Excessive suction in fuel tank

[nailbender63]

The fuel tank on my 24 Ridge XR sucks in do to suction in the tank which releases and expands once the fuel cap is opened, this has actually torn the body panel in two directions surrounding the filler neck has anyone else experienced this problem?

 

[nailbender63]

Photos with cap on and off.

 

[Montana Mountain Family]

It sounds like the vent is either plugged or if it has a check valve in line in the vent line it maybe stuck unplug your vent line and see if it still does if it does then check the nipple where that vent line was hooked up and make sure it's clear