if that is the gasket , or whats left of it theres your problem , they push air not fuel into the float bowl so need to be sealed / gasket in good nick , i have made them before and worked well , depends on how far away your parts shop is . new gasket and it should work , or as super d said , could be primer bulb but while its off new gasket and see how you go .
hope it works out for you . simple fix sometimes hard to find
