There's a fuel dot between the tank and the check valve. This is the vent. The check valve allows air in during flight and the dot allows air out during fuelng. I'm assuming you know what a fuel dot is. It's nothing more than a plug in a fuel line. This system requires a Tee fitting between the tank and check valve or a 3rd line from the tank.

Time to head out to Busch Gardens with the kids for a relaxing day of fun. Oh Joy. If I'm not back in 2 days send in a search party.