Model B carburetor question

[Larryejoh]

I’m rebuilding a Model B carburetor that I acquired a while back. I noticed someone has driven a brass plug into the port in the casting at the throttle shaft. This port is supposed to open to atmosphere when at an idle and stop the power tube from drawing gas into the throat. The brass plug is not a factory one and was easy to pull out. Why would have someone plug this port? If I’m thinking correctly this would have enriched the mixture at an idle too instead of open throttle.

 

[ursus]

I have rebuilt a number of B carbs and seen some odd modifications, but never that particular one. Your supposition makes sense to me.