Help with oil analysis

[SkyHog]

Anyone wanna take a look at this and tell me if the rise in metals is a cause for concern? I've never looked at an oil analysis before:

 

[DoubleD]

What rise? Seriously, looks like the values are bouncing around within their normal range. It's maybe a little bit of a concern that several seem to be near their upper range at once, but there's no sign your engine is self-destructing. My advice: do nothing and continue to monitor.

 

[C-1 PILOT]

I use AOA also. I see no need for concern at this point, but would monitor the next analysis. If that seems high you might want to do the oil change after that one at 25 hours and see the results.

 

[wsuffa]

I'm with C1.

Those sets of samples were pretty far apart.

I'd establish a new trend line and do the sampling with each oil change for a while to see what "normal" is. If you're really concerned, sample at 25-30 hours, then again with the oil change.

 

[Henning]

Anyone wanna take a look at this and tell me if the rise in metals is a cause for concern? I've never looked at an oil analysis before:

Well, the only thing I didn't like is the rise in copper, tells me you're starting to get into the core of the bearings, but it's not a major issue at this time. Keep an eye on this, if it keeps trending up, it's time to do a bottom end while your crank is still good.

BTW, does your engine have chrome cylinders?

 

[Let'sgoflying!]

1. How much faith do you folks put into the company's recommendation codes; "100.. All values appear normal"

2. I have often wondered if these companies assume just a little bit of risk by offering an interpretation of the tests. Would their attorney not suggest "Just give them the numbers, let them decide what to do with them"?

3. I called one of these sampling companies once and asked them if they had very many cases of where abnormal results detected an impending problem and the person on the phone could not say. I got the impression that it wasn't a matter of this person not knowing, but that there really hadn't been much talk of 'yep, that test saved their bacon... one more flight and the engine wouldve cratered'. I do the tests but have always questioned their value. Seems like they are more valuable to a potential buyer!

 

[Henning]

1. How much faith do you folks put into the company's recommendation codes; "100.. All values appear normal"

2. I have often wondered if these companies assume just a little bit of risk by offering an interpretation of the tests. Would their attorney not suggest "Just give them the numbers, let them decide what to do with them"?

3. I called one of these sampling companies once and asked them if they had very many cases of where abnormal results detected an impending problem and the person on the phone could not say. I got the impression that it wasn't a matter of this person not knowing, but that there really hadn't been much talk of 'yep, that test saved their bacon... one more flight and the engine wouldve cratered'. I do the tests but have always questioned their value. Seems like they are more valuable to a potential buyer!

Here's my take on oil analysis: It is great for figuring out when parts (especially bearings) are starting to wear, this lets you change them out before too much colateral damage is done (like a scored crankshaft). Like in his report, what I read is bearings are starting to wear into base material (rising copper) and the rings are starting to wear quicker (rising chrome and nickel).

As far as finding that an engine is about to lunch out, that is more readily caught on the filter inspections.

If it was mine and I had an O/H kitty ready, I'd be making arraingements for O/H within a year or so, maybe now if it was my slow season and I was looking at heavy usage next season. If the copper rose again next time, I'd go ahead and do it and save the cost of a crank. If the iron goes up as well, it's definitely time.

 

[Let'sgoflying!]

Seems reasonable Henning, ps I just found the AOPA article on the topic, near the back.