in which the link maintains the lever 110 in the position shown to lock the end of the actuating lever 60 in the position shown in fig1 and 8 during this passage of fluid through the housing 10 vapor from the vehicle tank is forced through the annular space 34 between the sleeve 22 and the spout 20 as a result the vapor passes through the passage 36 in the manner described above before exiting out the vapor outlet 12 and through a suitable hose for passage back into the storage tank or the like for further treatment as soon as the level of the gasoline in the tank to be filled extends over the opening 32 in the spout 20 as shown in fig9 the vacuum in passages 80 82 and 84 is no longer relieved and is sufficient to overcome the force of the spring 100 so that the membrane 90 and therefore the link 102 moves under the force of the spring 52 acting through the lever 60 to a position shown in fig1 i e in which it no longer engages the locking lever 110 thus the lever 110 rocks about its pin 112 under the force of the lever 60 out of a locking engagement with the subhousing 66 as.