Zenith Float Bowl Vent Variations

[Thodge]

My guess you have an air lock or vapor lock until you get gas to flow. Oh yes good suggestion which reminds me of a couple of years ago using a float valve like the 3rd from left .... It's height created its own vapour lock ! Hopefully explained by attached pics

Johnbuckley was 100% correct with this diagnosis. Today I had the fuel level gauge on it. Opened the shutoff, nothing. Left it open for a while as I worked on another part of the car. Still nothing. Took the drain plug adapter for the gauge all the way out. Nothing. Loosened up the fuel strainer and fuel would leak out but when I tightened it back up, nothing. I remembered the air lock above the float valve suggestion so I gave a couple good raps on the front of the stainer cap with a wrench and the bowl filled up to 5/8” from the top almost instantly. If I hadn’t tapped on it, I’m pretty sure that thing could sit for a year and not fill the bowl. So the solution is either get a float valve with shorter threaded nipple or just hit it with a hammer.