fuel pump weakness

[bahmi]

I've got a diesel Oliver and the fuel pump appears to be working OK. Still, after I connect the fuel line after the pump to the fuel filter, I get no fuel down near the entry point on the injector pump. Does a fuel pump work when the engine is not turning? The fuel tank is above the pump and creates what appears to be an adequate pressure head to push fuel through the fuel filter down toward the injector pump. I blew out all lines, threaded a multi-filament wire up through the feed line from just before the injector pump up to the outlet of the fuel filter. All lines appear wide open and clean.

What am I missing in determining why I am getting no fuel delivery? Will gravity alone push fuel through the system so I get drainage just before the injector pump when disconnected? All systems seem OK, but I just wonder if the diaphragm in the pump is flaccid and not putting out enough head to push fuel adequately.

 

[jasinpa]

what model are you working on ? i know some of the 310 engines 17 - 18 -1955 , had lift pump from new , but were changed over to just gravity feed to the injection pump like my 1855 is , but you need to use the fuel filter that will let it flow with gravity ,and i believe the fuel filter was moved up higher on the side of block , if you have a good filter on there and crack the line feeding the injection pump , you should get fuel when cranking engine if tested would be around 3 psi , i think the lift pump is lower then injection pump so no fuel will get to injection pump without cranking or running engine , let us know model & what filter set up you have