PCV on 8BA

[Flathead Fever]

Don't think it's "extremely" important for preventing oil from turning into sludge.
It would do that even if left wide open.
It is extremely important to prevent any backfire from blowing your engine apart while igniting crankcase gasses.

Plugged PCV system. In the article below a working PCV system looks "extremely" important to me. A lot of it depends on how often you change your oil. How much blow-by the engine has. Short driving trips. You have detergent oils now that you did not have back then. PCV systems and modern detergent oils are why engines now last 250K miles instead of 50K to 100K.

http://www.agcoauto.com/content/news/p2_articleid/197

 

[Robert Legner]

I tested the PCV valve today and found the valve is sticking open. I stopped the vacuum with my thumb and then unstopped the vacuum and the vacuum went from 18 inches to 16 inches. I turned the car off and restarted and the vacuum was down to 5 inches, covered the opening with my thumb and then removed my thumb and the vacuum stayed at 16 inches. So I think the valve is sticking, is faulty. I wrote to the vendor and asked for a replacement valve. When I get the replacement valve I will test it and write again. Thank you all for your input!

 

[51 MERC-CT]

I tested the PCV valve today and found the valve is sticking open. I stopped the vacuum with my thumb and then unstopped the vacuum and the vacuum went from 18 inches to 16 inches. I turned the car off and restarted and the vacuum was down to 5 inches, covered the opening with my thumb and then removed my thumb and the vacuum stayed at 16 inches. So I think the valve is sticking, is faulty. I wrote to the vendor and asked for a replacement valve. When I get the replacement valve I will test it and write again. Thank you all for your input!

Suspect that you are over thinking the operation of the PCV valve.
Forget about applying vacuum readings to the operation of the valve.
With the engine running the valve will be OPEN to one degree or another.
The only time it is designed to close is in the event of a backfire to prevent a flame path to the crankcase.