Part ID Questions for a tiny little valve? on the crankshaft cover on Mercury 150 v6

[snowbrd84]

I looked at all the diagrams and searched far and wide on the web. I am rebuilding my 86' Mercury 150 v6 that blew the #6 piston. On the crankshaft cover, there is what appears to be a very small gray metal ball sitting in a brass valve/fitting that is pressed into the crankshaft cover. It is located at the lower end on the outside of the crankcase, behind the fitting a small passage goes through the crankshaft cover to race that the crankshaft counter weight rotates in. I am just generally curious what this is, is it some kind of blow off valve? It does not show up anywhere in the manual or on exploded parts diagrams. blowing compressed air from the inside, some air pushes past the ball... Anyone know what it is/does?

 

[CharlieB]

Re: Part ID Questions for a tiny little valve? on the crankshaft cover on Mercury 150

The re-circ system uses these small fittings, some with one-way check valves, to remove accumulated fuel/oil from collection areas and reintroduce it into the intake air so it can be burned.

You may have broken one of these off and can see the check ball inside.

You should also find a small black hose hanging one end loose with the nipple portion of that fitting in it.

Have your model and serial #'s handy and look up the parts using pictures

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