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Engine oil analysis

Larco

Well Known Member
A friend somewhat concerned, showed this report to some of us today. We were not able to conclude if it is concerning or not.
AOA says it is normal but looking at the change caused the question.
Anyone knowledgeable regarding these reports care to comment?
Thanks
 

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If Im reading correctly not a lot of hours across 8 years. On our club planes (we have 3, ~1200 hours annually across them), have seen a subtle spike in metals when they've been sitting for an extended period (like for an avionics upgrade). I'm not an expert, but just thinking the metals increase could be from lack of use as much as use- just depends on when the hours were accumulated and how long the aircraft sits? And it's only 105 SO, so still wearing in.

One thought anyway-
 
It looks like it sat after a (or some) short flights that did not get the water out of the oil. Or started cold and taxied but did not get warm and the barrels got rusty, resulting in Fe and aluminum from the pistons sliding on the walls. A good borescope inspection could help assess.

Just a thought. A little as it is used it is a good candidate for a crankcase dryer. Ambient humidity is irrelevant.

Opinion: I don't think this is a death knell for the engine. A good inspection to ensure it is damage free and improve storage practices could return to consistency.
 
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Well, for an engine with so little use, the figures are surprisingly good... nevertheless, a few values have substantially increased, CU above all.
Past 100h since overhaul or new, values should have stabilized, and the increase of any should be wear related, or as in this case, due to little or irregular use.
Oil analysis is one of the tools available to monitor one’s engine health, and not to be overrated.

Tell him to fly more, and monitor the oil consumption... other tools are the engine analyser, borescope inspection, and the good ol diff compression check.
 
Fe could just be inactivity with a bit of rusting in cylinders. Not a big issue.

My concern would be the spike in Cu. Not too many copper parts beyond bushings and bearings.

Al is a bit concerning. In my experience, oil analysis will NOT pick up Al from the wearing pin caps, if they're even made of Al. Chunks too large for their equip. However, many Al parts in the engine and many don't point to serious issues.

Larry
 
Well, for an engine with so little use, the figures are surprisingly good... nevertheless, a few values have substantially increased, CU above all.
Past 100h since overhaul or new, values should have stabilized, and the increase of any should be wear related, or as in this case, due to little or irregular use.
Oil analysis is one of the tools available to monitor one’s engine health, and not to be overrated.

Tell him to fly more, and monitor the oil consumption... other tools are the engine analyser, borescope inspection, and the good ol diff compression check.

Second this. It wouldn't have made this many years in a humid environment. That poor engine needs usage. Operate it more, and the numbers might flatten out. Be very sure to check the screen and filter for particles. Oil analysis is hit and miss on these engines. Especially when not sampling on a more consistent basis (hours on the oil change at sample).
 
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My concern would be the spike in Cu. Not too many copper parts beyond bushings and bearings.

Larry

Just as a data point Lyc's have quite a bit of non-wear surface plating of components in the engines that can shed copper beyond the bearings and bushings. We learned a lot about this when one of our 360's started making visible flakes in the oil filter. Turns out an oil type change may react and cause some of the plating to delaminate. For us never really showed up on the oil analysis though it was visible in the filter pleats. This one made it all the way up to the Lyc lab to do metallurgical analysis on what was going on.

Thus heed the great advice that oil analysis is one component of a comprehensive strategy to surveil your engine health.

Chuck (not a mechanic)
 
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