engine cuts out when going downhill

[blckwlfny1]

I have a CNS carb. It runs fine on level Ground or going uphill, but going down hill, the engine cuts out. There's fuel in the line. When I went to check the bowl, very little fuel cam outn but bubbles appeared in the line. I closed the drain screw and the engine started right up. ...only to repeat the problem on the next downhill run
Gas tank vent is clear
Forward lean of carburetor is about 17 degrees up from horizontal
Is this a float problem or a vent problem?...or something else?

 

[GearNut]

That is a pretty steep angle for the carburetor to be at. They are designed for the fuel to sit level in relation to the bowl gasket surface. At that angle it is at right now, going down hill may cause the fuel to go past the odd angle that the carburetor can withstand.

 

[blckwlfny1]

...Turns out the problem. Is the long worksman gas lank and the fuel all goes away from the petcock. When facing down hill...duh!
Thanks