94' 7.3 IDI turbo Fuel Problems

[Stephen]

Im having troubles with fuel pickup. From a full tank to half it runs great. From half to a quarter it hesitates, lacks power and stalls. when down to a quarter it will shut down completely. After sitting it will crank to prime and refire for a while then shut off. I have replaced the primer pump. changed filters, and checked lines for leaks. I am thinking there are problems in the tank. Never gone into the tank before. Am I on the right course or off base. NEED HELP! Thanks.

 

[SuperCab]

My first thought is maybe a hole in the pickup tube in the tank that's letting it suck air?

 

[Fellro]

The diesel trucks of this age have an annoying plastic sump that has a tendency to break off. They key detail you give is that at 1/4 tank, you are dead in the water. That is about the level the sump hooks up at. You will need to pull the fuel sender to fix this issue. What I and many others have done is add a piece of hose or such in lieu of the original sump.