Fuel pump diaphragm

[Williampardell]

I'm replacing the fuel pump on my 40 HP merc. The old one has a plug in the front where new one has a nipple for a hose. Is this a vent of somekind

 

[faztbullet]

Did you order the correct pump as it should be a 14360A73.. The some newer motors use dual pulse thru that port or it can be used as a oil feed depending on internal body/diaphragm