I think you are referring to the crankcase vent pipe. Before the EPA got involved, all cars vented their crankcase fumes right out into the air. Then PCV came along, and now we feed the fumes back into the engine to be burned in the cylinders (much more environmentally friendly)

If you are pumping oil out of this, the rings are probably shot, or some part of the baffling system is not there or working properly.

Could be something else, but that is one thought.

Don