High level of metal found during 911 C4S oil service

[lortonesr]

I recently had my ‘09 911 C4S serviced (21,400 miles) and was told the tech found abnormal levels of metal in the oil. A sample was sent to Blackstone Labs who reported aluminum partials were 3 times normal and silicone was twice normal. The report went on to say this could be “piston scuffing”. The car has been serviced annually by Porsche technicians — with never a mention of this possible problem in the past. I’ve also been told that the 997.2 engines are quite bulletproof. A final suggestion was to drive the car another 1-2,000 miles and have another oil test or consider looking in the engine cylinders with a bore scope.

Anyone have a similar experience OR recommendations about what to do? If the the cylinders are scored, it sounds like and expensive engine re-build to me. Thanks in advance for any advice or recommendations.

Lortone

[Tom_N]

Not immune to scuffing unfortunately. I too was surprised to read that the 9A1/MA1 blocks do score in the latest Total 911 issue. (For instance see https://medium.com/@lnengineering/cylin ... b051e95ddc). I suppose a bore-scoping by a competent mechanic is the way to be sure.

[blueline]

I would tend to follow the recommendations about waiting and doing a second or even a third test. Oil samples need to be collected in a very specific way to make sure no outside or unrelated contamination. Labs can make mistakes too, so a follow-up might show everything to be normal.

Just a suggestion, but maybe try a different lab too. There are a couple, one of which is highly regarded - LN Engineering.
https://lnengineering.com/products/spee ... lysis.html

I found another one that I know nothing about but it looks promising nevertheless:
https://www.oaitesting.com/

PS - If in doubt, order a kit and take the sample yourself or ask to be present when the next oil sample is taken just to be sure it's done by the book. (ie: exactly as the oil testing service specifies.)