Suzuki anti-siphon valve

[triumph190]

I have a 140hp suzuki 4-stroke and I think my anti-siphon valve may be bad. I can pump the primer bulb and nothing happens. After replacing the primer bulb I tried pumping fuel into a bucket, but nothing would come out. I took the anti-siphon valve loose from the gas line. Then I took it off the gas tank and tried blowing through it as hard as I could but got very little air to come out.

Does this sound like my anti-siphon valve is not working correctly and/or needs to be replaced?

Do I have to have the anti-siphon valve?