Monitoring Oil Oxidation Value - OAI

[buster]

Here is OAI's response on this figure for future reference. Don't just go by good TBN reserves.

"Thank you for contacting Oil Analyzers with your question.

With the flagging system we have in place currently, Oxidation will be flagged severe or critical if the level increases 27 over the baseline starting point. By default, the report would come back and recommend changing the oil if not done so at time of sampling. In your scenario, if wear metals, viscosity, and all other properties are fine, I suppose the oil would technically be ok for continued use. However, increases in Oxidation like that would mean the oil is being exposed to high temperatures and things could change rapidly if not sampled/monitored on a frequent basis. If the oil is oxidizing, in most cases, you will see an increase in viscosity. Total Base Number will also decrease as heat will shorten the life of the oil.

If that type of situation ever did occur, I would be hesitant to continue using the oil, knowing that the Oxidation level is high. Once the oil starts to breakdown, the snowball effect begins, with varnish starting to form, oil coking, and eventually sludge buildup.

If you have any other questions, feel free to contact us.

Thanks,
Ryan Lawrey, MLA I, OMA I
Senior Analyst – Oil Analysis"

 

[fantastic]

Yes, It needs to be stated & appreciate the post. Here's their guidelines that reflect the 27 as "Critical" along w/other good information I've used to compare w/my own UOA's.

https://www.oaitesting.com/reading-reports.aspx

 

[buster]

Yes, It needs to be stated & appreciate the post. Here's their guidelines that reflect the 27 as "Critical" along w/other good information I've used to compare w/my own UOA's.

https://www.oaitesting.com/reading-reports.aspx

Thanks this is good too .

So basically once your 20pts above baseline it’s likely time to change the oil.

 

[fantastic]

Thanks this is good too .

So basically once your 20pts above baseline it’s likely time to change the oil.

Agreed

 

[Gene K]

20 is what I used when I was doing 30,000+ mi OCI with heavy diesels on conventional back in the 90s. Went a million miles on some of them. Headgaskets going before a million miles was usually the limiting factor. Only made sense to overhaul then, but some of the pistons and liners really looked like they could be put back and and run another million.

 

[Jetronic]

Thanks this is good too .

So basically once your 20pts above baseline it’s likely time to change the oil.

But that implies you know the baseline, which could be as high as 100 (some Red Line products).

 

[Glenda W.]

Thanks!! Great info

 

[buster]

HPL, Amsoil and RL don't leave varnish behind even with some oxidation possibly because of the solvency of the group V. Notice how clean the engines look all 3 of those oils we you see tear downs.