3.0l Mercury Oil Leak

[firminator_x]

I have a 2003 Sea Ray 176 with a Mercury 3.0l and Alpha 1 outdrive. I took the boat out for the first time yesterday for about 5 hours.

I have noticed that I have a small oil leak coming out of the top of the valve cover where there is what looks to be a PVC valve. The oil is seaping around the rubber boot is sits in. I also noticed that the oil is being carried though a plastic tube up to the aircleaner. This is my first boat but I know oil leaks aren't good!

Any help is greatly appreciated.

 

[firminator_x]

Re: 3.0l Mercury Oil Leak

The more I think of this, maybe that oil is coming out of the pvc valve (or what I think is the pvc valve) and dripping back down on the valve cover. There is also a bit of oil at the air intake.

I am starting to think that I might have been sold a boat that needs more attention that I realized. I also have a different link about the drive gear oil being used....

 

[Blujay96]

Re: 3.0l Mercury Oil Leak

Sounds like blow by. My 1987 3.0 has the same. I was told as long as it was not to much there was not much to do for it but a complete rebuild.

 

[Don S]

Re: 3.0l Mercury Oil Leak

Can you post a picture of the oil leak area. From your discription, it's hard to determine how much oil is there. It could be normal or may some spray corrosion guard oil sprayed on your engine to prevent corrosion.

 

[firminator_x]

Re: 3.0l Mercury Oil Leak

Don,
I cleaned up and it is engine oil.

It is the line that comes out of the top of the valve cover and connects to the air intake. It isn't a pcv valve, it's just a plastic elbow coming out of the top of the valve cover. Then there is some plastic flexable tube that runs up to the air intake.

 

[firminator_x]

Re: 3.0l Mercury Oil Leak

It's the line coming off the left side of the intake. see pic

 

[firminator_x]

Re: 3.0l Mercury Oil Leak

I think it is called the CCV tube.

 

[JustJason]

Re: 3.0l Mercury Oil Leak

Doesn't mater what you call it, it's a crankcase breather pure and simple. If you have oil comming up through that you are way overfilled with oil, your adding to your oil level with either water or gas, or you have some seriously blowby going on.

Check the oil level first, if it's really high pump it out and see if it's water or if it's fuel in the oil.

If it's not high, do a compression test and report back with your numbers.

 

[firminator_x]

Re: 3.0l Mercury Oil Leak

Oil level is fine. At the full mark on the dipstick; looks and smells like oil.