fresh water in oil

[joesig]

Last week I went to the boat to run the engines in my slip. It is in fresh water river a little north of lake Pontchartrain outside of New Orleans, LA. I checked the engine oil and coolant level in both DD 6V92TA engines before starting them. The levels were normal full, about 2" below the cap on the heat exchanger and at the F mark on the dipstick. After running in the slip for about 40 Minutes at 600 to 1100 Rpms the engine temperature on my Digital gauge on the bridge indicated 125F which is normal in the slip. I went down in the engine room while they were running at ~ 750RPMs and both engines sounded great, I felt the water cooled manifolds and risers going to the single water cooled turbo all seemed good. I climbed out of the engine room, closed the hatch and went to the bridge to shut down the engines. I shut the stbd engine first then the port. After shut down I went in the cabin to find signs of smoke. I opened the hatch and there was a light smoke atmosphere in the engine room, no signs of fire. After blowing out the smoke of the saloon and engine room and allowing the engines to cool down a little I checked the engine oil on the stbd engine, it was about 3/4" high on the dipstick. Port was normal. I opened the cap on the heat exchanger and the coolant level was normal. The airsep filter on the stbd engine smelled a little smokey, if that makes sense. The engine have not been run hot since the rebuilds about 250 hrs ago. I decided to drain some of the oil out in the stbd engine to get the level back to the F mark on the dipstick. I removed about 2 quarts of oil to get the level back to where it was before starting it. It did not look milky at that time. I decided to call my mechanic and ask what good have happened. He recommended that I bring him the oil I removed and would send out to lab for analysis before doing anything. The oil analysis came back indicating that there was fresh water in the engine oil. I use Detroit Diesel Power Cool Plus 600 with distilled water at a 7% ratio. Since it doesn't freeze that often in my area I don't need the antifreeze protection. I called the lab and spoke to the owner and explained the circumstances and informed him on the type of coolant I use and that it contains ethylene glycol. He said there was no trace of the coolant in the oil sample and the water was fresh. The boat is in fresh water at the slip and no rain water could have entered the system. My mechanic is scheduled to be at the boat this coming week to start to figure out what happened. In the mean time I changed the oil and filter and removed the starter so he could remove the air box covers and look in the engine. The engine has not been started since shutting down last week. The fresh water has me baffled, where could it come from also, what about the smokey conditions. Both engines were running great. Any thoughts would be appreciated.
Joe Signorelli
1985 Chriscraft 422 Commander
Barbara Ann

[Scarlett]

Just did a survey on a Hatt 70 with 12-92’s same problem. It turned out to be the raw water pump seal allowing water to work its way down the shaft and into the engine. On this boat the raw water pump was mounted with the weep hole up, not down so the water did not drain out the weep hole as it should have and instead was able to get down the shaft and into the engine. This discovery came after taking pictures of all the cylinders looking for leaking liners, luckily the real problem was discovered befor the heads were removed. John

[racclarkson@gmail.com]

Busted after cooler I’m thinking. Would wet turbos also be in the running? Great you’re in fresh water.

[Briankinley2004]

Are you in the Tchefuncta River?

[joesig]

Just did a survey on a Hatt 70 with 12-92’s same problem. It turned out to be the raw water pump seal allowing water to work its way down the shaft and into the engine. On this boat the raw water pump was mounted with the weep hole up, not down so the water did not drain out the weep hole as it should have and instead was able to get down the shaft and into the engine. This discovery came after taking pictures of all the cylinders looking for leaking liners, luckily the real problem was discovered befor the heads were removed. John

I will inspect raw water pump and look for signs of seal leakage , Thanks, Joe

[joesig]

Are you in the Tchefuncta River?

Yes, Marina Del Ray, Joe

[joesig]

Busted after cooler I’m thinking. Would wet turbos also be in the running? Great you’re in fresh water.

After cooler and turbo have coolant, no coolant found in oil analysis, Thanks, Joe

[rustybucket]

When was the last time you ran her up? The water in oil could just be condensation, but that doesn't explain the high oil level.

If the oil wasn't milky I doubt the water in the oil contributed to the smoke. I think you need to find the source of the smoke first. I would have guessed diesel in the oil, but if the test came back negative for that.....

When you pulled the oil out, was it pulled from the bottom of the oilpan? The water should have been on the bottom, so when you sucked some out you should have gotten straight water almost.

Idling for 40mins in the slip isn't really good for these engines although, other than some slobber and potential carbon buildup, I don't think it would hurt them. They really need to be loaded to test/check much of anything.

I guess I'd crank her again in the slip and look for signs of smoke. Sometimes it helps to turn the engine room lights off and use a flashlight or headlamp to inspect everything. You'd be surprised what you can see with all the lights off and a concentrated beam, really highlights stuff like smoke and assists in finding the source.

[davidwigler]

When was the last time you ran her up? The water in oil could just be condensation, but that doesn't explain the high oil level.

If the oil wasn't milky I doubt the water in the oil contributed to the smoke. I think you need to find the source of the smoke first. I would have guessed diesel in the oil, but if the test came back negative for that....

I was thinking condensation too unless the oil was milky in color.

[madhatter1]

Just did a survey on a Hatt 70 with 12-92’s same problem. It turned out to be the raw water pump seal allowing water to work its way down the shaft and into the engine. On this boat the raw water pump was mounted with the weep hole up, not down so the water did not drain out the weep hole as it should have and instead was able to get down the shaft and into the engine. This discovery came after taking pictures of all the cylinders looking for leaking liners, luckily the real problem was discovered befor the heads were removed. John

it sure sounds like this is the most likely cause. Boats like to be run a lot to stay operational. Keeps everything lubricated, heated, and corrosion (rust) free. Things like seals will dry rot and harden over time.

So What Scarlett says actually makes sense. After some run time it seems the seal let go just before shutdown. You get fresh water in but didn't stay running long enough to mix up and get milky. Hopefully this is the case and you dodge a bullet. Good luck.