I have a 700h if it sits for more than 10 minutes shut off you can't start it without putting fuel in the filter. I guess I would call it losing it's prime. Take filter off it's almost empty. I've put ew filters filter base lift pump and a new inu
If the filters are empty, that means they cant fill back up.. There is a blockage from the fuel tank TO the filters.. probably a rusted fuel tank.?? Its also possible the lift pump is broken too.. Try removing the fuel tank cap while diagnosing.. & if its metal, look underneath it & see if its rusted.. IF SO, THATS a good indicator of the condition of the tank.. You "could" remove the line at the filter head, remove the tank cap & using compressed air, blow back to the tank, unclogging it..
The fuel line grommets are always an issue with this engine. Check them all but especially any metal lines on the suction side like from the fuel filter housing to the supply pump. Also there is a plastic bleed screw on the filter housing and there is an oring to check there and also one in the top, but I believe you stated you addressed the fuel filter housing. It is just like sucking liquid up in a straw and holding your finger over it to hold the liquid in the straw, let air in and the liquid drains out. Find the where the air is going in and you will have it fixed.
Had the same problem with a jd 444j ,pervious owners changed everything. We bought it changed fuel line gommets on the suction side. Haven,t had a problem since.