Wagoneer L6-258 4.2L VIN C 2-bbl (1982)
Carburetor Float: Description and Operation
Fig 32 Bowl Vapor Vent
Fig. 33 Carburetor Bowl Vent
This vent, Fig. 32 & 33, used on some carburetors, provides an outlet for fuel vapors when the engine is not running. If this vent was not provided,
raw fuel vapors would enter the atmosphere. Some vapors would also enter the intake manifold making hot restarts difficult.
When the engine is running, the fuel bowl must be vented to the inside of the air cleaner for proper fuel flow. This is accomplished by
automatically closing the bowl vent. Some carburetors use manifold vacuum to accomplish this while others use a mechanical link to the throttle.