Water in Oil, Merc 260

Hey guys!

Okay, so there are plenty of post regarding water in the oil in this forum. I downloaded (and printed out!) the Mercury Service Bulletin 2001-13 regarding water intrusion. But I figured I'd share my situation anyway . . .

I bought an old boat. 1988 Sea Ray 230 Cuddy Cabin. It's in good shape. Has Mercruiser 260 in it, a rebuild. Original block apparently, with all other parts 1 - 3 years old. Had the marina mechanics (yes it was $$$) do an outdrive repair & engine tune up. Everything was working fine. [Note: I assumed an engine tune up included oil & oil filter change, but invoice indicates this was not done].

I've checked the oil once or twice and it was fine. Checked on cold engine though. Today I had to replace altenator belt. Let engine idle for about 15 mins. Checked oil. Dipstick was covered in oil top to bottom. The bottom part of dipstick showed mayonaisse-ing, the top part showed normal oil. Except top of dipstick, where it's bent like an "s" had some mayo on it. Pulled oil fill cap, mayo on underside of cap, but also normal oil there as well. So far, no real chocolate milk, that is to say, it does not appear that oil and water have thoroughly mixed yet. (Am I saying this right?)

The boat shows evidence that water rose very high in the bilge, or the boat partially sunk. Water line is above oil pan, half way up batteries. Marina mechanics pointed this out, but made no big deal about it, especially as pertains to oil/water mix. They were more concerned about engine rust and electrical cables (cables were replaced). Mechanics did change the plugs, and did not mention any signs of oil/water mix or of water in cylinders, or of messed up old plugs. They also did a sea check and ran boat at about 4500 rpm for 20 mins and gave me the thumbs up.

Am I screwed? Engine runs great other wise, sounds very good. Mechanics would have spotted a cracked block/manifold you'd think, right? I plan to change oil, oil filter, inspect plugs and cylinders in the morning.

I guess my real question is: has anyone ever seen mayo at bottom of dipstick, good oil at top of dipstick? And what might this indicate? Is mayo better than chocolate milk? [Not a food preference question.]

I know it is possible that water from flooding of bilge may have entered engine and wound up in oil pan. How likely is it that this is causing mayo situation? Or is mayo nearly always the result of blown head or riser gasket, bad manifolds or risers, or crack somewhere? What percent of water in oil problems do not result in the need for new engine or rebuild?

I was also in very rough seas last time I was out. Plus, the reason I had to replace alt. belt is that is broke off while at sea. (I managed to power home anyway.) Could either of these things possibly added the water into oil?

Any advice regarding next-steps, other than what I set out to do with complete oil change and spark plug and cylinder inspection?

ANY info or advice will be GREATLY appreciated. Thanks in advance.

Cheers,
Lou

Re: Water in Oil, Merc 260

Emulsified oil on the bottom part of the dipstick with clear oil on top will occur if the engine has sat for a while, if not alot of oil was ingested, and the engine was run for a very short time with water in it. (It's starting to seperate)
It will also occur if fresh oil is added, and oil is checked before running engine, to an engine with emulsified oil in it.
To clear the engine, first drain the oil and replace the filter. then refill the engine with clean oil, run it until the engine gets to operating temp and drain oil/replace filter.
Repeat until oil looks normal.

And never assume anything when taking a boat in for work. Be it a tune up, service, or anything else. Ask them what their tune up entails. At my shop, a "tune up" doesn't include oil and filter. But we'd have explained that a service was probably needed, and no boat leaves my shop without every fluid level checked and noted on the work order.
Your boat leaving that shop with water in the oil, and no notification to you is inexcusable.

Re: Water in Oil, Merc 260

Hava . . .

Thanks for the reply. I'm off to check things out. Thanks for the advice. It could be old oil, never thought of that. Hopefully it is, with maybe a touch of water in it, from condensation or else from entering through exhaust. Thanks again, let you know how things turn out.

Re: Water in Oil, Merc 260

No luck. Ran 5.5 quarts of new oil through, made YooHoo. Did this in slip at idle. Actually looks worse than before. Chocolate milky oil seen under valve covers. Oddly when I went to drain old oil, very little came out, even though it was reading high on dipstick. No oil in bilge though, no sheen on water. The 5.5 qts. passed through fine, but perhaps a bit slow.

In my haste, I never changed oil filter, does anyone think that this would of choco-fied the new oil? Maybe some water was still in filter? But I figure some of the oil would have come through clean, or cleaner. Just how much water does it take to turn 5.5 qts. of oil into rich chocolate milk?

Anyone think I should pass another 5.5 qts. through again with a new oil filter to see if things improve, or have I passed that point?

More background info: when I mentioned I had to change alternator belt, it was because it shredded at sea. It became loose and self destructed. On way back to marina (maybe a 4 mile cruise), I hit a small, muddy sand bar. Just barely hit the drive and prop, was never beached. Did not overheat, but did warm up a little, maybe 10 degrees. The boat runs a bit cold at about 125 degrees at 30 mph. I've either got a bad t-stat, the wrong t-stat, or a clogged t-stat. Or maybe even no t-stat. Dumb question: any way any of this may have contributed to oil in water? Everything was fine before this ill-fated trip. Coincidence or something more?

Any next step suggestions other than tear down the engine and look for blown gaskets or cracks in block or manifolds? (For what it's worth, the engine does not make any noise that would indicate blown gasket).

Thanks in advance!

Lou

Re: Water in Oil, Merc 260

Have to change oil more than once to get water out. Yes you need to change the filter everytime. Maybe 4 times maybe 6 but if it looks the same everytime then its time to check ehaust manifolds and block for freeze damage. Are you getting any water in the bilge area while running.

Re: Water in Oil, Merc 260

cooter2506 said:

Are you getting any water in the bilge area while running.

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Yeah, getting water in bilge while running, but no more than when not running. Why did you ask, what might this indicate, or not indicate?

Thanks for your reply & input.

Re: Water in Oil, Merc 260

havasuboatman said:

E
Your boat leaving that shop with water in the oil, and no notification to you is inexcusable.

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There was no water in the oil at this time. I had checked the oil condition before and after boat was at shop and all was well. I try to check oil every time before I go out, and again when I get back. But I do forget often. Especially if we caught a lot of fish.

Re: Water in Oil, Merc 260

More BAD news . . .

Did two more oil and oil filter changes, making three total. Problem persists. May be getting worse actually. I put in 5.5 qts. oil, and suck out nearly 8 or 9 qts. of emulsified oil. And the shade of chocolate milk appears to be getting lighter, or at least staying the same. There's no indication the new oil going in is purging out water. It seems I have a milkshake factory on my hands.

Probably going to call in the pros. I am pretty handy and have decent mechanical skills, but I am not exactly sure what to look for in a strip down on this engine. If this were a 3.0L, yeah, I'd pull it apart, as I've done so on that engine twice before. But this 260, it's unfamiliar territory to me. MAYBE I will tear it down and let pros examine the parts, determine failure point, and reassemble. The might save me some money. But it will take time, which I do not have a lot of. Plus, I think a pro mechanic will be able to find failure point as he strips down, maybe saving some unnecessary work.

Question now is: rebuild existing engine, or buy reman and drop in? As I mentioned before, this engine has relatively new manifolds & risers (2 - 3 years), but block seems to be original. Any advice, opinions, suggestions? Sympathy???

Re: Water in Oil, Merc 260

Question now is: rebuild existing engine

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An engine that fills up that quickly with water sure sounds like a cracked block.

Re: Water in Oil, Merc 260

Why not pressure test the engine's cooling system first? That will tell you if the block is sound internally or not. Even the best mechanic cannot "spot" an internally cracked block from the outside, if they question the soundness of a block they do a pressure test.

Regarding changing oil to flush out all the water, water is not just hiding in the block waiting for the new oil to purge it. The water is coming into the block and leaking internally into the crankcase via cracked or otherwise compromised coolant water passages as it is being run with the new oil in and raw water supply on.

The intake manifold does have coolant running thru it, it is not unheard of that they have rusted thru and allow water to go right into the crankcase. Pressure testing will catch this.

Re: Water in Oil, Merc 260

Good news!!!

Turns out the electric oil extractor pump out kit I bought was defective and did not manage to pump out all the oil. (Yeah, I should of caught it earlier.) So I was pouring good oil into bad. Went back to the old Moeller hand pump oil extractor and managed to suck (nearly) everything out of the pan. Two oil changes later and the oil looks fine. Only ran the engine at idle though for about 10 mins, and at about 2000 rpm out of gear for 2 mins. Plan to do a couple of more oil changes then a sea trial.

Assuming there is no crack or gasket failure, and the sea trial goes okay (yeah HUGE assumption), here are my guesses as to how water got in oil . . .

1. I hit a muddy sand bar, maybe the exhaust holes got plug up enough so exhaust water ran back into engine.

3. After hitting this sand bar, I moved the out drive to full trailer up position and allowed tide/current to dislodge us. The seas were very rough, about 3 foot waves. Maybe the drive being up and the waves allowed sea water to push up through the exhaust.

4. I continued to fish in these seas, and at certain times the boat was pitching nearly 30 - 35 degrees. Maybe waves pushed up through exhaust and risers? There are flappers in those risers to prevent this, right? Perhaps one or both are shot?

5. My t-stat is shot. Opened the housing, and the t-stat is not functioning and has not been since I took ownership of the boat. She's been running wide open. Read in the Seloc book that this can cause water in oil due to condensation forming internally in the engine since it is running too cold. Temp gauge had been indicating only 120 - 125 degrees while cruising. This seems like a long shot to me. I mean, just how much condensation can actually form this way? Enough to spoil oil? Also those Seloc books, you never know with them.

6. All of the above.

Wish me luck in my next steps.

Re: Water in Oil, Merc 260

Update:

T-stat is shot, replacing. In process, determined intake manifold is shot. Screwdriver went straight through. Replacing intake manifold. Most likely source of water getting in oil at this point. Give me a week or so to post how things turn out.

Re: Water in Oil, Merc 260

all I can say is WOW.........was that salt water? If so, it might pay to change the oil again and run it without any cooling for a few seconds to get fresh oil all around............just my opinion.

Re: Water in Oil, Merc 260

FreeBeeTony said:

all I can say is WOW.........was that salt water? If so, it might pay to change the oil again and run it without any cooling for a few seconds to get fresh oil all around............just my opinion.

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Can't run a merc. for a few seconds without smoking the impeller.

Re: Water in Oil, Merc 260

Assumed outdrive would be removed............purpose was to get fresh oil on the bearings............while waiting to replace intake mani