I've had some oil in my bilge the last couple of times I've run the boat. It appears to be comming from a brass thing screwed into the block and another upside down under the valve cover. The only other thing I see that is brass is the drain plug adapter to drain the oil. I tightened it up about 4 turns hopefully this will stop it. Is this some kind of aftermarked device? I have a 3.0 OMC 1990;<br /><br />Thanks.<br />Mike