Raw water in Oil

[bobofthenorth]

A small amount of raw water will boil off when the engine gets warm - that's a normal event for condensation in cold climates. OTOH, if the water is actually engine coolant that's a matter for serious concern because glycol in the oil will take out bearings.

[delmarrey]

Originally Posted by gjordan

Good luck getting the grey goop out of your engine. I rebuilt a diesel that had been run for a while with water in the oil, and that grey goop was almost like an uncured epoxy. Getting it out of all of the small oil passages was the really hard part. _____Grant.

Here's an old wrecking yard trick.
Before the next oil change drain half of it and dilute what's in the crank case so it's 50/50% oil/diesel and run the motor until warm and shut it down. Let it settle for about 15 minutes and drain it. Then take the other half of the oil and put it back in with diesel and run it again like the last time. Then drain.

Add a quart of cheap oil and let it settle for 15 minutes and drain. This will get out the left over 50/50 mix. Then put in you regular oil.

If that don't do it, start over on the next oil change. But once the engine has been run for a while, what's left may just evaporate out.

[MarkSF]

The 5424 raw water pump has two slots in the casing, the idea being that if the shaft seal fails, the raw water will drip out of these slots and not into the engine. The trouble is that long term leakage will corrode the slots closed, and then the leaked water has to pour into the engine instead via the drive - it has nowhere else to go.

This is why any leak from the raw water pump is unacceptable, and must be fixed.

[gjordan]

I have some very old diesel tractor manuals that say after a certain amount of hours (cant recall the number) to fill the crankcase to its normal level with kerosene and run engine for 15 minutes or so, and then drain and put regular oil in. That was considered a normal cleaning method before motor oils were greatly improved. Detergent, ashless dispersent ,etc made things much better. As far as the grey goop, I used diesel to clean the whole insides , and diesel barely cut that goop. Maybe running your engine up to a good operating temp will make it wash out ok. After having had a couple of diesels run away on me, I would never try that crankcase full of kerosene trick. I hope the OP keeps us up to date on what works for him or what doesnt.____Grant.

[shamrock]

Originally Posted by Sheepshank

I just installed a new to me yanmar 3gm30f .Runs great but water pump was leaking a bit.Should i be worried about water intrusion into the oil also,oil looks good now.Plan on rebuilding water pump next time I am at the boat,but would like to move the boat a couple miles to another location first.Would this be advised against?

Hi,

It looks like the posts are still addressing the problem I had as opposed to your current concern.

I would not worry about running the engine for now. My big lesson here was to check the oil before every start. If I had done that, I would have noticed grey oil earlier on and avoided other poblems.

If you can see the water dripping out of the water pump housing, that does not mean necesarily it is leaking into the engine. That means the forward seal needs to be replaced and I would not just assume the rear seals are shot and water is going into the crankcase.

I think I have a happy ending after changing the oil 4 or 5 times to be safe, it seems to be running fine. All was well until Sandy!!!

Good luck and rebuilding that pump is probably a good idea when you have time.

[bobconnie]

Old timers trick, use 50% kerosene 50% good diesel engine oil, if ya have a non spin on filter(canister type) leave it empty, run engine at a fast Idle for 15 20 minutes or until ya get some heat in it ! drain this mixture, and do it again, drain install filter and replace with a good diesel engine oil and run it ! it's always worked for me to clean out a engine after a water to oil leak!! just my 2 cents This of course is after repairs are made !!

[shamrock]

Originally Posted by gjordan

I have some very old diesel tractor manuals that say after a certain amount of hours (cant recall the number) to fill the crankcase to its normal level with kerosene and run engine for 15 minutes or so, and then drain and put regular oil in. That was considered a normal cleaning method before motor oils were greatly improved. Detergent, ashless dispersent ,etc made things much better. As far as the grey goop, I used diesel to clean the whole insides , and diesel barely cut that goop. Maybe running your engine up to a good operating temp will make it wash out ok. After having had a couple of diesels run away on me, I would never try that crankcase full of kerosene trick. I hope the OP keeps us up to date on what works for him or what doesnt.____Grant.

After flushing the oil a few times, and running the motor at full temp, I think I was able to flush the bad oil out. The governor was definitely fouled from the grey oil and I was having a serious hunting problem (rpms going up and down). I was trying to fugure out how to get access to the governor to clean it and that seemed like a real chore, I would have had to removethe timing cover and everything.

Finally, after putting some hours on her and running hot oil through, the hunting stopped.

I did some cruising in October and the engine ran fine. The ony thing that I am noticing is that the RPMs might not be reaching the max 2700?? I can get her to run at around 2400-2500. I'm not sure if this is still governor related or even a problem at all as I don't run the motor that high anyway. But, if anyone has thoughts I'd love to hear...

[Sheepshank]

I dont have water in the oil yet, but do have a leaky waterpump ..My question is ,how long is to long after you notice a leaky waterpump before water intrusion is a concern.we did run it for thirty minutes at dock and started and shut it down a number of times . I will get it fixed before running too much more.Thanks guys for the tips.

[roverhi]

We had a problem with the antisyphon valve not working on the Engine in our Westsail 32. It would allow water to syphon into the exhaust and into the engine through an open exhaust valve. Water would bypass the rings and get into the oil. If there was enough water in the cylinder, it would hydrolock. Happened twice before I got rid of the valve and just vented the water overboard through a small diameter tube. Anyway, changed the oil and ran the engine till it was thoroughly warm to boil away any moisture in the engine. Went through three warm-up/change the oil iterations each time. Didn't seem to hurt the engine as long as it didn't start on the dry cylinder before it hydrolocked. The engine ran for at least 15 more years before the subsequent owner replaced it.

[shamrock]

Originally Posted by Sheepshank

I dont have water in the oil yet, but do have a leaky waterpump ..My question is ,how long is to long after you notice a leaky waterpump before water intrusion is a concern.we did run it for thirty minutes at dock and started and shut it down a number of times . I will get it fixed before running too much more.Thanks guys for the tips.

Noticing a drip from your water pump does not mean water will ever get in your engine. There should be two different seals, when one goes, your pump will visibly leak, when the other goes, your pump will not visibly leak, but water will run out the back of the pump and into the crankcase. If Your water pump is anything like mine, the seal that you get with your impeller should be replaced, and/or the housing bolts need to be tightened and the leak would stop. for water to get into the engine an entirely different seal would need to leak. My water pump was not visibly leaking, yet water made it's way into the engine.

There is no reason to suspect you are getting or will get water in your oil.

[gjordan]

Shamrock, having less RPM at this point might have nothing to do with the oil problem. Might be that you collected a load of growth on your prop.___Just a thought.____Grant.

[shamrock]

Originally Posted by gjordan

Shamrock, having less RPM at this point might have nothing to do with the oil problem. Might be that you collected a load of growth on your prop.___Just a thought.____Grant.

Thanks Grant, That's what I was thinking too, but am experiencing the same thing in neutral.

[noelex 77]

Originally Posted by shamrock

Noticing a drip from your water pump does not mean water will ever get in your engine. There should be two different seals, when one goes, your pump will visibly leak, when the other goes, your pump will not visibly leak, but water will run out the back of the pump and into the crankcase. If Your water pump is anything like mine, the seal that you get with your impeller should be replaced, and/or the housing bolts need to be tightened and the leak would stop. for water to get into the engine an entirely different seal would need to leak. My water pump was not visibly leaking, yet water made it's way into the engine.

There is no reason to suspect you are getting or will get water in your oil.

Many / most raw water pumps have a a weep hole, or slot behind the rear seal. if the real seal fails water will drip out of the back of the raw water pump allerting the owner to the problem.
There is another, usually identical seal on the engine side of the pump. if this fails you usually get oil out of the weep hole as the weep hole is between the two seals.

With a failure of the rear seal its unlikely for water to get into the engine, but it can occur, particuarly if the weep hole is blocked allowing some pressure build up, but its also requires failure of the second seal on the engine side.

The seal should be fixed, but operating the engine with a defective rear seal to the water pump is unlikely to get water into the engine and is reasonably safe.