I recently changed oil, took an oil sample and was surprised by a moderate uptick in copper in the UOA results. A question for Bird Shot or another expert in the field: What bearing/component is the most likely donor of the copper in an AP1?

The number went from a consistent 2-4 PPM (over 85,000 + miles) to 13 PPM. While 13 PPM is not a significant quantity, and is well below any notable concern level - I would still like to think ahead just in case this becomes a trend. Obviously, I will keep tabs on the copper levels to see if this was a one time blip, a new "normal", or if the numbers keep climbing. I would just like to know what the most likely source (sources) of copper are in the AP1 motor.

Thanks.

 

Isn't it the main crankshaft bearings?

 

To be copper content it would have to be bearing related.

 

Did you see anything in the drain pan or oil filter? If not, I wouldn't get too excited. Wait to see the next UOA.


Also, jfusion has some experience with UOA'S just prior to bearing failure. Maybe he can be of some help. Good luck!

 

birdshot is another UOA guy

 

I wish I knew where the copper might be coming from in these engines but it's hard to say, I have never had one apart. There are so many sources of copper in general from engines but since crank bearings typically have a copper layer they are often looked at as a likely source.

If it's just copper your seeing from metals testing, I wouldn't necessarily say its from a bearing. I believe the S2000 uses traditional babbitt type bearings and for you to have a bearing specific issue developing you would see lead or tin first and/or in conjunction with copper (and probably at higher levels than Cu). Here is a good link on engine bearing materials that will help to visualize why this is. If you get to the copper, you have often first worn away the mostly lead overlay. Where else the copper is coming from in this car specifically I cant say however. (oil tubing, fuel lines, valve train??)

Leaching is a common source of copper "wear" and is basically harmless. I have looked at diesel engine oil samples with 600+ PPM Cu showing in spectra analysis under microscope magnification. Even at 1000x magnification, these samples will have zero evidence of copper wear particles of any kind, Cu is easily identified otherwise.

This is not to say it's not from a main bearing, but for me, I would only start to worry if I was seeing equally high or higher PPM of lead/tin or possibly nickel. What were those levels?

Has anyone ever brought Billman in on these copper discussions? He would know more than I do about possible sources in these cars specifically.

 

I'm neither Birdshot nor consider myself an expert so take my opinion anyway you see fit:

As fas as I've seen the only Cu source in the F20 is either the timing chain idler journal or the crank journals.
The cams run in alu, no doubt.
Birdshot makes a good comment about the layers of the crank journals though.
If you Wiki "white metal" you will find the stuff itself, used for crank bearings, can have up to 3.5% Cu.
The TC idler journal also has some layers I think, the visible outside layer is brass or bronze, no doubt.
I do not know if the OEM water/oil heat exchanger has copper parts, it could be.

Did you change oil brand?
Did you change to another lab?
Anyway the Cu could be from sample taking or the transport container?
Did you put NeverSeize on the drain plug ?

 

Thanks for the replies everyone. I'm not too concerned at this point - but it has my attention nonetheless.

Spitfire: I haven't changed anything with respect to oil (Amsoil Z-Rod 10W30), oil lab (Oil Analyzers) and I never use anything on the drain bolt threads. You mentioned the timing chain tensioner - which has come to my attention due to sporadic/occasional increase in noise (possibly signaling the need to change it out).

There was no evidence of anything out of the ordinary in the oil pan and my Spoon magnetic drain plug was clean.

Birdshot: my sample may have come to your lab - can I discuss the possibility of running a more in depth analysis on the sample offline with you (if it can be done at this point) and what the cost might be?

Thanks again.

 

Did you add any fuel additve during this OCI? If so, check the ingredients. Sometimes these fuel additives have strange ingredients.

IMO, 13ppm is nothing to worry about. On BITOG, some of the experts talk about a stray partice streak that gets stuck in the bearing, causing an uptick in some wear metals. Ths could dislodge some copper underneath the outer bearing layers witout seeing a significant increase in lead or nickel.

 

I mean the timing chain idler gear.
The one where the chain runs on - that drives the scissor gears / cams.
The TCT has no parts that have Cu.