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Filter and oil analysis - what do you think?


MooneyBob

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I always used the Blackstone lab for my oil analysis. Last couple of the, had elevated metals readings. The very last one I sent to Blackstone and AV Lab to get more results to compare. The results are almost identical, which is good. No big changes from last few analysis and almost no differences between two labs.  I also sent my filter to AV Lab. They found some flakes in it.  

Please take a look and let me know what you think. My concern is that I need to get my plane down to Naples Florida from NJ and I hope it is going to last for 6 hours. Once I am down there I can do whatever is needed it to take care of the engine. It has 940hrs since new. I will do IRAN. The engine runs strong, compression was good at last annual 100 hrs ago, oil consumption is 1qt/ 7-8hrs, oil is pretty clean after 25 hrs. I fly regularly at least once a week.  

BTW what is GRIT in the filter? It shows " major "  . 

Thanks. 

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Bob,

You are asking for people to give you an opinion based on one data point and your observations from previous oil samples. I don't know too many analysts who would give you a recommendation you are going to bet your life on with that limited amount of information. There are many questions that need to be answered such how the filter was processed, what type of wear (cutting, sliding, flaking, etc....) was observed in the wear metal particles. Also the full data set for all samples taken for this component since rebuild.  

Cheers,

Alan

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I have had engines that have pulled samples with as high iron and have been ok. I've had engines on their last leg with better oil sample results. I'd use caution, but closely monitor the engine. Change the oil every 10-12 hrs and pull a sample. 

Cheers!!

-Matt

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I think I am looking for something like " You don't have to ground the plane immediately ". I hoped to get some opinions from people with similar experiences. However, I don't know how many guys perform the oil and filter analysis at every 25 hrs oil change. 

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I would never consider tearing down an engine based on oil analysis.. Filter contents, yes. The report shows filter contents to be within normal limits.. I would change the oil and filter frequently and have a good engine mechanic examine the filter contents. Cam and lifter wear/ corrosion would not be expected to result in catastrophic failure if in fact you have that.. 

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Bob

i suspect you are between oil changes, but if you still have the oil drained, I would check the oil screen just to be sure there is nothing bigger there.  I suspect there is not, but it helps feeling better about things.   Ultimately it is your choice on what to do, but it seems that flying 6 hours in cruise is probably less stress on an engine than the typical 6 hours we might do in local flying.  So, if your plan is to fly aff another 10-25 hours to check your oil anyways, then doing in cruise might be a nice test to see what things look like.  It might make you feel better to plan your flight using airports as waypoints.  I've done that on occasion...mainly weather, but it works for mechanical feel good too....you always know where you can land if something just doesn't feel right.  As Alan said, we don't see the full trend here or what your filters looked like....so hard for us to make a recommendation.  

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2 hours ago, mooneyflyfast said:

I would never consider tearing down an engine based on oil analysis.. Filter contents, yes. The report shows filter contents to be within normal limits.. I would change the oil and filter frequently and have a good engine mechanic examine the filter contents. Cam and lifter wear/ corrosion would not be expected to result in catastrophic failure if in fact you have that.. 

Yes. That's what I am going to do. I will pull the jug(s) and take a look at the cam and other things. I bought the plane with a new engine that saw little activity in 15 years. I put 500 hrs on it with no issues but the cam is probably giving up by now. 

Thank you.

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2 hours ago, takair said:

Bob

i suspect you are between oil changes, but if you still have the oil drained, I would check the oil screen just to be sure there is nothing bigger there.  I suspect there is not, but it helps feeling better about things.   Ultimately it is your choice on what to do, but it seems that flying 6 hours in cruise is probably less stress on an engine than the typical 6 hours we might do in local flying.  So, if your plan is to fly aff another 10-25 hours to check your oil anyways, then doing in cruise might be a nice test to see what things look like.  It might make you feel better to plan your flight using airports as waypoints.  I've done that on occasion...mainly weather, but it works for mechanical feel good too....you always know where you can land if something just doesn't feel right.  As Alan said, we don't see the full trend here or what your filters looked like....so hard for us to make a recommendation.  

Yes. I just changed the oil. I will fly few hours locally before I fly down to my new location in Florida. I will change the oil and check the screen before the trip. The good thing is that my home is my hangar now and I can work 24/7 on the engine in good warm conditions. 

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1 minute ago, MooneyBob said:

Yes. I just changed the oil. I will fly few hours locally before I fly down to my new location in Florida. I will change the oil and check the screen before the trip. The good thing is that my home is my hangar now and I can work 24/7 on the engine in good warm conditions. 

Tell us more.  Are you moving to an airport community? 

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There is one nice thing about when the cam starts to go...

the lobes lose their hardened coating.  This causes the wear to significantly increase. The wear is more like bits...

The bits have been known to show up in the filter.  As in fill a tea spoon with metal.

Since the cam is no longer actuating the valves as much, the power is going away more each hour of operation...

T/O distances will get measurably longer, climb rates will be a bit slower.

OAT will have a way of masking the changes.

Other bits that may show up in the filter are carbon chunks that come from other places in the engine...

Stuff I learned about on MS...

PP, no mechanic.

Best regards,

-a-

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19 hours ago, carusoam said:

There is one nice thing about when the cam starts to go...

the lobes lose their hardened coating.  This causes the wear to significantly increase. The wear is more like bits...

The bits have been known to show up in the filter.  As in fill a tea spoon with metal.

Since the cam is no longer actuating the valves as much, the power is going away more each hour of operation...

T/O distances will get measurably longer, climb rates will be a bit slower.

OAT will have a way of masking the changes.

Other bits that may show up in the filter are carbon chunks that come from other places in the engine...

Stuff I learned about on MS...

PP, no mechanic.

Best regards,

-a-

Thank you A.

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It takes quite a while to notice performance loss.  But continued operation while making metal will impregnate your piston skirts with steel bits, eventually destroying your pistons and will score your cylinder walls.

 Lycoming has an SB which defines allowable metal in the filter, it's quite generous, but then they sell engine parts.  If you have ferrous particles on a second filter check, stop and find the source and repair it, it won't get better.

Clarence

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Interesting question to think about.  Using my inch-deep expertise, I wouldn't dare give real maintenance advice but instead view it as a learning exercise.  To me, the scenario seems consistent with very early cam/lifter spalling: i.e. elevation in Fe, no simultaneous Al or Cr elevation to suggest a cylinder source, no other elevated metals, minute ferrous flecks in the filter.  I'd be curious to hear alternate hypotheses from others though.  

Assuming my conclusion is correct (repeated disclaimer - not an expert), I personally wouldn't hesitate to fly it 6 hours somewhere - per my understanding, sudden catastrophic failures from cam-lifter spalling are basically unheard of even when it gets advanced.  It's possible the oil analysis caught the spalling very early, and the cam is about to come apart and show you a bunch of visible metal in the filter and/or screen at next oil change.  But the spalling won't kill you, just badly bruise your wallet.  And if it's early spalling, there's also not a thing you can do to prevent it progressing at this point. In your shoes, maybe I'd stay away from high DAs and short runways, given risk of subtly decreasing power until the issue sorts out.

Caution- opinionated internet rant: Through my ownership experience thus far, I have developed a distaste for the routine oil analysis that I keep paying for because it is the prevailing dogma to do it. Assuming you have an early spalling cam, the extra lead time on your problem provided by the analysis doesn't seem to help your safety or or your sanity. You will do little that's different because of it unless the engine shows issues in operation or a bunch of metal shows up in the filter. If that doesn't happen, you will still (quite naturally) feel anxious about flying until that Fe level comes back down in the oil - and if it comes down, I think you would also have been better off never knowing about it in the first place.   Related anecdote on my end - The Fe, Cr, Al, Ni elevation pattern on my oil analysis gave me over a year of lead time on the cylinder work I'm having done now - it suggested problems with both rings and a valve guide.  But the info it provided was nonspecific and minimally actionable - kinda like your current predicament.  By contrast, my tracking of rising oil consumption, routine borescopy, engine monitoring, and finally compressions at annual last week diagnosed my issue with better specificity and ample time to spare before it became dangerous.  The clean filters over the last year provided hope all along that it wasn't going to be the dreaded overhaul.  Oil analysis in retrospect added nothing as long as I did the other routine stuff.  

Sorry about the rant, and good luck!

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Wash the filter element in a quart plastic bucket full of mineral spirits . Then put a very large magnet under the cup and pour off the liquid, most of what's left is your ferrous metal. The metal is there, but the cursory visual inspection and run in a stick magnet down the pleats doesn't see it. If you're about to spend between 8-30 grand to fix the problem, then a little more preciseness in diagnosis is a good thing. 

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42 minutes ago, jetdriven said:

Wash the filter element in a quart plastic bucket full of mineral spirits . Then put a very large magnet under the cup and pour off the liquid, most of what's left is your ferrous metal. The metal is there, but the cursory visual inspection and run in a stick magnet down the pleats doesn't see it. If you're about to spend between 8-30 grand to fix the problem, then a little more preciseness in diagnosis is a good thing. 

That's exactly what I did two oil changes ago following your advice from different topic on MS. I used your method ( which I like a lot) and very strong rare earth magnets. It picked fair amount of " metallic substance ". Not really visible metal parts ( see picture) . But together with elevated metals in the oil and last filter analysis done by the AV Lab I will do compression check, borescope with good camera and probably pull the cylinder to check things out. As Clarence and DXB says it will not get better. Now I just have to diagnose the issue precisely so it is not waste of time and money to get it right. 

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On 12/25/2016 at 4:01 PM, MooneyBob said:

That's exactly what I did two oil changes ago following your advice from different topic on MS. I used your method ( which I like a lot) and very strong rare earth magnets. It picked fair amount of " metallic substance ". Not really visible metal parts ( see picture) . But together with elevated metals in the oil and last filter analysis done by the AV Lab I will do compression check, borescope with good camera and probably pull the cylinder to check things out. As Clarence and DXB says it will not get better. Now I just have to diagnose the issue precisely so it is not waste of time and money to get it right. 

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Ah- I remember that pic now from a previous thread-  that's a dramatic amount on the magnet- would freak me out a tad.   And yet it's  mostly carbon flakes  pulled along by minute embedded metal particles?  I've never heard of this phenomenon - not sure I recall a good explanation from the prior thread either.  And the screen was clean?  I hope someone here can shed insight....

I've had Fe elevated even higher than yours in the past,  but nothing from the filter ever stuck to a very strong magnet, despite some carbon flecks being there.  

Also I think one has to pull both front and back cylinders to see all the cam lobes and lifter faces? What an expensive PITA, particularly  if they turn out to be ok.

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21 minutes ago, DXB said:

Ah- I remember that pic now from a previous thread-  that's a dramatic amount on the magnet- would freak me out a tad.   And yet it's  mostly carbon flakes  pulled along by minute embedded metal particles?  I've never heard of this phenomenon - not sure I recall a good explanation from the prior thread either.  And the screen was clean?  I hope someone here can shed insight....

I've had Fe elevated even higher than yours in the past,  but nothing from the filter ever stuck to a very strong magnet, despite some carbon flecks being there.  

Also I think one has to pull both front and back cylinders to see all the cam lobes and lifter faces? What an expensive PITA, particularly  if they turn out to be ok.

Of course it did freak me out first. I stopped flying immediately and was afraid even taxi. Then I took a closer look and didn't really find any substantial amount of the metal particles even with the magnifying glass. I use the tempest filter with the magnet and it has absolutely no traces of metal on it. Then I have posted it here and got no real answer or explanation. Then I asked for used filter from my friend ( different engine - Continental 540 I think ) and did the same thing. The magnets picked similar substance from the filter but the amount was smaller. Maybe 1/3 of mine. But it still was there. I flew 25 hours since then, sent the oil to two different labs ( similar results - elevated iron but not catastrophic) and sent the filter to the AV Lab ( see top of this topic). 

Since there is no dramatic change in the amount of metals I will fly down to Florida to my new location and take it from there. Compression check , bore scope, cylinder removal, IRAN, ...

Thanks.  

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Bob,

I'll play devil's advocate here a bit more, for discussion purposes .  

I know expert folks here have said that a cam or lifter that's coming apart will produce abundant, visible metal in the filter when the damage really gets going. Prior to that, there is no added risk in flying, and even when it's really coming apart, the risk is modest. Based on my believing this notion, I quit washing my cut filters in mineral spirits and straining through a shop towel.  I would always detect a few small shiny flecks to worry about, usually nonferrous ones, that I never saw in the pleats by eye.  Your filter washing technique is different however. In my case the very small ferrous flecks might have dissociated from the carbon and/or run through the towel -  I can't say that I wouldn't get the exact same outcome you did if I tried it your way. Your buddy's filter producing a similar result certainly supports the possibility that the technique is overly sensitive for detecting ferrous metal. Further , the Lycoming SB on what to do about various amounts of metal in filter does not seem to apply if you are using this super sensitive technique to detect them.

So I have to question - why investigate any further at this point? You saw an isolated elevation of Fe on your oil analysis and then performed a maximally sensitive technique to detect iron in your filter that can't be seen directly, and there is no rational standard on interpreting the information that it gives. If you had never sent oil analysis but just carefully looked in the pleats of your filter at oil changes, you would have no concern at all right now. It runs great, oil consumption is great, minimal blow by etc. 

I am not convinced any further investigation, or even an oil change interval shorter than 25 hrs, is warranted now. Routine borescopy seems worthwhile to check the valves but is unlikely to shed further light on this particular situation. I also don't see benefit of doing compressions here prior to annual and certainly would be in no rush to pull one or more jugs. The anxiety of cutting your filter the next few times will be far less unpleasant than the primal scream that will come with pulling 2 jugs only find a pristine cam and lifters.

Maybe the experts will convince me that this approach sacrifices some safety, and I welcome being corrected - but I don't see it yet. 

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Do we know anyone with NMR experience?

These are the people making medical images from using strong magnets....

I think we may have uncovered some particles can show a slight magnetic nature when exposed to a very strong magnet.

It would be interesting if the photos of the 'carbon' bits being attracted to the magnet were sent to the oil experts. The guys that know what to look for in oil.

ask if it is possible to magnetize carbon?

Best regards,

-a-

 

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13 hours ago, jetdriven said:

The primal scream after opening up the engine to find the cam, lifters, Pistons, cylinders, governor, and prop are all trashed is far louder. 

Is there a reasonable case here that Bob's engine is about to unleash a huge amount of metal into the oil beyond the cleaning capacity of the filter and screen?   It seems plausible to me if he simply ignores visible metal in the filter, but that is not the situation here.  He sees nothing visually in the filter, but pulls up a lot of non-metal material that may contain minute embedded Fe particles to the magnet, using a technique that has no standard I'm aware of for what is normal. He also has persistently elevated Fe alone on his oil analysis, and "minor" alloy steel on direct analysis of the filter. I still don't have clear context for how to use this information other than watch the filter and live with extra anxiety.  

 Lycoming's guidance on metal in the filter is of little help here as far as I can tell. SB 450E on oil filter inspection merely states: "Check condition of the oil from the filter for signs of metal contamination. Remove the paper element from the filter.  Carefully unfold the paper element and examine the material trapped in the filter." So Lycoming's guidance on intervals to recheck vs. take out of service based on metal seem derived entirely from this mode of filter inspection.  Based on that particular standard, Bob doesn't even need to shorten his oil change interval.  If his situation portended imminent destruction of multiple engine components from widespread metal contamination, I suspect that standard would be more stringent.

Of course that's just a couple of documents from Lycoming, which can be opaque in their reasoning, and  I suspect you've studied the issue a  lot more than I have.  Is there a case to use a more stringent standard to pull jugs and look directly at the bottom end in Bob's situation?  It doesn't seem that he has any other alternative to this presently other than watch and wait.  

 

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