What is this thing

[Kevin.clark]

Just bought a 1996 150 offshore Mercury. What is the port shown in the attached picture, and what should or should not be coming out of it. Water, exhaust, or nothing.

 

[Chris1956]

Re: What is this thing

Does that motor have two ports, one of which is plugged? If so, one is telltale and the other is for flushing the motor after use or while testing.

 

[Kevin.clark]

Re: What is this thing

It does have two ports and one is plugged, but what I am trying to show in the picture is a port below the tell tale.

I think my question was answered in another thread though. Someone mentioned it is probably an exhaust relief during idle.