@darkfixer post moved to a new “oil analysis advice” thread.
50h since Prop Strike with Shock load.
What did they actually do? If they rehoned the cylinders, you will get this.
The Copper is high, but if I understand it’s normal when using Aero Shell 15W50 + Camguard.
Not that high though. But on a re-honed engine, you will see all kinds. Does the seller have any other data?
Dan wrote:
I concur
Copper is on the high side, but so is iron. This points primarily to an engine not used as recommended by Lyco, regarding frequency and time.So, whilst these, and other, values are on the high side, it is difficult to appreciate the state of the engine based on a single oil analysis done by a laboratory with little aviation engine experience. Oil analysis is one of the tools used to show the history of said engine.
The use of 15W50 + Camguard should not produce any higher copper readings… at least they don’t in my O-360-A1A.Other items such as oil consumption, compression, and borescope inspection should help in ascertaining this engine’s health.
Red flag no, more kinda pink
According to BlackStone Labs :
Aeroshell 15W/50 oil tends to cause high copper readings in Lycoming engines. The copper isn’t poor wear from brass/bronze parts, but rather it’s a chemical reaction that happens between the oil and a coating applied to the engine parts in the nitriding process. The copper itself is harmless, but because it can mimic brass/bronze wear in a used oil analysis, it’s important to know the brand of oil you’re using to rule out actual brass/bronze wear.
Figure 7 shows the high copper trend in a Lycoming IO-360-A1A using Aeroshell 15W/50. In the most recent report, we decided
to stop marking copper in bold, given its steadiness and the likelihood that it’s just a chemical reaction in this case.
I don’t know the consumption of the oil…
Compression is 72/72/71/72
Cylinders are bore scoped without any marks or warning signs.
Dan wrote:
This points primarily to an engine not used as recommended by Lyco, regarding frequency and time.
True!
Peter wrote:
Peter
04-May-23 16:14
02@darkfixer post moved to a new “oil analysis advice” thread.
50h since Prop Strike with Shock load.What did they actually do? If they rehoned the cylinders, you will get this.
The Copper is high, but if I understand it’s normal when using Aero Shell 15W50 + Camguard.Not that high though. But on a re-honed engine, you will see all kinds. Does the seller have any other data?
2022 flown regularly until December.
Last flight was 3rd December 2022 @ 4950:20
2022 Annual was at 19th May @ 4922:66
Propstrike/shockload was done at 28th September 2021 @ 4896:45
One of the reason of higher Iron could be that it was very little flown.
Else aircraft has been flown ~100h yearly and regularly.
Owner/Pilot is 84 years old, and now he decided to stop flying.
I’m amazed that he flew that much as he did 2022 when he was 83 years old.
He has flown it around +2500h…
If we look what Black Stone Labs has for a Lycoming IO-360 A1A then both Aluminium and Iron is high…
As Dan says, nothing too bad.
Re “what was done at the shock load inspection” this is a funny one. Because, an engine can be full of rust and so long as nobody knows, it is airworthy. But if it is opened up, and they find rust, it is no longer airworthy (AFAIK, any rust, but definitely on some parts like conrods). If rust is found in the bores, and usually it is on an engine with gaps of some months, a reputable shop will remove it, by re-honing the bores. Then you have funny oil analysis values for quite a while…
But I know for a fact that not all shops will “see” rust, if you know what I mean 
I wrote about this, years ago.
Since Sept 2021 (shock load) the plane has done only 54hrs, and definitely you will see greatly elevated oil numbers at 54hrs if they re-honed the cylinders.
Arguably, one should re-hone, because one has to NDT the conrods, and while it is possible to remove the cylinders with the piston and the rings still inside, most reputable people don’t like doing it because you miss an opportunity to clean up the valves, etc.
But it could just be rust.
Peter wrote:
As Dan says, nothing too bad.Re “what was done at the shock load inspection” this is a funny one. Because, an engine can be full of rust and so long as nobody knows, it is airworthy. But if it is opened up, and they find rust, it is no longer airworthy (AFAIK, any rust, but definitely on some parts like conrods). If rust is found in the bores, and usually it is on an engine with gaps of some months, a reputable shop will remove it, by re-honing the bores. Then you have funny oil analysis values for quite a while…
But I know for a fact that not all shops will “see” rust, if you know what I mean I wrote about this, years ago.
Since Sept 2021 (shock load) the plane has done only 54hrs, and definitely you will see greatly elevated oil numbers at 54hrs if they re-honed the cylinders.
Arguably, one should re-hone, because one has to NDT the conrods, and while it is possible to remove the cylinders with the piston and the rings still inside, most reputable people don’t like doing it because you miss an opportunity to clean up the valves, etc.
But it could just be rust.
Found the documentation after Shock load inspection.
They changed bearings here and there and everything according to manufacturer etc…
Nothing about re-honing, but if this is included in the manufacturer specs then they did that too.
Little bit worried since this will be my first and hopefully last airplane I buy…
It should be fine. The worst case on an engine is a known figure. The airframe is much more important; a pile of airframe parts can cost as much as an engine overhaul.
@Darkfixer
Yes, there might be some correlation as to the increase in copper vs the oil brand used, but not that high.
As an example below, an analysis history, courtesy of AOA (Aviation Oil Analysis) of my very own Lycosaurus O-360-A1A. Of note, I’m usually using Total DM 15W50, always adding some Camguard. For 2 oil changes, namely date sampled 28-Jul-22 and 28-Sep-22, I had to use different brands, namely Phillips 66 (recorded) and Aeroshell 15W50 (not recorded by AOA).
Now looking at the copper contents, we see a slight increase of its value, say by about 1.5 – 2ppm.
What we also can observe, and this is valid for all oil analyses, is the large variation in values. This engine is flown regularly, clocked over 400hrs last year, and still, large variations can be observed, the more so for the iron contents.
Oil analysis is used to observe trends. It is one of the few tools one has to monitor his engine’s health.
Now regarding the shock load inspection, why would a shop hone the cylinders on an engine with so few hours (since last overhaul)? What they usually do is:
A nice video covering the subject here:
In addition to the above, some good read from Lycoming Why Oil Analysis Is Important
Key sentence being: The fact that is important is a sharp rise above normal of the amount of a particular metal in the oil. It is imperative then to build a case history of each engine, wherein a sharp rise in any one metal will indicate abnormal engine wear.
You always have to budget for that.
