Hi. I wanted to check with you guys before I break this little plastic knob on the bottom of my Racor 500 bowl. I need to open it and drain some dirty fuel. It looks like it simply unscrews but I wanted to be sure. It does not feel like it unscrews as it has sort of a rubbery feel to it and wants to pop back in place when you turn it. Looked up the users manual but it only said "open the drain on the bottom of the bowl"
ha ha.