mercruiser 898 oil in water

[ojohn]

I have mercruiser with "898" stickers on valve covers and outdrive. It is two barrel with log style manifolds. Engine was installed several years ago by home based "marine mechanic" who said he had the engine built by local marine builder. Rest of the drive setup was transferred from wrecked boat. Remanufactured block has about 175 hours on it, including tune up and fooling around time on the trailer. Engine over-heated on trailer when thermostat stuck and I didn't pay close enough attention. I changed thermostat, ran engine on trailer for about an hour. There was no immediately apparent damage. Boat was stored, as it has been since new engine installation, in unheated but covered building in rainy Oregon. Drained as usual: two plugs on block (each side); one plug on each manifold; and one plug on each elbow. Power steering cooler hose disconnected from pump housing and filled with antifreeze until outdrive drips green. All this one year ago. I go sick and I did not run boat at all until June. My daughter and her friends took it out and came back after three days of playing on the water with engine noise and the oil very milky with water. Local marine mechanic (different guy) said lifter noise and water was from condensation. I thought probably head gasket. He flushed with transmission fluid/oil and changed oil, and gave it back to me. I found oil still milky after a few minutes running on trailer. I have changed oil three times, with new filter last time. I still see a little cloud in the oil, and now I am finding particles of something on the dipstick, and still have some kind of valve train noise. Question; How do I start to decide for sure where the water is coming from? Do I have great risk of further damage by letting it sit longer? Can I, as novice, tell what the problem is if I remove manifolds and heads? Sorry this is so long, but I just want to ask clear questions for your consideration. Thanks for any help figuring this out. John

 

[loadnet]

Re: mercruiser 898 oil in water

You may just have plain ole condensation build up - however!<br /><br />- Are you gaining oil volume in the pan?<br />Pull the dip stick and make sure the oil is right on the money or does it seem to be getting higher and higher reading on the stick?<br /><br />If you are gaining oil on the stick you are for sure, getting water in the oil.<br /><br />Water in the oil can cause <br />- your oil pressure to drop.<br />- noisy lifters<br />- milky condensation build up under the oil filler cap.<br /><br />If that's the case you may have a blown head gasket or cracked manifold/s.<br /><br />Get her to a Marine Doctor and have em do a compression test for you.

 

[ojohn]

Re: mercruiser 898 oil in water

Thanks, Cap'nHook. <br />I am not gaining oil level in the pan through this whole thing, as far as I can tell, and I have been watching. However, I have only run it about an hour at a time before changing oil. Do you think that is long enough to show overfull on the stick? The water in oil is in pan as well as under filler caps. Dipstick clears after boat sits for a couple of days, but clouds after I run it for a half hour or so. Lifter? is noisy pretty much all the time, but not every piston stroke.<br />I did pull all the plugs at suggestion of friendly auto mechanic, but I'm not sure of what I found. Cylinders #3, #5, and #7 seemed a little oily or wet, but I'm not sure if it is a significant difference or not....not real dramatic. <br />I am really trying to get a handle on what is going on without spending more money on this just yet, because I have been thinking of using this drive train in yet another boat if it turns out I need a rebuild or long block. Don't want to put more $$ is this hull, but the drive train seemed really strong and tight until this happened. Am trying to decide do I part it out, repair and sell, sell as is, or repair/replace the engine and move to new hull.<br />I can buy long block for what shops want for rebuild if I have to go that far. Therefore the need to identify the problem at least cost. Am thinking about trying to do compression test myself. Is there anything particularly tricky about that? John