MikeG1955 "My question is should my valve cover hose be sucking in air or blowing it out ? It is blowing out a little blow by."
To answer your question as to whether your valve cover hose should be sucking in or blowing it out. The answer is yes. One or the other is happening at different engine loads.
A good indicator that this is true is that cars and trucks beginning in the '60s which all came with factory PCV systems had an open cell filter inside of the air cleaner at the end of hose that is the clean air supply for the PCV system.
This open cell filter would eventually be clogged up with crud from the crankcase.
One may wonder how, since the airflow should be in the opposite direction. Well it is during certain conditions, but goes in the opposite during other conditions.
