Why are there increased levels of copper in my oil?

Recent oil analyses seem to be showing increased levels of copper coming from my XP-360. Could you help with a diagnosis?

Steve Glasgow-Cappy

via email

I’ll shoot from the hip on this one because I need more specific information to answer your question, but let’s see what we can do.

How about I just throw out a couple of questions that you “”can answer in the privacy of your own home”” and see if you can put your finger on the source of the higher copper level in your spectro analyses?

• How many hours are on this engine?

• What is the frequency of your oil and filter changes and do you always do an oil analysis when changing your oil?

• When did you begin to notice this increase in copper and has it increased at each analysis?

• What brand and type of oil are you using?

If you’re using AeroShell 15W50 this may explain the reason for the increase in copper levels because this is a strange phenomenon that occurs when using this product. This is not to mean it’s a negative in any way, but it has been known to increase copper levels when compared with other oils. Again, this is nothing to be concerned about if you are using this particular brand of oil.

If your copper level went up a few PPM and has hovered around that point and is showing no further increase, I wouldn’t worry too much about this, but I’d continue to monitor it at each oil change.

As I mentioned at the outset, this is kind of like shooting in the dark, but maybe it will give you some place to begin and possibly put your mind at ease if you’ve got the right answers to the above questions.

Paul McBride, recognized worldwide as an expert on engines, retired after almost 40 years with Lycoming. Send your questions to: [email protected].