How to get water out of an engine

Background: We have a sailboat with a diesel engine. On this engine is a heat exchanger where raw water goes thru some tubes and hot oil goes over the tubes in order to be cooled. We had a failure, and raw water mixed into the oil and got into the engine block. Not good.

The heat exchanger is now repaired, and my husband has done 3 consecutive oil and filter changes, running the engine between changes. He was able to suck out a lot of water the first time, and now he’s left with slightly milky oil - so there’s still some water remaining.

Any suggestions on getting the rest of the water out? Is there something we can add to the oil to break the emulsion? Or do we just keep changing oil till it’s clear?

It runs ok (i.e., the water didn’t lock the cylinders when it flooded?) I’d say that you and your husband are on the right track. You might do another oil change, but after that I’d just run it for a while and let the water evaporate.

I’m pretty sure there’s a product in a little bottle you can buy and pour into your tank that removes water.

Wish I could remember what it’s called. I think I got it at Auto Zone.

The engine seems to be running fine - he had it on and off several times as he changed the oil, and the last time, he just let it run. It’s something like 30 years old, so I expect it was pretty well lubricated before the water incursion.

Large Marge, I think what you’re referring to is for the fuel tank - I’ve never seen one for oil, but it won’t hurt to check. It’s not like this is a typical problem in cars, as far as I know.

We’ll be heading back over to the marina later today - we shall see what awaits. Meanwhile, any more suggestions of ideas are most welcome!

You live in Mechanicsville and you’re asking us?


With a straw, of course!

If the oil is just slightly milky, there is not much water, and it may evaporate with just running the engine. ARe we talking fresh water or salt water? I would not be so worried about fresh, but salt would concern me.
He is changing the filter when he changes the oil right?

Funny thing about Mechanicsville - I see Amish farmers all over the place, but not so many mechanics… :stuck_out_tongue:

The water is pretty fresh - we’re in a creek off the middle of the Chesapeake Bay - about 90 miles or so from the ocean, so it’s not really salty at all. Plus we’ve had a lot of rain this spring. And yes, he changes the filter every time. After the 3rd change and after running the engine a bit, the oil was ever so slightly milky looking. I did a touch test, and it was most definitely slick.

We ran the engine about 30-40 minutes today, under load (in gear but still tied to the dock) and we’re thinking next week we’ll do one more oil and filter change, then venture forth. What the heck, we have BoatUS with the unlimited towing option, so if the worst happens, we’ll be taken back to our slip. Keep a happy thought!

Thanks for the input!

The only thing I ever did when a head gasket had allowed coolant to gank up the oil is the change which you’ve done, but I added a quart of Rislone in place of one quart of oil, just to chase out any lurking schmutz in the hydraulic lifters. Ran it for a week, making sure it had plenty of time at operating temperature, and then did a regular oil change.

Thank for the info on Rislone, dances - I went to their website and it sounds like a good idea. Even my sweetie thinks so! We’ll give this a try next weekend!

Keep us posted because if you don’t have it clean in 2 more changes, something is still, wrong or you are not getting a good change.

Are you using one of those little pump out tubes or can he get to the bottom of the engine to the regular drain plug?

What I do on my bikes to make sure I get all the old oil out and what might work in this instance is if there is an oil return line, leave it off and collect the oil as it comes out. Then just keep adding oil as you run the engine until there is new and clean oil coming out. Usually takes about 2 quarts to flush all the coolers and lines.

NOTE, do not do this if you are unsure of the oiling system because if you do it in the wrong place, you can deprive the engine of oil at some needed place and ruin it.

Call the engine manufacture and ask them what they recommend.

GusNSpot, this engine is a 1975-ish 80-HP Sabre diesel. Sabre is part of Perkins-Sabre now and I know my husband had been talking to their reps. I’ll tell he what you suggested about flushing it out.

He’s been using a pump to remove the oil since the drain plug is very hard to reach - our engine room is small and my husband is a big guy. We need to find a 5’ tall, 80# grease monkey, I think. Although the next time we change the oil (probably this weekend) he’s going to try to remove the plug and get the last drops out.

Thank goodness the convenience center near us has a tank for recycling oil - we dumped about 10 gallons off yesterday!

That was the only other thing I could think of-putting down some absorbent pads beneath the oil pan and letting the stuff that can’t be suctioned out do a drizzle. Then you can throw away the pads and not worry about fouling the bilge.

Oh … good plan … save a lot of messto pump then drain… Yeah, need to go by the middle school and kindnap … er is there not a good kid in the marinia?

The area under the engine is carpeted with the absorbent pads - they’re a life saver! Especially the time the oil filter wasn’t seated properly and it sorta leaked… ick. And he was thinking about sucking out as much oil as he could, then draining the rest from the bottom. We’ll see this weekend.