Rear Fuel Filter Cap issues

[MAD6601]

Replaced the fuel filters on my 2022 2500 diesel and for some reason I have a slow leak at the bleed valve on the rear fuel filter cap. Thought I had it tight enough but it started spewing fuel when the fuel pumps kicked in. I had the yellow witness marks lined up. I tightened the valve more and that seemed to fix it but it has established a slow leak. Anyone had this issue?

 

[red]

Un-screw the drain valve completely. There's a small o-ring that probably picked up some dirt. Clean the ring, lube with engine oil and put it back together. If it still leaks get a new o-ring.