Long story short .... Recently purchased an old ford diesel
was running fine but the seller has added a 3rd fuel tank and said he has the truck running only on rear tank well... my tank switches got messed with and ran out of fuel and back tank would not work so I by passed to the extra fuel tank in the bed of truck ..... running those fuel lines directly into the main fuel lines and by passing all tank selectors and levors......
I also changed fuel filter and fuel injector line was leaking so ireplaced that... i'm just not getting fuel to fuel filter....
also 2 lines going to engine one is input one is return stacked on top of each other along frame have tried both the smaller is input and the larger is return???? I am thinking of replacing fuel pump next it is chap and seems easy to replace??? any help would be appreciated.........


Thank you Bruce Newbauer

 

I agree. Go with the fuel pump first.

Les

 

I believe that the Larger of the lines is the SUPPLY line, and the smaller is the RETURN line. The engine requires more fuel to it than it returns to the tanks. The fuel returning to the tank is the leakoff from the injectors and the air bleed from the top of the line running to the injection pump from the filter head.

If it ran before the tank went dry, and now that you have had to play with the lines, I would suspect the fuel supply hookup before the pump.

STAX
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