check valve draining oil tank on mercury 40.. I think

[Merc40fisher]

hey guys. I have a 2005 mercury 40 3 cylinder 2 stroke. Serial # 1B033613. When parked for a while my oil talk will drain completely dry into the motor and comes out everywhere. Iv read a lot on the check valves to prevent this but am unsure if I have the right one or if this will fix the problem. Heres the layout. line comes from the oil tank into the oil pump, from the pump into this brass check valve, from there to a plastic Y where it meets the fuel, then into the fuel pump and into the carbs. My question is what does this brass valve do and will this fix my problem? is it a one way check valve to prevent fuel from going into the oil system AND a 2psi valve to stop oil from draining under its own weight, or just one of those? and is this the O-SO-Talked about 2psi valve that will fix my problems? My understanding is that this is a one way valve to prevent fuel from entering the oil system and the oil pump has to pump atleast 2psi to push oil through. someone please correct me if im wrong. thanks a lot. If you google mercury 22-818994 then click on images. the first image is exactly the valve I have.

 

[Faztbullet]

Pull the pump as rear seal has popped out......If the check valve was bad it would :A) fill carbs with oil... B) Oil tank would swell up as not venting