Posted 1/5/2009 13:23 (#558410 - in reply to #558385) Subject: Re: C-12 Cat Fuel check valve?
Check valve would be in the fuel filter base. Depending on the serial # it could be in behind the fuel return line fitting going back to the tanks or it could be up on top of the base. This style takes a 1" wrench I believe. Give it a try.