Oil sample back on 3116 with a yellow/"monitor" rating

[tc410]

Yes, oil coolers are COOLANT cooled (mounted on the engine) and NOT RAW WATER cooled......

Dude..... Why are you YELLING??? Fwiw the oil coolers on my Cummins are RAW WATER COOLED....

 

[ttmott]

I have a bit of an update with this. I had a long talk today with the lab the processed the oil. In summary, the tech said that Na was a bit abnormal, but not all that uncommon. THat's why they suggest simply monitoring it, which means changing the oil, running it 25 hours, and then retesting. I was told a common cause for higher Na # is salt water condensation. During these colder mornings, salt water will condense on the inside of the block. When you start the engines, the water burns off and you're left with the salt. The tech said it's not something that they'd be all that concerned with. But I'm the one paying the check, so it's a concern to me. I was also told that once the Na is detected at a PPM higher than 25, they automatically look for antifreeze or water in the oil. Their tests showed neither.


So, where does that leave me? Well, tomorrow I am heading back to the boat and I will take more oil samples myself. I'm going to take one sample on the suspect engine cold, and then 2 more samples (one on each engine) once the engines are warmed up and have been under load for 10 minutes. Once I get the results back from those 3 tests it will be decision time.

Stay tuned.

Good call. Assume you have a sample extraction tool and the appropriate sample vials. Very important to be sanitary with clean tubes and vials for each sample taken; the samples are analyzed to the parts per million so you can see that it isn't hard to compromise the results. Like I was saying in an earlier statement; in these engines there would be a significant fault that would be detected in other observations if salt water from the raw water system was in the oil. There is trace sodium in ethylene glycol (ELC) and if the ELC was getting in the oil there would also be other chemistry like potassium detected as your tech. alluded.
BTW - the aftercooler is jacketed with ELC in the 3116 and with raw water in the 3126; an important difference FYI.
And as an edit - see if they can give you a value for soot; this is a looking-glass on how the engine is loaded.

I wouldn't walk away from a good boat that you really liked because of a contaminated sample or questionable observation - as a statesman once said; "trust but verify".

 

[becnme]

Before you waste your time taking more samples listen to what Frank said about your other readings that are higher. Your iron is up on that engine too so it is not sample contamination. What ever has caused this, salt water intrusion, condensation or what ever has caused more wear on that engine. This is why oil samples are taken to alert you too a potential problem. You need a Cat expert to lead you in the direction you need to go to find the problem even if it is a simple oil change.
This would not be a deal breaker for me but I would like to know it is repaired before purchase.

 

[JeffM]

I was told a common cause for higher Na # is salt water condensation. During these colder mornings, salt water will condense on the inside of the block. When you start the engines, the water burns off and you're left with the salt.

This is liberal/Democrat science. When water evaporates, contaminants (like Na) are left in the originating liquid. When it condenses, it condenses as H2O -- think distilled water. No Na -- or other contaminants -- would likely be present in the condensate unless they were present on the surface the water condensed on.

 

[trit21]

I don't think, again IMO, that the values for iron, al, and copper are high enough to warranty any issue. Thing wear and if the boat was not run for a while I would expect numbers to be slightly higher but stabilize. Oil test without historical data is useless. Are these values a one time thing or has it been going on for some time and most importantly, are the numbers increasing, decreasing, and will that trend continue. One off oil samples are good to detect coolant, fuel and sodium in the oil, that is about it unless those number for iron etc are off the chart.

I haven't seen the number for blow by and if that was conducted correctly. Maybe I missed it but blow by give you a real good indication of the internals of an engine.

How do these engine start cold? When you hit the key/switch do they fire right up or take a long time to start. Another indication of internals of a diesel engine.

TC410, wasn't yelling was emphasizing as it seems some missed coolant vs raw in my first post.

 

[fwebster]

I admit that I did miss the part of the discussion re: sea water vs. jacket cooled oil coolers. Just keep in mind that that we are talking about Cat 3116's not some other Cat engine and not some other brand.


I don't think you can just blow off the wear metals result in the oil sample with a generalization. Consider that the port and stbd engine results posted were from engines in the same boat. The stbd engine has 9 X more copper and 3 X more iron than the port engine. I think whatever environmental conditions affect one engine would also affect the other, so I'm not buying the notion that condensation caused the high sodium levels in only the stud engine. And, I would want a better answer than we've seen thus far for the high wear metals in one but not the other engine.

I would also like to add that the real value of oil sampling is to enable you to spot developing unhealthy trends in your engine health. As a repurchase diagnostic tool they aren't as valueable but they will point you to areas where a competent diagnosis by a qualified engine technical is needed.....as in this one.