Agreed, While the engine is running pull the PCV hose off the carb. Engine RPM should increase or possibly kill the engine. Put hose back on and start engine again. This time disconnect the hose at the PCV valve. Engine should do the same thing. I guess the PCV hose could also be collapsing. Double check the entire PCV system. If all is good you have ring problems. Maybe just take it out and
Rings could be gummed up and letting a lot of blowby by.