Oil Analysis - what does it really mean

[AllThumbs]

When I got my oil analysis back, it appeared good. Problem is they don't give you any reference numbers so you know what is good and what is bad and by how much. Here are the numbers I was concerned about but I don't know if they are out of bounds or by how much. :confused:

Soot - 0.2%, Silicon - 16, Sodium - 65, Potassium - 142, Molybdenum - 11.

Viscosity was listed as 14.1 at 100C and that was listed as a mild variation from normal but they did not say if it was higher than expected or lower.

Wear metals were almost nonexistent. Fuel and water in the lubricant were almost nonexistent.

Any thoughts on this?

[ccc]

I don’t know if this will help you or not but I was an owner operator for ten years and I did an oil analysis every oil change (10,000 miles which was about every month.) I had the work done at the Cummins shop and they kept a file on the truck. They told me the purpose of the oil analysis was to watch the trend, primarily for copper. Apparently the numbers trend on several metals gave them a wear pattern. The motor, a Cummins N14 had 985,000 miles on it when the truck was wrecked and we had never opened the bottom end. Several of my fellow O/O that worked for me had rods and mains replaced when the copper numbers spiked in their oil analysis. I guess the point is, it isn’t much help as a snapshot but good for trend analysis.

[Robyn]

The best use of the oil analysis program is as previously mentioned, to watch for changes that indicate trouble brewing.

If you start a new rig on a program, then you can watch things and see whats happening over time.

On an engine that you have zero past history of, the tests can help isolate problems.

Examples

Heavy soot numbers will indicate bad injectors (over fueling)

Fuel contamination (leaking pump seals in a 6.2/6.5) or in other engines an issue with injectors that are under the valve covers (or internal fuel lines)

Water/glycol contamination will indicate a cracked head/block, head gasket or with the 6.2/6.5 a possible waterpump back plate.

The metal levels can be useful to indicate bearings that are wearing.

Ths bearing/metal levels are more useful when you have long term trends that show changes in the base readings.

I have only used oil tests a couple of times and these were done to test for glycol contamination.


Missy

[AllThumbs]

Thanks for the help. I did the analysis to get a baseline on this engine. I had concerns because of losing antifreeze. It did appear to dispel any thought that the antifreeze was getting into the engine. They certified the oil for continued use which made me feel pretty good. My real concern was that they throw a bunch of numbers at you without explaining what they mean. Any spikes in numbers from here on out will be an alarm bell.:eek: