Oil in Bilge

[GaBoy]

This is a mystery to me. 2 weeks ago I pulled my 26 ' Searay Merc Gm 350/260hp 35 miles for storage. The week before I had ran the engine using muffs at max rpm of 1000 for 5 minutes just to test cranking and warming up. Raised stern and fastened down for move to storage. Checked oil and very clean after changing 2 weeks ago. Added fluid to stern drive motor pump and all was well. Pulled boat to storage and I put a cover on. I left the stern up. I went by today and was checking engine area and noticed about 3 pints of liguid in bilge. Checked and it was oil looking and feeling. Pulled dip stick and oil looked milky. Water in oil but over full on stick. Checked the oil filter and not oily or wet. Checked fluid line on stern motor and no leak or oil. What's up? I am planning on checking oil asap and filter and look for more leaks.

 

[Don S]

Re: Oil in Bilge

Water getting into the oil, will not make the oil milky UNLESS the engine is running. The oil pump is what mixes the two.
I have seen people just pull the dipstick check the oil. That is not the way to do it. You need to pull the dipstick wipe it off and redip to get an accurate reading of what is in the engine.

The oil could be anything, the ONLY thing you can do is wipe everything off clean, run the engine, pumps, outdrive, and see what is leaking, no way can anyone guess what it is without doing so. They can tell you where theirs leaked in the past, but not where yours is leaking.

Also, what year is this Merc 350, what drive? what color was the oil that leaked? Brown could be engine oil, green could be gear lube, red, ATF.

 

[GaBoy]

Re: Oil in Bilge

The boat is 1982 and the engine I assume is the same year. The oil in the bilige looked brand new with no milky discoloration and it was the honey color of oil. Someone told me that you should not store a boat with the stern drive up that stern fluids and water could leak back to engine. The engine runs great and has never overheated in the 4 months I have owned it. Possibly I have a head gasket blown or holes in exhaust chambers, who knows???

The first time I changed the oil I noticed when pumping out a little milky appearance but right before changing the oil my bilge pump had stopped and the engine compartment was flooded to the starter.

But since then no milky look to oil at all unitl I moved to storage. I wonder if when I bought the boat the previous owner knew about this. I can only say that the boat runs so good I am amazed. Have not noticed any steam or oil leaking in any other location.

I will fix the problem and go on. Where do I go from here? Start checking the heads? I did put the stern down yesterday and wiped up all the fluid or oil in the bilge area.

Thanks

 

[Don S]

Re: Oil in Bilge

Someone told me that you should not store a boat with the stern drive up that stern fluids and water could leak back to engine.

Nope, the reason is to save the bellows and keep water from sitting in the exhaust housing and cracking the housing if it freezes. Being up won't cause any oil leaks.

I would start by draining all the water out of the engine, isolating the block and pressure check it to see if it will hold about 15 psi of air. It should.
Also check the manifold, risers, and manifold/riser gasket surface for damage.

 

[GaBoy]

Re: Oil in Bilge

Thanks Don S and will let you know what I find.

 

[f_inscreenname]

Re: Oil in Bilge

Before going crazy check your trim lines for the leak. You never know.