[nkaminar]

I believe that is a Tillotson carburetor. They were an aftermarket carburetor available for Model A. They are reputed to be better performing than the original Zenith. The problem with them is that they are make of pot metal and warp over the years, especially the flange that attaches to the intake manifold if the bolts are over tightened. You can tell if there is a vacuum leak by spraying some WD-40 at the flange to see if the engine speed changes. If it does then there is a leak.

If you are having problems with the carburetor, take it apart and clean it out with carburetor cleaner and compressed air. You don't have to take everything apart, just separate the halves. If you feel like you are not capable of this, get someone to help. Gasket sets are available from the vendors and there are people who will rebuild it for you for a price.