I installed a 255LP Walbro Fuel Pump on my 2005 350z. And ever since then I’ve replaced the O Ring but it eventually starts leaking gas around the sides and it made sure I tightened it right so what can I do to seal it up good and I don’t get any leaks?

 

Found this article, not sure if you already followed this or not. But it appears some modification is required for a solid fit.
-Icer

 

I had seen that article a while back I ended up figuring out my issue my O Ring had pinched itself allowing fuel to leak out I used some adhesive to lay down the O Ring let it sit for a while then carefully put the fuel pump back in and screwed it down tightly and I haven’t had an issue since thankfully!