Hi all,

I'm planning to have an oil analysis performed soon. What am I looking for as an indication of failure? Is there anything especially special I should have tested in regards to our engines?

 

See Doug Hillary's earlier posts on his UOA, with details. IIRC, high silicon is a sign of dust and sand getting past the aircleaner, some metals are signs of internal wear, other chemicals are signs of water getting into the oil - gasket problems.
jp 83 Euro S AT 49k

 

Hi,
Tim - if you care to publish your results on here we can discuss them openly
It is wise to ask for a Total Base Number (commonly called TBN) and/or a Total Acid Number (TAN) test which provides an indication of the acidic control reserve left and or the acid build up.
Tell the Lab the amount of topup oil added during the OCI as this has a bearing on the results too

Accurate analysis is important as many variables exist. The Lab will comment on the report and as usual interpretation is always open to error - I have seen many over the years!

John is correct regarding silicon (except if the engine has been opened up when some sealants.gaskets "bleed" silicon) and with his comments on wear metals too
He mentioned my earlier UOAs published on here and these form a very accurate baseline for a 928 engine in good order. I will be posting another UOA very soon (mid Sept) as my car is up for its annual oil change then

I believe that regular UOAs may help to avoid the catasrophic thrust bearing failure that sometimes result from drive line issues

Regards

 

This engine was recently rebuilt (within a few years) though not by me and I am trying to establish a basic knowledge of what I should be seeing as "normal" and otherwise. I'll look through your posts Doug, and I appreciate that you are willing to discuss it once the results are available.

Do you know of any particularly good labs here in the States that could handle this?

 

tHIS SITE has lots of info, and pointer to a lab or two...
http://www.bobistheoilguy.com/whatisoilanalysis.htm
Others have mentioned somebody in US they have used....do a search.
jp 83 Euro S AT 49k

 

Hi,
Tim - John has given you some details and two Labs with a good track record in the US are;

1 - www.blackstone-labs.com
2 - Butler Machinery - call: 701-223-0890 and ask for the Oil Analysis Lab

All the best