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Oil analysis. Yes or no?

AAflyer

Well Known Member
I've been flying my -8 for almost 3 years, with only very minor issues. My new IO-360, with dual P-mags runs great. I cut open my oil filter every other oil change, and have found decreasing metal on each inspection.
I have never submitted my oil for a lab analysis, but is something I've always considered.
My questions are: , is it worth the effort if the filter is clean?
Who do you use?
Pros...cons...?
Thanks.
 
It isn't worth it if you're only going to do it once or if you wait until you suspect a problem. Oil analysis is about identifying trends, and you'll need regular data points to establish base line numbers for your engine.

I've been using Blackstone Labs. Quick turnaround (usually about a week), and I've appreciated the analysis and interpretation of the data they've given beyond simply "here are the numbers".
 
Oil Analysis

Bruce:

I just recently started oil analysis every other oil change after "Widget" sent his engine down to JB Engines to be topped. Never shown any metal in filters. Turns out engine was trashed. JB sent pics back. The metal turned out to be so fine .. like black mist ... maybe not even able to get with a magnet.

I cut my filters on every change but now I use a large magnet and oil analysis every other change. Want to see if there is a trend.
 
As Barrett has mentioned, it is most useful when it is done on a regular bases to see the trend. I have been doing it and I think it is worth it, small fee to catch things early if it was going to go south.

I use Blackstone and they have been great in providing useful info as what the report means.
 
Mike Busch recently suggested on a newer engine do it every 3 or 4 oil changes if you are flying regularly. Kind of made sense to me, but everyone has a different opinion on tjis subject.
 
I've never had anyone suggest I pull their engine and have it overhauled based on an oil analysis,
IMO it just gives folks something else to worry about especially when flying at night or over water :eek:
 
Too much information?

No, I want all the data I can get. I won't let the analysis spook me, since any abnormality will be further checked. If you fly 100 hours a year, it will only cost $50 per year. Do it every other oil change and the cost is insignificant. Personally I don't think this is an area to cut costs.
 
I've never had anyone suggest I pull their engine and have it overhauled based on an oil analysis,
IMO it just gives folks something else to worry about especially when flying at night or over water :eek:

Or to give you added confidence, if the analyses show good trends over time.

Personally, I'd rather know more than less about any component of the system my butt relies on, so that I can make informed decisions and risk evaluations.
 
Yes.
The oil filter picks up big stuff, Oil analysis detects a different type of wear that an oil filter inspection will not, and visa versa. They are equally important condition monitoring tools to detect a problem before it becomes a safety of flight issue.
 
I keep a small sample of oil from every oil change. If I ever notice anything out of the ordinary going on I can always send samples in for analysis, even going back in time.
 
As Barrett has mentioned, it is most useful when it is done on a regular bases to see the trend. I have been doing it and I think it is worth it, small fee to catch things early if it was going to go south.
Remember this is about trends not absolute numbers. But there have been occasions where an issue was identified with oil analysis before a problem happened. When I was in the USAF as a RADAR technician we did periodic oil analysis on the massive electrical motor that rotated the RADAR antenna. One day we got a note they were sending us a replacement motor because the oil analysis showed a main bearing was failing. We replaced the motor and sent ours back to Depot. They later reported the analysis was correct and one of the main bearing was so bad it probably would not have lasted another month. Since then I have been sold on the program. Thankfully my airplane engine oil analysis has always come back normal. The way I see it the $12.30 I spend every 6months for oil analysis is an insignificant cost of airplane ownership. YMMV

I use Blackstone and they have been great in providing useful info as what the report means.
FWIW I use Aviation Oil Analysis (AOA) by ALS Tribology instead. No real reason to use one over the other, just stick with whichever you start with. Remember it is all about establishing a trend so anything different quickly sticks out.

33f7.jpg

They also provide a graphic display of all the items for easy trend analysis. I just didn't want to upload all the graphs from each item.

:cool:
 
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I consider it a tool in the box. Like the official Lycoming position says, don't forget your other tools. The oil analysis trend on an engine I owned showed a sudden slight increase in wear. So we grabbed another tool, and scoped the cylinders, which showed suspicious markings. So we grabbed another tool, and pulled cylinders, found further wear issues. General consensus, given the indications and time on the engine, was to do an overhaul. Just my experience. I use Blackstone, no complaints.
 
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