Intake manifold Not seating properly (?)

On my small block LA 360 after removing and replacing the intake manifold I used a bead of RTV at the front and rear end rails like you are recommending. I am getting some oil seeping out of this area at the front of the motor. Maybe I did not use enough RTV in that area? Or could this also be a sign of a clogged up PCV valve allowing pressure to build up in the block?