Coolant in Oil

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seasalt007

Guru
Joined
Jun 27, 2014
Messages
628
Location
U.S.
Vessel Name
Aweigh
Vessel Make
Nordic Tug 42
I just got the oil analysis results for a boat I was purchasing. The oil sample on one engine shows a high level of coolant.

This may be a deal killer for me since there are several ways for it to get there and none are good.

Should I run?
 
Should I run?

Assuming the sample is accurate, tell the owner the deal will not move forward until verifiable reasons are known and fixes made. But if the boat is one of many, look at the alternatives.

BTW what are engine age, make and vessel?
 
Yes, coolant in the oil is bad and the fix is often expensive. But be aware that Blackstone for one, doesn't know the difference between high sodium caused by coolant or high sodium caused by salt water. They do not measure glycol. They infer coolant from the sodium level and on marine engines it is just as likely to be due to salt water intrusion. Not that that isn't any better ;-).


David
 
Is the oil milky looking, it takes very little coolant in oil to turn it milky. If it is, then you definitely have a problem. Depending on engine, it could be things like liner seals, head gasket, oil cooler etc.
 
Test again through another lab .... they are not all created equal.
I've seen a number of reports on the same fluid with significant differences.
 
I just got the oil analysis results for a boat I was purchasing. The oil sample on one engine shows a high level of coolant.

This may be a deal killer for me since there are several ways for it to get there and none are good.

Should I run?


I had the same problem during purchase of our boat last year but the Lab here ( Wear Check ) could not determine the amount of glycol in the oil. I was told that because the way glycol mixes / interacts with oil, it is impossible to determine how much glycol is present, they can only determine Yes or No for glycol. To explain ...... their ( the lab's ) baseline was .06 ( whatever that means ) ... so @ .0599 or less is NO and @ .061 and more is Yes. Could be a contaminated sample, oil cooler leak, or on the outside ... a head gasket ... ? so I was told. In my case, I wrote it off as a non - issue at this time, as I am not losing coolant, not gaining oil, there is nothing coming out of the exhaust etc. and there is no visible contamination of oil or coolant.

Good luck with this one .... FB
 
I had the same problem during purchase of our boat last year but the Lab here ( Wear Check ) could not determine the amount of glycol in the oil. I was told that because the way glycol mixes / interacts with oil, it is impossible to determine how much glycol is present, they can only determine Yes or No for glycol. To explain ...... their ( the lab's ) baseline was .06 ( whatever that means ) ... so @ .0599 or less is NO and @ .061 and more is Yes. Could be a contaminated sample, oil cooler leak, or on the outside ... a head gasket ... ? so I was told. In my case, I wrote it off as a non - issue at this time, as I am not losing coolant, not gaining oil, there is nothing coming out of the exhaust etc. and there is no visible contamination of oil or coolant.

Good luck with this one .... FB

To add to my post, I negotiated a price reduction for repair of the worst case scenario ( Oil Cooler and - or Head Gasket )
 
Was a deal breaker. 2006 Cummins QSC 8.3, 500 hp, in a downeast style boat. Factory certified Cummins tech said only way to find out what caused the problem is to tear into the engine starting with removing the head.
 
Yea, I'd probably recommend letting that one go unless they actually fix it.

Too many sneaky places for coolant to get in oil. Could be porosity in a casting and no one will find that.

And a Downeast with two engines?? Only one engine in a DE!!!!
 
Yea, I'd probably recommend letting that one go unless they actually fix it.

Too many sneaky places for coolant to get in oil. Could be porosity in a casting and no one will find that.

And a Downeast with two engines?? Only one engine in a DE!!!!

42' DE needs a couple.
 

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