I'm a little late coming into the conversation, this carb. (UN2), is produced primarily for the S. American market. A lot of old cars which the original Rochester "B" will work on are there. Cuba has them on everything! Like the song by Jackson Brown " you can see a Soviet transmission in a Chevrolet". I'm a Rochester model "B" fan(atic), the reason that ClassicsR4Me is having trouble with the gas drain is one of 3 reasons: leak in fuel bowl to air horn gaskt., fuel line leak at carb or the Throttle body shaft. These old carbs can only be rebuilt so many times and beginners have a tendency to warp the air horn. A whole big bunch of thanks to Classics R4Me, great job and very attentive to his testing and follow up.
