Milky engine oil not sure why

[srocc]

While winterizing engine, I drained the oil and it was very milky. I took it in, they pressure tested and ran for 45 minutes. Everything tested fine and the oil had no water in it. Any thoughts? I trailer the boat and it never sees the rain. Ran fine the entire season. Also when I changed the oil the level wasn't high

 

[Don S]

Re: Milky engine oil not sure why

What engine?

Here is a Mercruiser service bulletin on water intrusion.

 

[peejcj8]

Re: Milky engine oil not sure why

Awesome document! Thanks Mr Don. Hope to never need it!

 

[ziggy]

Re: Milky engine oil not sure why

Hope to never need it

me too. but, i've needed it twice.
once for the boat. once for the van. fwiw, the boat was in need of manifold and riser, the van is a intake manifold leak that sucked the coolant right out of the cooling system into the oil.
while that whole sb is great, the very fist statement is the real winner imho. FIRST, SAVE THE ENGINE. #1, change the engine oil and filter. i did that on both my woes and saved both engines too. both still in service.

 

[srocc]

Re: Milky engine oil not sure why

2002 mercruiser stern drive, carbureted.

 

[Don S]

Re: Milky engine oil not sure why

2002 mercruiser stern drive, carbureted.

Ok, now we are getting somewhere. :facepalm:

What kind of engine is your 02 carb setting on? I4, V6, V8 if a V8, which size, and what kind of Mercruiser outdrive?

 

[Bondo]

Re: Milky engine oil not sure why

While winterizing engine, I drained the oil and it was very milky. I took it in, they pressure tested and ran for 45 minutes. Everything tested fine and the oil had no water in it. Any thoughts? I trailer the boat and it never sees the rain. Ran fine the entire season. Also when I changed the oil the level wasn't high

Ayuh,.... How much over-full was it before ya pulled the plug,..??
How much liquid did ya drain out,..??

 

[srocc]

Re: Milky engine oil not sure why

It's a 4.3 v6 with a gen + outdrive. I drained the oil and never checked thelevel, but judging from what came out there didn't seem to be much extra in the pan.

 

[Don S]

Re: Milky engine oil not sure why

Have you done a lot of starting the engine, running for a few minutes then shutting it off? Without actually taking the boat out for a good run to really warm it up?

It's a 4.3 v6 with a gen + outdrive

Just an FYI
That's probably a 4.3 V6 Gen+ engine. The drive would be an Alpha I Gen II or a Bravo I, II, or III. There are no Gen+ outdrives

 

[srocc]

Re: Milky engine oil not sure why

Gen II outdrive. Usually take it out and bring it to temperature. Out for a few hours at a time. Same pattern as the last few years and I never had this issue.

 

[Don S]

Re: Milky engine oil not sure why

Do you know if the shop that did the pressure test on the cooling system drained the system first? If they didn't, even with a small leak, it wouldn't show a noticeable pressure drop until the water was gone.

 

[srocc]

Re: Milky engine oil not sure why

I'm not sure.

 

[Leedanger]

Re: Milky engine oil not sure why

I don't what to pull away from the topic, looks like your starting to make progress, but if I remember right that service bulletin doesn't mention the U-joint bellows. I haven't read it for a while so if it does ignore me please....if not it's something to consider.

 

[Don S]

Re: Milky engine oil not sure why

There is no way that a leaky bellows can cause water to get into the engine oil ......................... Unless the boat sinks.

 

[Bondo]

Re: Milky engine oil not sure why

It's a 4.3 v6 with a gen + outdrive. I drained the oil and never checked thelevel, but judging from what came out there didn't seem to be much extra in the pan.

Ayuh,... I'm thinkin' you were seein' condensation, 'n nothing more...

 

[srocc]

Re: Milky engine oil not sure why

Thanks Don and everyone else who replied.