Mercruiser 93' 3.0 milky oil

[regal17]

Hello guys I'm new to this site but had found lots of useful info from searching on here so Id figure someone might have answers to my current issue.

I have a 3.0 mercruiser in a 176 regal and I began seeing milky oil last week. I first thought it was a cracked block because all threads have pointed that way so I ran the pressure check on the block and have no leaks holding pressure good. I saw when running a small leak from the exaust manifold where the gasket sits while running. I have also re ad about intake mani leaking and causing water in oil. If anybody has had this issue without a cracked block I would just like to know what direction I should go for next..head gasket? replace manifolds?. Or any test to pin point exactly where it is before just throwing money at the motor. thanks for the help in advance!!!!

 

[Don S]

Re: Mercruiser 93' 3.0 milky oil

How much water in the oil we talking about? Is the level over filled? or are you just seeing condensation in the valve cover.

When you did the pressure check on the block, did you drain the water first?

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

first time i pressure checked it it had water in it. pressure checked good. then I drained it and did it again and it pressure checked good. the level does not seem to be rising but the oil is milkshake color.

 

[Howard Sterndrive]

Re: Mercruiser 93' 3.0 milky oil

if not the block, probably the exhaust manifold - remove it and look for water/rust streaks in the ports - You should only see dry soot in the ports.

Only after the block and manifold are 100% eliminated would I think about head gasket.

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

I did the pressure check correctly. block is holding the pressure put through the cooling system. maybe intake manifold gasket? i hear this is common?

 

[Don S]

Re: Mercruiser 93' 3.0 milky oil

The intake manifold gasket is not a common problem, and can not cause water in the oil. Not sure where you are "Hearing" all this stuff, but it's not true.

Exhaust riser gaskets, or faulty exhaust manifold or riser will get water in the cylinders, but you would have notice a hydrolock had that been the cause, plus the exhaust when it's running blows the water out.

Have a look at this service bulletin, it may help explain things.

View attachment Water Intrusion 01-13.pdf

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

So I should check the intake manifold for possible cracks? At this point the block is out of the question due to the fact of holding 15psi for good amount of time. Whats the best way to check intake manifolds?

 

[Bondo]

Re: Mercruiser 93' 3.0 milky oil

So I should check the intake manifold for possible cracks? At this point the block is out of the question due to the fact of holding 15psi for good amount of time. Whats the best way to check intake manifolds?

Welcome Aboard,... Nope,.... Ya need to check the Exhaust manifold, right where it meets the exhaust Riser...

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

I removed the exhaust elbow where the leak was and found no gasket just a lot of brown looking sealant. I will be putting a gasket in this week hopefully after work. My question now is could this be my problem or can I leave the intake and exhaust out of this equation because I do not experience a hydrolock situation?? How would water get past my rings? Correct me if I'm wrong just a little confused here.
Thanks in advance!!

 

[Howard Sterndrive]

Re: Mercruiser 93' 3.0 milky oil

How would water get past my rings?

actually, rings do not seal very well- they have something called "end gap"- gallons of water can run right through unrestricted as long as it does it slowly.(i.e. - a bit each time the engine is shut off after a run)
You need a proper riser gasket. I'm surprised it ever even ran with just sealant. You got lucky finding it this way... that could have destroyed the engine.

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

Yes good thing I caught it. I had just changed the oil in it too and only ran it for about twenty mins shut it off and all oil was then light white milkshake. I'm hoping an oil change with filter and installing the gasket will correct my milkshake problem. I was not aware that water could skip by the rings like that. Thanks for the insight.

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

Well i replaced the gasket put a lot of perfect seal along with it. drained the oil out and filled her back up with new and a new filter. seems like traces are still in but not nearly as much as before. I'm assuming that the oil that was in there before has left a little behind?

 

[Bondo]

Re: Mercruiser 93' 3.0 milky oil

Well i replaced the gasket put a lot of perfect seal along with it. drained the oil out and filled her back up with new and a new filter. seems like traces are still in but not nearly as much as before. I'm assuming that the oil that was in there before has left a little behind?

Ayuh,.... There's always abit left, as well as condensation....

A good hard run will usually steam it off...

Keep an eye on the oil Level,...
It's a better more meaningful indicator, than color...
Risin' level is Bad,...

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

Alright guys I have an update again. I am on the second oil change now with new filter. I still see cloud under valve cover cap and a very clear dipstick almost unable to read! still seem like it is not rising. how many oil chages do i need to do? or whats going on?

 

[regal17]

Re: Mercruiser 93' 3.0 milky oil

also I have no temp reading anymore would this have anything to do with my issue??