[waterant]

Hi guys,

I just got oil report from my Westerbeke W21 back and there are 7% of coolant detected in there. Was 0% for previous two years since i got my new old boat.
This season i changed coolant pump and injectors. Does not look like this would affect any seals because coolant pump is driven by pulley. I had to remove sea water pump to change impeller but report said oil has coolant, not water.

As I understand, coolant is pumped through the cylinder block, cylinder head and heat exchanger. Do you know what would be the most likely point of entry and how to fix it?

Thank you,

Anton

 

[Capt Len]

Consider a deteriorating head gasket weeping coolant into oil passage. Check engine zincs? If pump is completely separate and no oil cooler, what's left.?

 

[Missingyou]

Likely a head gasket as Capt Len suggests. Also a cracked block is another possibility if it was not winterized properly. See if you can find someone with a Bore Scope to take a peak into the cylinders too. If the head gasket is leaking it's possible it's leaking into a cylinder.

 

[waterant]

Thank you. I'll check head gasket and for cracked block (hopefully this is not it).
this got me to do some research about using synthetic oil in older diesels and looks like this is bad idea and can lead to problems with gaskets. i was putting expensive synthetic in for the last 3 years and this season kept it till the end of the season with 180 hours on it, thinking it's good oil and I do not need to change it every 100 hours. big mistake.

thanks again for your advise.

 

[dabnis]

Thank you. I'll check head gasket and for cracked block (hopefully this is not it).
this got me to do some research about using synthetic oil in older diesels and looks like this is bad idea and can lead to problems with gaskets. i was putting expensive synthetic in for the last 3 years and this season kept it till the end of the season with 180 hours on it, thinking it's good oil and I do not need to change it every 100 hours. big mistake.

thanks again for your advise.

If I am reading this correctly, coolant is leaking into the lube oil? Not sure synthetic oil would cause this? However, switching back to petroleum oil & re-testing it would be easy. If the head gasket was bad, blow by from combustion could back up into the coolant or coolant could leak into the cylinders, causing white smoke at startup.

If the water pump body is recessed or "integral" to the inside of the block, a bad seal might cause coolant to leak past, ending up in the pan? You mentioned you changed it this year? Let us know what you find.

Paul T

 

[MarkSF]

Thank you. I'll check head gasket and for cracked block (hopefully this is not it).
this got me to do some research about using synthetic oil in older diesels and looks like this is bad idea and can lead to problems with gaskets. i was putting expensive synthetic in for the last 3 years and this season kept it till the end of the season with 180 hours on it, thinking it's good oil and I do not need to change it every 100 hours. big mistake.

thanks again for your advise.

Give me a break. There is absolutely no way synthetic oil can contribute to a head gasket failure.

Did this research by any chance involve putting "synthetic oil causes gasket failure" into google?

The gaskets referred to in the regular synthetic oil myth thread are things like crankshaft oil seals, and paper or plastic gaskets for stuff like the valley pan and cam covers. Even if the myth were true, which it is not, the head gasket is a totally different kettle of fish. It's made out of metal.

Back to the real world now. There are some tests you can do to confirm head gasket failure or cracked block. Leakdown test for the cooling system, compression test, & chemical test for combustion gases in the coolant.

The most likely cause in an older engine would be exhaust manifold failure. This is usually jacketed in coolant. When the manifold corrodes, coolant gets into the exhaust manifold and back into the cylinders.

 

[waterant]

If the head gasket was bad, blow by from combustion could back up into the coolant or coolant could leak into the cylinders, causing white smoke at startup.

No white smoke on start up. engine starts like a charm even in cold weather.

The gaskets referred to in the regular synthetic oil myth thread are things like crankshaft oil seals, and paper or plastic gaskets for stuff like the valley pan and cam covers. Even if the myth were true, which it is not, the head gasket is a totally different kettle of fish. It's made out of metal.

Thank you. good to know. I read about paper and plastic. i did not know head gasket is metal. did not have a chance to change that yet.

The most likely cause in an older engine would be exhaust manifold failure. This is usually jacketed in coolant. When the manifold corrodes, coolant gets into the exhaust manifold and back into the cylinders.

I guess crack in block will get much more than 7% of coolant into oil in 180 hours of running this summer. my main suspects are head gasket and exhaust manifold. any test i can do to know which it is or both will result in the same outcome and better replace both?

thank you

 

[MarkSF]

You could try the cooling system leak down test, but I'm not sure it will give a very definitive result, given you have a small leak.

 

[dabnis]

Wondering if you noticed a drop in the coolant level right after you changed the pump? Trying a new pump would be easier than pulling the head? If it starts well & no white smoke at start up & it doesn't heat up, the head gasket may be OK. Maybe try the easy things first? The tests Mark mentioned would also be easier than pulling the head?

Paul T

 

[MarkSF]

Here is what I would do if it were my engine :

Check the coolant for exhaust gas. Examine the coolant for oil.

If negative, change the oil, run it for a while, and take another sample.

Take it from there.

My logic is this : a head gasket separates the combustion chamber from the oil and coolant passageways. The pressures are about 300 PSI, 50, and 15, respectively. That means the most likely result of head gasket failure is combustion gas in the coolant, followed by gas in the oil (probably wouldn't cause any issues), followed by oil in the coolant, and, lowest probability, coolant in the oil. It would be rare (but not impossible) to have coolant in the oil, with a head gasket failure, without the other problems at the same time.

So then let's consider a failed exhaust manifold. If this is the problem, you should be able to see coolant inside the cylinders with the injectors removed. Also inside the exhaust manifold with the exhaust disconnected.

 

[Capt Len]

Is that the engine with the little O rings on the oil line connecting block to head? A head gasket does more than just compression. If manifold cap end gasket is weeping, over time there would be water in the cylinder and then the pan, but starting would likely show some stuttering, knocking, white exhaust or just plain kluncking. Unless this is bad ,more frequent oil and filter change until you get around to pulling the head.Sometimes running without rad cap tight eases the pressure situation Pulling the mixing elbow for a long observation might help.

 

[waterant]

You could try the cooling system leak down test, but I'm not sure it will give a very definitive result, given you have a small leak.

Thank you. Did that last weekend. Should done it long time ago (I was loosing coolant for the last two seasons, not much so i did not bother). Found 3 small leaks due to bad hose clamps. Replaced clamps to high quality marine from defender - on last test cooling system was holding exactly 30psi for over 20 min until I stopped the madness. kind of proud of this achievement
If anybody reading this wants to do the same test (highly effective at finding small leaks which you can see only under higher pressure, I ordered kit from Princess Auto in Canada:
Cooling System Pressure Tester | Princess Auto
also found lots of less expensive kits on Amazon but would cost to much to order to Canada.

Wondering if you noticed a drop in the coolant level right after you changed the pump?

I was loosing coolant for a while but I saw traces of it on drip cloth under the engine so did not think it's going in oil.

Trying a new pump would be easier than pulling the head?

Engine was overheating last season even after I replaced thermostat (tested in hot water - worked fine) and flushed coolant and did everything else I could think off. Replacing the pump resolved the heating problem.

If it starts well & no white smoke at start up & it doesn't heat up, the head gasket may be OK.

Starts right away even cold, no visible smoke at all, just water out, and I resolved overheating by replacing coolant pump (but I changed oil before that was done).

Maybe try the easy things first? The tests Mark mentioned would also be easier than pulling the head?

I did cooling system leak down test and found several leaks because of hose clumps, now system holds exactly 30psi for a very long time. but i'm not sure if it helped with coolant in oil - coolant could not get into oil because of leaking hoses, right?

Here is what I would do if it were my engine : Check the coolant for exhaust gas. Examine the coolant for oil. If negative, change the oil, run it for a while, and take another sample. My logic is this : a head gasket separates the combustion chamber from the oil and coolant passageways. The pressures are about 300 PSI, 50, and 15, respectively. That means the most likely result of head gasket failure is combustion gas in the coolant, followed by gas in the oil (probably wouldn't cause any issues), followed by oil in the coolant, and, lowest probability, coolant in the oil. It would be rare (but not impossible) to have coolant in the oil, with a head gasket failure, without the other problems at the same time.

Sounds like a good plan, thank you

So then let's consider a failed exhaust manifold. If this is the problem, you should be able to see coolant inside the cylinders with the injectors removed.
Also inside the exhaust manifold with the exhaust disconnected. Is that the engine with the little O rings on the oil line connecting block to head? A head gasket does more than just compression. If manifold cap end gasket is weeping, over time there would be water in the cylinder and then the pan, but starting would likely show some stuttering, knocking, white exhaust or just plain kluncking. Unless this is bad ,more frequent oil and filter change until you get around to pulling the head.Sometimes running without rad cap tight eases the pressure situation Pulling the mixing elbow for a long observation might help.

I'll try to disassemble it next weekend to see. I was hopping no leaks in cooling system shows manifold is still holding as any holes due to rust would cause system to loose pressure? Or it's not the case?

And thank you all for your help with this.

 

[engineer_sailor]

I used a combustion leak tester ala:
UView Combustion Leak Tester:Amazon:Everything [email protected]@[email protected]@http://ecx.images-amazon.com/images/I/[email protected]@[email protected]@415T4KN9AQL

to detect combustion gases in the manifold in hopes of ruling out a head gasket issue. Negative readings for me but still worried about false negative due to test fluid not being fresh.

I had a coolant leak at the where the exhaust flange meets with the manifold. There is a path between manifold coolant chamber and combustion chamber at that seal. Maybe unlikely source of contamination but anything is possible on a boat that moves and sloshes around everywhere. Would also resemble a slow leak. Pulling the exhaust is straightforward. Just be careful not to scratch the mating surface and use Permatex on the gasket

Josh

 

[Capt Len]

" Maybe unlikely source of contamination" Not so unlikely, especially with engines wagging a tall header/mixer pipe or a dry exhaust.Good gasket care and torquing will help. Mentioned it to Med in 'hate boats' as a potential source of his water problem and wondered if his manifold was raw cooled.

 

[waterant]

I had a coolant leak at the where the exhaust flange meets with the manifold. There is a path between manifold coolant chamber and combustion chamber at that seal.

" Maybe unlikely source of contamination" Not so unlikely, especially with engines wagging a tall header/mixer pipe or a dry exhaust.Good gasket care and torquing will help.

Is this gasket on the side shown by the red arrow here Westerbeke W21 Cooling System ?

I also disassembled the section inside red box Westerbeke W21 Cooling System when i replaced coolant pump and thermostat. coolant was running everywhere when i did that. is there a way coolant could get into oil when i did this?

I guess changing oil and running engine for 50 hours and testing oil again will show if it was one time thing or it's a constant leak but i'm in good cold canada and boat will be a bear cave under the snow for the next 6 months. I'd better make sure everything possible is fixed before the next short boating season here.

Thank you

Ant

 

[engineer_sailor]

No, it's item 12

 

[waterant]

got it. Thank you.