Starting to get water in oil.

[lonewolf41]

My "new" boat had been sitting for the last 6 years. It has the 1998 4-cylinder 30GSMBY Volvo in it (picture of tag attached). I've got it running now but am still leery of it until I get a few trips under my belt. Took it out for a couple of hours last weekend and it ran good. Checked the oil after and it looked good, a little darker after running for a while, but still nice and honey colored. Took it out again today and after an hour or so, we came in due to another issue. I checked the oil and it looked milky (picture attached).

I thought that it might be the exhaust manifold/system so I took it off and you can see what I found. It looks like rust on the wall and water sitting in the exhaust side of the manifold. I attached pictures of both part surfaces. I am assuming that water is going into the exhaust at the riser connection and then sitting in the exhaust port(s) eventually leaking past the valve, piston, and then into the oil. Does this seem like the most likely scenario based on the evidence? Any other things/areas to check?

TIA,
-Keith

 

[aerobat]

Re: Starting to get water in oil.

does the engine has any running issues or does it run fine ?

 

[Scott Danforth]

Re: Starting to get water in oil.

I would also pressure test your block. however it looks like you may have found at least one issue

 

[lonewolf41]

Re: Starting to get water in oil.

does the engine has any running issues or does it run fine ?

It actually seems to run fine. I even pulled a skier with it before we came in. It died on me one time yesterday while idling. I wasn't sure if that was due to incorrect idle speed or now wondering if maybe it took in a gulp of water. It took a couple tries to start back up, but it did. Also not sure if I have the carb tuned correctly yet after the rebuild. Other than dying on me once, you would not know there was anything wrong.

 

[lonewolf41]

Re: Starting to get water in oil.

I would also pressure test your block. however it looks like you may have found at least one issue

I did not see a procedure for this in the manual. Is there a preferred method for doing this? Also, does anyone think that removing the head would gain me anything worth the effort? I may go ahead and remove the manifold so I can clean it up good and get good sealing surfaces, but have been debating on the head itself.

Thanks,
-Keith

 

[Scott Danforth]

Re: Starting to get water in oil.

Here is a thread regarding pressure testing a 3.0

you should pressure test first, as well as a leak down test. this will identify if you have a problem past the exhaust manifold and riser.

 

[lonewolf41]

Re: Starting to get water in oil.

Here is a thread regarding pressure testing a 3.0

Was there supposed to be a link somewhere? I did a search and found some info on manifold testing, but nothing on the block. Assume it is pretty straight-forward, but just wondered if there were any shortcuts or gotchas that would be handy or needed to know.


Thanks again for the assistance,
-Keith

 

[lonewolf41]

Re: Starting to get water in oil.

Actually, I can probably figure it out. now that I think about it, it should be pretty easy. Does the manual list a test pressure or what pressure should it hold and for how long?

Thanks again,
-Keith