health, and certainly not to be used on its own.
 
This is why we do engine oil analysis. You’ve discovered a possible problem, and it may be operator induced, or not. I think you should follow the recommendations given to start to figure it out. The good news is, you can still fly - following the recommendations from professionals, and you are still safe if you follow this advice. SAFE…. That’s why we do it. Good job!
You might want to give Savvy a call. They’ve helped countless aircraft owners with similar problems, and one of their goals is to not do any invasive engine maintenance if not needed. Do your due diligence, give them, or someone else the info, and let them help you.
 
This is why I think oil analysis is pretty much a waste of money, no one has ever torn down an engine based on oil analysis, so all it does is give you something to worry about. Keep flying it and follow Lycoming recommendations checking screens/filters etc., if done routinely you'll end up with the same result.
 
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This is why I think oil analysis is pretty much a waste of money, no one has ever torn down an engine based on oil analysis, so all it does is give you something to worry about. Keep flying it and follow Lycoming recommendations checking screens/filters etc., if done routinely you'll end up with the same result.

Walt makes a good point, additionally it is critical that the sample be taken at the proper time during the drain. We had a mechanic who forgot to take the sample during the drain, realized his mistake and retrieved the sample from the oil filter. Results came back extremely elevated.
 
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Thisis the opposite case, but it is the source of my mistrust of oil analysis, in the short run.

One time, I was starting an annual inspection, took the oil sample, sent it out and proceeded to drain oil through a paint strainer and to cut open the filter. The amount of metal present meant the engine obviously had a problem. Proceeded to engine tear down and found a spun main bearing. The engine was likely only a couple of hours from a stoppage event.
A couple of weeks after the start of the inspection, got the analysis back, slightly elevated levels, recommended checking again at 25 hrs. No sign of the imminent failure.

In essence the analysis by itself was pretty useless.
 
This is why I think oil analysis is pretty much a waste of money, no one has ever torn down an engine based on oil analysis, so all it does is give you something to worry about. Keep flying it and follow Lycoming recommendations checking screens/filters etc., if done routinely you'll end up with the same result.

Sorry, but I disagree. An oil analysis is a point of reference that can have very meaningful information. No one that has a basic understanding of engines says that an oil analysis is a reason for an engine tear down - except maybe a mechanic that has only his/her interests in mind. But it might be a reason for further investigation and concern. That is what almost all responders to this post has recommended - further investigation. All of the engine experts that I have dealt with consider an oil analysis a valuable part of the whole scheme of engine maintenance and health monitoring. I doubt that most engines that are about to fail because of internal mechanical problems would have an oil analysis that looks good. The problem and correction may be something simple, but it needs to be looked in to and remedied before something more serious develops.
That’s why we do oil analysis…..
 
This is why I think oil analysis is pretty much a waste of money, no one has ever torn down an engine based on oil analysis, so all it does is give you something to worry about. Keep flying it and follow Lycoming recommendations checking screens/filters etc., if done routinely you'll end up with the same result.

I have a data point to support this. Ten years ago, I did an oil change, and found notable metal (ferrous) in the filter. I sent in the oil analysis in anyway out of curiosity, and all was normal. However, the crankshaft gear was grinding itself up. It was only hours away from an engine failure. There are certainly data points to support both sides of this.
 
Thisis the opposite case, but it is the source of my mistrust of oil analysis, in the short run.

One time, I was starting an annual inspection, took the oil sample, sent it out and proceeded to drain oil through a paint strainer and to cut open the filter. The amount of metal present meant the engine obviously had a problem. Proceeded to engine tear down and found a spun main bearing. The engine was likely only a couple of hours from a stoppage event.
A couple of weeks after the start of the inspection, got the analysis back, slightly elevated levels, recommended checking again at 25 hrs. No sign of the imminent failure.

In essence the analysis by itself was pretty useless.


Useless? I don’t agree. If you found an amount of metal in the filter that questioned the integrity of the health of the engine, why would you send out a sample for analysis, except to figure out where the problem existed, but either way, the airplane is downed until further maintenance is done.
After your further investigation you decided on a tear down. Obviously needed because of a spun bearing. A spun bearing doesn’t mean the engine will fail within the next couple of hours, but you made the right choice, obviously. Did you also send the oil filter to the oil analysis company? If not, why would you say that their analysis is useless? If they didn’t get the contaminated filter, they didn’t get the full story.
I’m just saying that this idea that oil analysis is useless is flawed. There is very meaningful information here, but it is a starting point. It is the finest point of the filter, along with borescope, to analyze the health of our engines. I don’t think we should down play it.
 
I have a data point to support this. Ten years ago, I did an oil change, and found notable metal (ferrous) in the filter. I sent in the oil analysis in anyway out of curiosity, and all was normal. However, the crankshaft gear was grinding itself up. It was only hours away from an engine failure. There are certainly data points to support both sides of this.

My experience as well.

A few cold starts will throw off the numbers. I do not do oil analysis as there is plenty of information provided by a cut open or cleanable filter.

I also do frequent borescope inspections and would see any issues top-end-wise.
 
Maybe you did not fly it for a couple of months after a run in cold weather.

Filter, screen debris is the indicators for immediate action or observation, depending on precisely what is found.

I swear by an analysis to indicate if operating procedure, cold starts, air leak around the filter, or parked too long without a dehydrator.

The nickel is what puzzles me about your results. AL, Fe, could say possibly cylinder rust from being parked. Copper - maybe dissolving copper from the camshaft or something else. But the nickel - - the only thing I can think of is the nickel bond barrier coating on the rod/main bearings. Or from a nickel cylinder coating. Either way - - as part of the big picture w/o supporting indications from the screen/filter inspection, then an operation procedure change might be in order.

Full disclosure- I got an alert for Al, Fe and Chrome from my last analysis. It was only 30 hours but I flew 20 of that through smoke and haze on a west coast trip. On landing I had a heavy coating of ash following one leg. Physical inspections showed nothing different, in fact 4 tiny shiny specks on the filter was all. So, back to normal operating procedures and will check again at the next oil change. When I changed from W100 to 15w50 aeroshell - my copper jumped, as did my friends 10. eh.
 
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Sorry, but I disagree. An oil analysis is a point of reference that can have very meaningful information. I doubt that most engines that are about to fail because of internal mechanical problems would have an oil analysis that looks good. ..

Early on I used them. At 100 hours, analysis came back all good with smiley faces. Inspection of filter showed large amounts of Aluminum particles. Piston pin caps were wearing away rapidly and had to be replaced. I believe they use a mass spectrometer and it cannot see large particles, only microscopic ones. Please dont rely solely upon oil analysis.

Lary
 
Early on I used them. At 100 hours, analysis came back all good with smiley faces. Inspection of filter showed large amounts of Aluminum particles. Piston pin caps were wearing away rapidly and had to be replaced. I believe they use a mass spectrometer and it cannot see large particles, only microscopic ones. Please dont rely solely upon oil analysis.

Lary

Exactly. It’s just one tool to help you, and should always include oil filter inspections and a horoscope inspection when needed.
 
Exactly. It’s just one tool to help you, and should always include oil filter inspections and a horoscope inspection when needed.

"horoscope inspection" :p

I realize that was an auto-correct typo but considering the ambiguous nature of some engine diagnostic techniques perhaps consulting a horoscope wouldn't be such a bad idea. :rolleyes:

LOL
 
With oil analysis, it is really about the "trend in the metal...over time" in the oil.

Immediate catastrophic damage produce very large chunks of debris but not the super fine microscopic parts...the spectrograph analysis is really good at looking at the microscopic super fine particles. I presume the SOP at the lab is to shake well the oil sample before looking at the sample.

If your engine has sat for a long time and then you started flying again it will have high metal and then the metals will start to lower with more recency of hours. Same if there was a new cylinder installed.

These are really good:

https://www.youtube.com/watch?v=ibX8xJYxsSA

https://www.youtube.com/watch?v=AEGyN2U3FSM

When you cut open the filter to inspect the paper element take the bare element and first squeeze it in a vice to press out the extra oil and that will make the inspection of the pleats more easy and accurate.

When you drain the oil it is always good to drain it through a fine mesh screen or cheese cloth (way more messy) and closely look at the screen to see if any chunks are coming out. Also look at the strainer.
 
I agree with Walt, having got some advice from my engine builder when I asked about oil analysis:

Oil analysis is great for trend monitoring if you are operating consistent hours in a consistent environment, like an enclosed generator set or mining haul truck in the Pilbara. But any Cat mechanic will tell you all operators and mechanics do the same thing, which is replicated in Aviation word for word... If a concerning report comes back, they change the oil and inspect the filter, all being ok ,send it back out for a set period of time and retest. We have never seen an aircraft engine grounded on the findings of an oil analysis report, only by what is in the actual filter or suction screen so it does beg the question, why do it in the first place?

I've been happy to go with his advice -- He didn't get to be a builder of Matt Hall's Red Bull Air Race engines without knowing what he was talking about.

- mark
 
Oil Analysis is just a tool. It's a snap shot in time and cannot predict when a rod is going to let go or a valve is going to get stuck and so on. I think many people have the wrong expectations from it.

I have used oil analysis since the sixties, starting in the USAF as a jet engine mechanic. We would remove engines based on sample reports and they were spot on when we tore the engine down. The report would say #4 bearing is coming apart for example, based solely on the type of material that the engine was making. I have since used oil reports to extend maintenance on all kinds of ground equipment over the last 40 years, sometimes taking engines out of service due to early warnings from increased material coming from cracked heads in gas engines and liners in diesel engines. A pilot could extend oil changes on their aircraft if the lab provided enough info to determine the condition of the oil and additive package, but many aviation type labs do not give you enough info to safely do it in many cases.

So, is it worth the cost of doing this in your aircraft? It really comes down to your thinking on using it as a tool, being able to interpret the readings, and keep in mind that it is not a crystal ball.
george
 
Thread drift...

Agree with the recommendations of others here.

I'll add that a history and trend of oil analysis adds significant value to high time engines especially given oil/filter changes may be competed and documented by the owner/pilot...a person that may not be skilled in filter/screen analysis. It involves a 3rd party and is well documented and objective. If I were to sell my aircraft today, I would certainly recoup the cost of all my samples and give the future owner some confidence in the lower end of a machine that was field overhauled in the early 90's

I was very skeptical about the engine when I bought the airplane...it had been sitting as a part of estate, with only the occasional flight or engine run. I really lucked out, because I took a chance in return for a discount as a result of it history.
 
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