still unidentified fluid in water

[Andy]

This is the second chapter in the ' water in oil' problem. BMC 1.5 inbd diesel, all problems started arond the time after the cylinder head was removed, since then it has been removed again , had pfd crack test carried out and checked for warp. The sump has now got about 1 1/2 pint of extra fluid in it but the fresh water in the heatexchanger tank is the same level.The seawater pump is remote from the engine (belt driven). The exhaust does not seem to be running back . The fueltank is slightly higher than te engine and has been nearly empty all winter.
The sludge in the sump has the same appearance as Baileys (drink)
Any more good ideas???

 

[gunnarsilins]

Can it be....

...transmission oil?

 

[brianhumber]

Your first lot of replies covered most of the usual causes. I have not seen the following on yachts before but have exprienced it on 'proper' ships engines.
You mention a brown 'baileys' sludge in the sump. I wonder if the jolly old microbes have made a home in your sump. They could be breaking down the oil into a sludge and oily water type fluid (much as the sea does to natural oil seeps on the sea bed) You mention a lot of water for this theory, I wonder how long it has been before you lasted drained the water off. If this is is a possibilty I am afraid it means you must ensure all sludge is removed from all the engine/ sump by flushing oils etc . Console yourself that your sump does not have 5,000 galls in it but you could issue yourself with a couple of bottles of port as 'crankcase sump bonus'

 

[brianhumber]

Re: Can it be....

As good a suggestion as my idea. I once had an '76 1.5 and seem to remember there was a felt seal between the engine and flywheel which would have let any gearbox oil out before entering the sump. Maybe the design changed in later models.

 

[mtb]

Re: has the engine been sitting in water

after checking the compression figures ,( you did do this Right ) there are not many options left had it been a liner surely the piston would have gone through .
If the engine has been in water it may have condensated or the water seeped in through the crankshaft seals. Have you drained the engine then flushed out before refilling with new oil to see how long it takes to build up .
What some one else said about the water being drawn back into the manifold is actual a possibility ,if your water is injected into the exhaust then is it after and below the last downward bend of the exhaust pipe.
Did you run the engine during frozen conditions ,because if the outlet was frozen the water would not escape cause back pressure / hard starting, water in engine !!
You must start right from the beginning and do the basic tests on the engine and work through all possible causes .
Why was the head taken off in the first place !! you see you did not tell us that to begin with ,how can you expect people to give their opinions if you don't tell the whole story .
Sorry a bit of a whinge I know but you see along with many others I actually work in the trade and so the opinion you get from people like my self costs by that I mean years of training and experience . The point being you need to play the game re if asking for advice by giving all the information relevant .
I had this a while ago some one took the piss re advice I gave ,but in the trade what I said is exactly how it would be done through his arrogance I very nearly said bollocks to it why try to help !!!.
Now that said
good luck
Mick

http://homepage.ntlworld.com/boats
I want a big steel ex trawler / tug v/cheep or swap for tug

 

[Guest]

What you describe as "Baileys" is undoubtedly an emulsion of water in the oil. There really isnt anything else it can be.

If your fesh water circuit is still full and not salty (try a small drop on the tongue - dont swallow) then water must be getting in via the raw water system. Obvious place to look is the exhaust manifold, where corrosion at the injection point can cause water to flow back into the cyliders and then the sump when the engine stops.

 

[Trevor_swfyc]

Seriously,
You should not leave the tank empty due to the very high humidity and cool nights you could get a considerable amount of condensation in the tank.

Not so serious,
With the amount of water you are getting pehaps you had better drain the oil before the sump overflows.

Very silly!
Take out the engine and export it to the desert could be a good earner!!

Beats me.
Trevor.

 

[burgundyben]

Diesel

Just had a look thru previous posts, I agree with Boomer, are you sure its not diesel from the lift pump?

Have you taken a sample of this fluid for analysis?

Other than that MTB seemed to have it well covered.

Last ditch answer from me, I once had a car I could not fix, so I sold it!

 

[burgundyben]

Diesel

Just had a look thru previous posts, I agree with Boomer, are you sure its not diesel from the lift pump?

Have you taken a sample of this fluid for analysis?

Other than that MTB seemed to have it well covered.

Last ditch answer from me, I once had a car I could not fix, so I sold it!

Doubtless BarryD will call me dull again now for having attempted to say something useful.

 

[Col]

Your exhaust manifold isn't corroded through between the water jacket and exhaust passage is it? When engine switched off, this would allow water to drain into cylinder via open exhaust valve, if your piston ring and bores are worn, water Would leech into sump past pistons.

<P ID="edit"><FONT SIZE=-1>Edited by Col on Wed Feb 13 22:49:48 2002 (server time).</FONT></P>

 

[Andy]

Thanks for all replys...i have printed them all off (i'll read them in bed). Only just got back from yacht club but i have given a sample of oil to a scientist tonight to establish what exactly is in the sump....you can find out tomorrow night or friday!!!

 

[Trevor_swfyc]

For a while I was quite taken with the bug theory, but the engine oil gets hot and this kills off the bugs and the bug theory.
So I looked back at your original posting in particular "IT TAKES TIME TO START"
is this a clue, it is well documented that if an engine does not start easily continual cranking could cause water to back up into the engine as the highest point in the exhaust is higher than the engine exhaust outlet. The answer is to leave the salt water pump inlet valve shut until the engine fires up, then immediatly open the valve.
If you were only running your engine for say 10 min a day, which would result in damp/ wet oil that is being warmed daily, especially if you were using a vegatable based oil. Then I could be converted back to the bug theory.
No doubt we are all looking forward to hearing your lab results lets hope its not bad news / expensive.
All the best
Trevor

 

[Juggler7823]

This is a curious problem but I do not thiink you have the answer. Water can geet into the engine by continuous cranking with the water on but it gets into the cylinders via the exhaust valves and quickly stops the engine.

Roy

 

[vyv_cox]

No need for a lab test - do your own "crackle test". still used in refineries. Heat a steel plate (old frying pan) on your stove for a few minutes until it is good and hot. Drip some drops of your emulsion onto it. If there is more than 0.2% water in it it will crackle.

 

[Trevor_swfyc]

Re:Crackle Test

Yes we used this test for trace quantities of water in base oils, actually it would detect water down to 0.01% w/w water. As your oil contains zinc thiophosphates (anti wear additive) it will give off some nasty fumes so I would recommend you carry out this test outside and as said only drip on a very small quantity.
Oh and eye protection is now mandatory if you want to start doing your own testing.
This is a positive or negative test but degree of crackle/spitting gives some indication of amount. For actual water content you would have to carry out a dean stark.
Happy Testing
Trevor.

 

[oldharry]

Re:Crackle Test

If you are not losing secondary coolant, the contaminant must be raw seawater. Do you have a manifold mounted heat exchanger? If so the seawater could be leaking into the manifold and entering the engine that way. It would also account for the poor starting.

It should not be difficult to seal up the outlet, and pressurise the water jacket (a hosepipe from the water main should be sufficient) to show up any leaks.