chocolate milk for oil

[chum bucket]

I purchased a 140hp 3.0 and checked the dipstick before purchase. At the time I did not see that the color of the oil was infact like chocolate milk w/no bubbles. This was realized after draining oil for a change.
Before the purchase I also checked the compression of the cyl.
#1-115 psi
#2-110 psi
#3-126 psi
#4-140 psi
I am trying to trouble shoot where the problem is from the color of the oil. I am pretty sure water is getting in to the oil. What is the line of progression to find out where it is comming from, ie, Manifold or Block.
I continued on with the oil change but have not run yet. The boat was sitting for several years, could enouph condensation have formed to taint the oil?
Before draining the oil I did run breifly without water intake to see if it would start. It did, I suppose this could have mixed up the oil to make it look like chocolate milk. This maybe the reason I did not see it on the inspection of the dipstick.
Thanks Jake

 

[Howard Sterndrive]

Re: chocolate milk for oil

oil floats on water, so when a block cracks from freezing, the water sinks. The dipstick will look clean and clear. Once you start it up, the water and oil emulsify into the milk.

Step 1. Crank your head upside down with a BRIGHT trouble light and look under the manifold along the port side of the block., Look for a crack and rust streaks along the block just below the line where block and head meet.

I've never seen a 3.0 crack internally that didn't also crack externally. And port side under the manifold is the favourite place for cracking.

If you see cracks, you need an engine.

No cracks, move to step 2:

Step 2. Pressure test the cooling system and listen for leaks.

 

[mark1905]

Re: chocolate milk for oil

Before draining the oil I did run breifly without water intake to see if it would start.

Meaning.. you just started the motor while it sat on the trailer.. No hose muffs, no nothing? How long did you run it like that for?

 

[chum bucket]

Re: chocolate milk for oil

Ran on the trailer w/ no hose for 10- 15 seconds to see if it would start not long enough to damage

 

[Howard Sterndrive]

Re: chocolate milk for oil

should mention also - do not disassemble the engine until you diagnose the issue.

So many people on these boards start ripping into motors without doing the diagnostics first. Once you tear the head off, you have nothing to go on.

 

[mark1905]

Re: chocolate milk for oil

Ran on the trailer w/ no hose for 10- 15 seconds to see if it would start not long enough to damage

That's long enough. Even 5-10 seconds is enough to score the sides of the impeller casing. I know that's the least of your worries now, but it is now yet another issue..