Norgren Regulator Leaking from Vent

[Car Wash Man]

I cleaned the filter on my Norgren regulator today in the carwash room and now there is a constant slight air leak from the vent on the bottom of the regulator where the filter side is. I took everything back apart and reinstalled multiple times and cleaned it to make sure there was no debris but I cant get it to stop. Any ideas?

 

[Keno]

does it use an o-ring to seal? is whatever seal it uses in good shape?

 

[Car Wash Man]

Nothing looks to be damaged upon taking apart and inspecting. I'm guessing air is getting through some seal though due to age.