[flatheadron]

A quick check to make is to remove the breather cap and rig a vacuum gauge in the opening. Should be some vacuum there. Do not remember how much but some. Used to be a small plastic gauge in the old days you held over the pipe and it registered a vacuum or pressure. System works by drawing in clean air through the breather, circulating it around the engine and out the PCV valve which meters the flow. Sounds like it is blocked somewhere. Y-blocks had two styles of road draft tubes. One on the front left of the block with a filter/oil separator, the other at the back of the valley pan. Both were baffled to prevent oil from being sucked out. Which style was yours originally? I don't like the location your valve is installed in. Hard to tell what the tapped hole was originally used for. But I see another picture showing it in the valley pan. Which is correct now? Rather see it in the valley pan, but has to be baffled.