I have a USA rebuilt made in America double action Y block fuel pump I am preparing to install. I do not use the upper section for the windshield wiper motor and that section has a vented hose between the steel tubes. My question whether or not you need the body breather hole when you have a PCV system installed. I believe the hole goes into the section where the arm to the actuator on the camshaft is and technically the internal crankcase which would be a suction leak to the system. What are your thoughts.
I ask because none of the 70-80’s mechanical pumps I’ve installed on other engines don’t have a breather hole.