Carburator Choke Plunger

[jfmerk]

Does this small black seal need to seal off fuel? Or is it just a dust seal? It looks to me like the plunger is "choking" off air to the carb and therefore this seal may not see any fuel. As I start digging into the carbs while I wait for engine parts I noticed that there isn't much tension between this seal and the shaft and if it needed to seal off fuel it would be a certain leak. Can anyone clarify this?

[DiverRay]

That is a "dust" seal. It does NOT need to seal off fuel. The fuel seals against a rubber bit on the end of the plunger when off, and is allowed to "flow" into the airstream via the carb throat.