Oil analysis found %0.10 antifreeze in oil - CAT 3116

I sent my oil samples off to Blackstone and it came back with 51 ppm of sodium in the oil. The previous three years I had zero.

The report suggested that I may have a coolant leak somewhere and that there was also 0.10 percent of antifreeze noted in the sample.

To the best of my knowledge, there has been no additional smoking or any coolant use.

I'm headed to the Bahamas in two weeks and the run will take me about 100 hours to I plan to pull an new sample and check again after that.

Any thoughts on where to start looking?

I would defiantly get my Cat man to find the problem before I went on a 100 hr. Trip. Could be something simple or could be bad, Head gasket, Cracked head or Block. This is something for the professionals.

That's definitely not good and definitely not going to get better. Personally I would get it fixed before I'd go. Not sure if you would want to have it fixed in the Bahamas.

Before you get excited here, look at the oil analysis again and look for "glycohol". If you have a coolant leak, and antifessze is in the oil, then the oil analysis will also show some level of gylcohol on the sample report.

That may rule out some of the more serious/expensive causes for sodium in the oil like head gasket leaks, but if glycohol is present, then I would call Caterpillar.

Absent glycohol, one primary cause of sodium is ingesting seawater thru the air intakes. If there any sign of a hose leak or water on the intake side of the engine after a run?

Another cause could be the fuel cooler, but I suspect you would see white smoke in the exhaust if there were the cause.

Unless you know somebody it may be difficult to get a Cat mechanic on the boat before you leave.

Good luck with it..........fingers crossed!

It was not tested for glycol.

I don't know how close you are to a Caterpillar store, but their SOS fluid testing kit does check for gylcohol and is designed to maintain and monitor Cat engines. Their reports are pretty specific for Cat products and not generalized. THe kit is about 1/2 the cost of Blackstone and includes prepaid mailer, sample bottle, and tube to draw the sample. I got my last ones from Thompson Cat in Panama city and they were $14 ea, for oil.....coolant is a bit higher.

If might be helpful to get a Cat kit and sample that one engine to hellp you narrow down the issue.

Thanks Frank. I have a Ring power near me that does on road stuff so I would figure that I could get the kit there?

I have gotten a few different opinions about the sudden change and honestly don't know to be worried or wait and see what 50 hours brings.

I'm thinking about renting a coolant pressure tester to start off with. Thoughts?

On a side note, I did have a pretty good raw water leak from my generator hose this past year. It wound up killing the back end of my generator. That hose system is about 1.5 ft from the port engine.

Sodium as in raw water contamination as opposed to antifreeze?
I would follow Frank’s advice and get it tested. Worrying about it on a long trip may ruin the trip for you, and may be unnecessary.
If you test and all is fine you have peace of mind. If you test and there is a problem then at least you’ll know it before embarking on a long trip.
The fact that you haven’t noticed any coolant loss or use is probably a good sign, but it would be nice to know for sure. Plus, a blown head gasket or cracked head usually comes after an overheating episode and that would result in antifreeze contamination, not raw water.
If there is raw water contamination I would be more suspect of a cooler like Frank mentioned.
Either way, I would do an oil change before you make the long trip.

The Caterpillar SOS kit is the same for marine or off road equipment. I buy my Cat parts in Nashville because that is an earth moving equipment store. The 3116 was very popular in the #12 road grader and in several large trucks like the GM TopKick. I have had to get the Nashville store to order marina parts but have never waited more than 2 days....filters, fluids, SOS kits are all in stock. Ring was/is the Cat distributor for Sea Ray so I am sure they would have what you need.

Since you know you have had water spraying under pressure in the engine room, I'd be inclined to get an SOS test kit and have a sample run to check for sodium and glycohol After your oil change. Depending upon which lab your sample goes to.......and I think Ring has one.....the form may show glycohol or it may show anti-Freeze, but they are the same thing. Before pulling the sample, run the boat 1-2 hours at operating temperature under load before pulling the SOS sample so you know you have boiled off all the moisture that may be in the crankcase. You will get the results from Cat in about 5 days.........

Thanks all.

I have fresh oil in the engine which is how I got the oil analysi on the old oil.

Frank, how long do you think I would need to run the engine to get a good sample for the SOS kit? There is zero time on the oil right now.

I don't know if Frank missed it, but your original post says that .1% antifreeze (glycohol) was detected - so they did test for it.....

For typical monitoring, you need 25 to 50 hours on the oil to get a representitive sample. Your case is different......you have already identified high sodium, you have a trip planned that you need to make a go/no-go decision on, and you need to know if you need to get a diesel mechanic involved and at what point.

The presence of antifreeze (glycohol) in the engine oil tells you a lot as far as where to go from here. My thought is to run the engine at operating temperature and loads long enough to burn off any residual moisture in the crankcase....a minumum od 2-3 hours under load at normal operating temps ----the longer the better. Then, when you get back to the dock, pull your oil sample. Pull the sample from about 1/2 the depth of the oil in the pan. Mark a spot on the plastic tube 12" above the bottom of the tube and stick the tube into the dipstick tube on the engine until the mark on the plastic tube is even with the top of the dipstick tube. Do not use the reverso pump to pump out oil for the sample....that oil is contaminated by the other engine and generator as well as new oil you may have pumped into the engines with the reverso. Cat has a pump for pulling samples- about $35 or you can use a large syringe that fits inside the plastic tube. The sample jar only needs to be 1/2 to 2/3'rds full.

Results wise, if you had seawater ingested thru the intake, you can expect to see some residual sodium in the oil sample, but if ingesting spray from a generator leak was the cause, I would expect the sodium level to be less than the Blackstone sample. If there is no glycohol in the oil, that almost certainly rules out a breach of the cooling system into the engine thru expensive places like a head gasket.

A decreasing level of sodium and no glycohol in the oil just about puts me in the "Take the trip but take it easy and keep an eye on things" column.

If there is antifreeze in the oil along with high sodium, I would want to rule out a leaky head gasket before running the 100 hours you anticiate your trip requiring. Facing a head and replacing a head gasket is an $1600-$2000 repair, depending upon how hard it is to get the head off the engine in your particular boat. Let it go and you could end up with a cracked or warped head which changes to financial hit to a minimum of $6K for just the remanned head.

Sorry you are facing this, but good luck with it.......

Thanks Frank. I'll run the boat tomorrow and see what I can come up with. I don't think I have enough time to get the SOS kit this weekend but I can pull a sample and get the kit next week.

For the trip I'm taking, I won't be running any faster than 8kts the entire time so unless something catastrophic is occurring, I shouldn't see any overheating?

Not overheating, but you need to watch the coolant level. You are probably losing a microscopic amount, but if it gets worse, you won't get any warning, and about the last thing you want to do to a diesel is to run it hot, so be careful.

Today’s update -

I got into the engine room and look close at the coolant overflow bottle. It was pretty low and that initially had me concerned. I then realized that I have never added coolant to this boat in the four years that I have owned it.

I went ahead and brought the overflow bottle up to the cool setting.

I borrowed a pressure testing unit and put 10 psi on the bottle.

It held 10 psi Consistently with no drop.

Related to that, when the gauge plug pops out of the tank, 10 psi of coolant gets aerosoled nicely all over the inside of the boat.

When was the last time the aftercooler was removed, cleaned and pressure tested? I believe that the aftercooler on your motor is antifreeze cooled. A small leak there would cause the engine to ingest antifreeze.

I'm not sure. I know I have never done it.

Well the plot thickens.

The oil analysis came back for my starboard engine. It too showed a significant increase in sodium.

Both engines now show an increase from approximately 4 ppm of sodium to 300 and 500 ppm of sodium.

There only two things that these engines have in common. First is the airspace did they occupy. Second is the oil transfer pump.

I’m beginning to seriously think that both samples were tainted at the transfer pump somehow.

Did you pull the samples at the oil change pump as you pumped out the old oil? If so, suggest you re-read the 2nd paragraph of post #12.

Old oil from both engines and the generator could easily contaminate the oil in the oil change pump. Also, take a look at the coolant in the generator. I have a Westerbeke 8.0BTD and the heat exchanger failed at about 12 years of service. Seawater entered the cooling system and was in the Westerbeke's water jacket. We caught it and replaced the heat exchanger before any damage was done, but that would sure screw up an oil analysis.

Unfortunately when I did the oil change I did used a sample out of the pump.

Normally I poured straight from the filter into the collection container.

I have yet to run the engine since I sent this oil out for analysis so I will rerun in the near future and see what changes.

That’s an interesting thought about the generator. My Westy smokes a little bit and thinking about it now it could very well be some antifreeze.