Fuel Pump Cap O-Ring Help

[jspaeth]

Hey, I posted a few days ago about leaking gas.....

Went to Nissan, bought a new O-ring that goes in between the fuel pump and the screw on cap that holds it in place....

Please answer only if you are sure...

The question is....looking at the o-ring from the side, it has a "top lip" and an intermediate lip....when I put it on, it seems to want to settle on the intermeditate lip, i.e. it doesn't go all the way down the to the top lip....

Is the correct.....also, how tight should i be making the top lid piece that screws on top.....I am afraid that maybe it was overtightened before, causing the seal underneath to rip maybe. Given that I don't have the "tool" (one of the famous Nissan phantom tools found in FSM), I just made it hand tight and then tapped it tighter using a putty knife up against the edge with a light tap


Anyone that can enlighten me thanks