Pressure in gas tank???

[Gordobe]

Hello hello,
When I go to fill up my fuel tank as I turn the gas gap a lot of pressure is released. Sometimes it even spits up gas. There also have been times when I'm traveling and close to empty that I fill up and a vacuum occurs which causes a lack of fuel to get to the fuel pump and it try's to stall out.
The check valve near the black devise at the tank appears ok and the charcoal canister line is not plugged. How do I know if the check valve is working correctly. Goofy issue
On mechanic thought that the fuel that I put is cold and causes a vacuum after I put the fuel cap back on.
Anyone got any thiughts

 

[Gordobe]

By the way this is a 55 I am referring to

 

[honk]

Check valve installed backwards?

I'd remove the valve and let the tank have a vent.

An old quick-fix is to drill a very small hole through the gas cap - small like 1/16" or smaller.

Buying a vented gas cap is another way that needs money be spent before experimenting and satisfying shade tree fixes can be applied.

Depends how you approach things.