Oil Analysis Results

Disclaimer: I am not a professional mechanic, so my conclusions may be completely sophomoric. But that is why I am asking for help .


So i just got the results of the engine oil analysis of a 5 or 8 year old genset with 58 hrs on it. From what I can infer from the analysis, it appears that the engine oil has been contaminated with both sea water and antifreeze. Is that what the analysis is showing?? I'm miffed that this is the result of an engine with only 58 hrs. I can only think that if both seawater and glycol are present in a low hour motor, the head gasket has been compromised somehow and water has passed through the HX or exhaust manifold. My current plan to proceed is to have the oil changed and run the generator for 10 hrs and retest. Is this a good place to start, or should a mechanic be breaking down more of the motor at this point?

I think you misread the analysis. It says no glycol found. That sounds to me like the the sodium didn't come from the coolant. I might inspect the raw water pump if it is a direct drive, but most have a drain hole between the oil and water seals to prevent oil contamination from the water pump side. Salt (sodium) can enter through damp air in the intake. The high iron is probably from lack of use. Is the unit in the engine room or lazarette?

I would change the oil and filter and run it for 20 hours under load and then retest. Based on those tests I would repeat or wait till 100 hours.

You have to use it more!

Ted

You definitely have sea water salts in your oil. The reported sodium to potassium ratio is close to what is found in normal sea water. No glycol means no antifreeze. The high Fe is probably due to sea water corrosion.

So drain the oil, replace and run for a few minutes and drain and replace again since each time you easily leave 10% behind which contaminates the next batch.

The sea water could be coming from a main heat exchanger leak, but usually the pressure is higher on the oil side. The more likely cause is sea water backing up due to a bad exhaust system design. Join boatdiesel and read about hundreds of examples of this.

You could try running for a while particularly if you get the sodium down to 1/100 of its current value which will be close to normal. Then watch for water vapor(steam) or condensate droplets from the breather and oil level rising. If you see any of those stop and investigate the exhaust system and heat exchanger.

David

DavidM said:

You definitely have sea water salts in your oil. The reported sodium to potassium ratio is close to what is found in normal sea water. No glycol means no antifreeze.
David

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Ok lets try it.



From https://web.stanford.edu/group/Urchin/mineral.html


I get NA 10561PPM and K 380PPM in sewater for a ratio of 28PPM NA to 1 PPM K.


And from the sample analysis I get 1868(mystery units) Na and 75(mystery units) K for a ratio of 24 to one. So if the units in the sample are PPM then it looks like you both are correct and we only have seawater.



I am also told the raw water pump is leaking. So it appears that you both are hopefully correct , and we may simply have raw water intrusion through the raw water pump. Hopefully not the exhaust.


To be sure that there is no seawater intrusion through the exhaust manifold, would water intrusion into the exhaust manifold be obvious once i pulled the hose off the exhaust elbow?

O C Diver said:

I think you misread the analysis. It says no glycol found. That sounds to me like the the sodium didn't come from the coolant. I might inspect the raw water pump if it is a direct drive, but most have a drain hole between the oil and water seals to prevent oil contamination from the water pump side. Salt (sodium) can enter through damp air in the intake. The high iron is probably from lack of use. Is the unit in the engine room or lazarette?

I would change the oil and filter and run it for 20 hours under load and then retest. Based on those tests I would repeat or wait till 100 hours.

You have to use it more!

Ted

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I was concerned about Potassium being present from the antifreeze.


The genset is in the engine room.


Can anyone comment on how bad the amount of iron is in the sample on a scale of 1-10? I was told by a mechanic it is way out of line on for break-in on a genset with 58 hours.

You probably have an intake silencer that sort of resembles an air filter. I would open it (if possible) or remove it to look for salt residue. If the water pump is leaking, depending on where the water is being thrown or the heat level inside the sound shield, the water may be vaporizing and getting sucked into the engine intake. That's why I would look for salt residue there.

Or, you could fire up the generator and see where the water is going or being thrown.

Ted

bligh said:

I was concerned about Potassium being present from the antifreeze.


The genset is in the engine room.


Can anyone comment on how bad the amount of iron is in the sample on a scale of 1-10? I was told by a mechanic it is way out of line on for break-in on a genset with 58 hours.

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An anecdotal story about rust in the engine:
I did the Great Loop in 2017. My pickup with the Cummins diesel 6BT sat for over 7 months without being run. Iron went up 50% sitting in my air conditioned garage with a 50% relative humidity, at the next oil change.

Your iron number is bad, but the aluminum (piston) is surprisingly good. Short of rebuilding the engine, I don't think there's much else you can do. I'm OCD guy with an obsession for preventive maintenance. If it were mine, I'd fix the water pump leak, maybe service the heat exchanger and replace the anode, change the antifreeze, change the oil and filter, and run it for 20 hours. Check the oil maybe every few hours to make sure it isn't using any. Then do another oil analysis. The rust levels aren't going away with the first, second or third change. It will take time to get back to a base line level.

Ted

bligh said:

Can anyone comment on how bad the amount of iron is in the sample on a scale of 1-10? I was told by a mechanic it is way out of line on for break-in on a genset with 58 hours.

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This has nothing to do with break in. This has to do with a 5 or 8 year old generator sitting with almost no hours on it and humid air getting inside the cylinders and crankcase.

BTW, do you know what the engine oil was? Was it break in oil with a different additive package designed to help seat the rings?

Ted

What is the make and model of the generator, please?

What is the service history? Please be specific about what was done, date, and hours.

When was it new/placed into service?

Looks like seawater to me too. What kind of gennie, and is the sea water pump leaking? SWP will do it if gear driven.

It sounds like the interpretation is saying even though there no detection of coolant/water, it may be entering the combustion but is burned off. So, he's not ruling it out. It is confusing. Maybe a cover their ass kind of statement. However, the deterioration of the English language in the USA is so prevalent... I'd ask for clarification from the analysis lab. Sorry to hear you're finding this type of issue. Hope it works out, it's such a beautiful boat.

It is a mastevolt 12.5 kW generator with 58 hrs and no service history. I guess it to be between 5 and 8 years old.

IRENE said:

What is the make and model of the generator, please?

What is the service history? Please be specific about what was done, date, and hours.

When was it new/placed into service?

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Swfla said:

It sounds like the interpretation is saying even though there no detection of coolant/water, it may be entering the combustion but is burned off. So, he's not ruling it out. It is confusing. Maybe a cover their ass kind of statement. However, the deterioration of the English language in the USA is so prevalent... I'd ask for clarification from the analysis lab. Sorry to hear you're finding this type of issue. Hope it works out, it's such a beautiful boat.

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Maybe burned off. During sea trial we ran it for almost 4 hrs. Im not sure what the oil temperature would be.

And the idiot light was on. I forgot it had one.

O C Diver said:

BTW, do you know what the engine oil was? Was it break in oil with a different additive package designed to help seat the rings?

Ted

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No idea.

I would definitely run the leak or pressure test previously suggested before putting it back in service. Would not want to do any damage due to continued leaking. Would also share that oil analysis with the engine builder and get a quote for an engine tear down, inspection or a swap. It's possible a little preventative action now could extend it's remaining useful life several years. The iron is troubling - crank and cylinder walls might just need honing or polishing now - preventing scoring over the next hundred hours.

I think you are reading the analysis correctly - exactly what it means and what to do about it probably needs a few more data points. IMHO

I personally would drain/suck out the oil into a clean container and inspect it, cut open filter and pull apart pleats and inspect. If the oil does not resemble oil then its time for some thorough troubleshooting. If it looks semi normal I would service it back to full, change filter and run it for 10 hours or so. Stopping and starting several times to let it completely cool back down. Resample and change oil and filter again...wait for sample results. If sample is ok or MUCH improved then do a resample and oil filter change with an increase in operating time...maybe 30-40 and do it again.

During these run periods I would check for secondary issues. Overheating, loss of coolant, exhaust/water flows, oil pressure, exhaust smoking after subsequent restarts etc.

I think the probability is that you can get that gen back on track. An oil sample after sitting so long is nearly worthless. Well..not quite worthless but I would never expect a sample to come back good after such a length of time. Just my opinion.

I would definately do the cooling system pressure test and see what that shows.
How was the sample taken? During an oil change or just sucked up out of the dipstick tube? From the top , middle, or bottom of the sump?
Was it hot?
I ask because I once had extremely high iron in a sample I took from a velvet drive tranny. Was told the iron was so high the tranny was shot. Upon disassembly I found a magnet epoxied to the bottom of the sump (not shown in the repair manual). The bearings and gears were fine upon inspection.
My assumption was that I took the sample from next to the magnet resulting in high iron. (duh)

The moral is that there is more to a sample than just the analysis.

There must be more to your report. Usually there is a column that shows what should be "typical".

Rusty cylinders from lack of use would account for iron.

What's with the calcium number?

Olebird and I agree about the cooling system pressure test. It should be quick, simple and inexpensive. It'll also clarify the analysis statement about glycol possibly burning off. It's a shame that they put in a new penny, ran it enough to do a "break in" and then neglected it. Maybe that's what happened to the first genset too. Reasonable boat, engine use but no need to run genset. Living in FL west coast, for 20 years, lots of wealthy folks with houses/comdos that get used 2 months a year and boats that sit 10 months as well. My job was to clean, check fluids and run gas engines at dock or diesels once at speed/load for an hour. A bit off topic but the areas where owners had issues were bottom cleaning/painting/zincs schedule, exhaust risers rusting internally without a fresh flush system and mildew in cabins due to lack of dehumidifying measures. Almost always from boaters from a freshwater midwest environment. They learned pretty quick.

I had the same problem. Took the engine apart replaced gaskets the whole bit. Found nothing conclusive. Next year, same results. Looking at pics I took while apart, I noticed more corrosion on the port closet to the exhaust and less each port going away from the exhaust. Figured the only way that can happen is its backing up when not running and underway. I installed a shutoff for the raw water intake and diligent about not having it open when not, in use, while underway. 3 years now and each year the wear metals are basically halving each year. Almost at normal now. Can't say thats your problem but I have seen many drowned gens and suspect thats the reason