'04 Subaru WRX STi w/ High Copper UOA

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Just received my first UOA from Blackstone for my '04 Subaru STi. The engine has about 62k miles. Penzoil Platinum 5w30 was run for about 3200 miles with a Mobil 1 filter. The report came back showing high copper. Any ideas what could be the cause? Some additional background: 1) A couple weeks before taking the oil sample it was discovered that the turbo wastegate housing was severely cracked (hairline crack is common, this one was much worse than usual). 2) A metal fragment about the size and shape of a gear tooth was discovered in the banjo bolt fitting for the Turbo oil line. The fragment was about 1/4" square and flat. Very likely this caused some reduced oil flow to the turbo. 3) I am getting excessive blow by with oil pooling in the throttle body. PCV valve has never been changed (will be done shortly). Blow by is common in the 2.5l subaru engines but the oil accumulation was excessive. New turbo will be ordered shortly. Just wondering if there is any way to isolate the source of the high copper. Thanks for any input you can provide. Additionally, I have already switched to Rotella Synthetic 5w40 oil and a Purolator oil filter. [IMG]http://img170.imageshack.us/img1 [img][URL=http://img170.imageshack.us/i/blackstone07242009.jpg/][/img]
 
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What is the bearing material inside the turbo? Could be theturbo bearings as a result of the reduced flow (potential reduced flow anyway), it could also be particle streak. I would do another UOA at the end of the next OCI before coming to any conclusions. Wow, almost missed the sodium? Those additive levels don't really look like PP. Did you do any work to the engine lately that might result in an increased sodium level (new gaskets via a gasket maker?)
 
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PP isnt a bad oil IMO, but as en energy conserving oil, its not robust enough for a turbo Subaru. The Rotella 5w40 should perform much better. I'm betting on much better results from your next UOA.
 
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 Originally Posted By: RonJitsu
PP isnt a bad oil IMO, but as en energy conserving oil, its not robust enough for a turbo Subaru. The Rotella 5w40 should perform much better. I'm betting on much better results from your next UOA.
How come this add pack doesn't look like PP? Whats the date code on this, perhaps this is the super old formulation.
 
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Stook, Here's a UOA from my 08 Subaru Legacy GT 5-speed running 3600 miles with PP 5w30. http://www.bobistheoilguy.com/forums/ubb...rue#Post1426737 Notice the prettymuch identical copper spike as a function of parts per million / 1000 miles? The discussion back then, and what I'm at least prone to believing, is that the copper is actually from the oil cooler oxidizing. I really have no clear idea though why some subarus pretty much never show this, and others have an occasional spike of about 30ppm of copper in a sub-4000 mile run. I am not 100% what the turbo bearings are made of, but the common consensus (which may or may not be accurate) is that a spike in silver is evidence of turbo bearing wear. By the way, one random thing, you have 3 PPM of Manganese. You almost never see more than 1-2 PPM of Manganese unless a car is severely fuel diluted, but you have 3 PPM and no real evidence of strong fuel dilution....your viscosity and flashpoint is normal. Just odd to me, though well within a level of statistical noise. Joe
 
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That's NOT PP in your analysis - PP has BOTH Moly and Boron. That looks like Valvoline Synpower - it uses sodium in its add-pack, and no moly or Boron. You might want to check with the lab that they didn't get your sample mixed-up with someone else's....but that is definetly not a PP analysis you posted.
 
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 Originally Posted By: addyguy
That's NOT PP in your analysis - PP has BOTH Moly and Boron. That looks like Valvoline Synpower - it uses sodium in its add-pack, and no moly or Boron. You might want to check with the lab that they didn't get your sample mixed-up with someone else's....but that is definetly not a PP analysis you posted.
Yeah, I didn't want to claim that because I've seen PP 5w30 show alot of different values for zinc, phosphorous, and calcium...but I don't think I've ever seen PP 5w30 show that much sodium.
 
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 Originally Posted By: stook2001
.......................................................................................... 2) A metal fragment about the size and shape of a gear tooth was discovered in the banjo bolt fitting for the Turbo oil line. The fragment was about 1/4" square and flat. Very likely this caused some reduced oil flow to the turbo. 3) I am getting excessive blow by with oil pooling in the throttle body. ........
The metal fragment is possibly a piece from the ring land?
 

stook2001

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A couple of quick updates (thank you for the great feedback). After further review of my waste oil containers it is possible that I was mixed up and that I was actually running the Valvoline Synpower in the Subaru and running the Penzoil Platinum in my other vehicle. Apologies for the confusion - I'd done original oil change so long ago that I may have just mixed up the details. Regarding the metal fragment, I'm wondering how the ringland piece would have gotten to the banjo bolt connection at the turbo. I'd assumed it was a more localized piece from somewhere on the line. I'll do some research - I don't even know what the ringland looks like. Also, I realize that it is not necessarily indicative but I did a compression test right before I changed the oil and collected the sample. The compression was perfect in all cylinders. As I recall the more definitive test for ringland issues is the leak down test but I'll need to do some more research into that. Again, thanks for the great feedback.
 

abs

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Hi stook2001 - Does the STi use Sodium filled valves? If so, could this be part of the source of the high levels of sodium? Interesting idea put out that the bit of metal found could be from a broken ring . . . most pistons have multiple rings on them for things like oil control and compression. I suppose it could be possible to have a damaged oil control ring yet still have a good compression ring? Andrew
 
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