Fuel line question 78 datsun L20b

[Routsun]

There's 2 fuel lines that run parrallel and one goes to the fuel filter and where does the other one go?

[datzenmike]

You should have a fuel line to the engine and a return line to the tank if this is for an L20B.

 

Fuel is drawn from the tank through the filter into the pump. From the pump, under pressure, to the carburetor then back near the pump where there is a restriction. From here to the second, or return line, to the tank. Without the restriction the fuel would never build pressure and push into the carb, and would just return to the tank. The idea of the fuel return line is to constantly replace the fuel going past the carb so that it does not over heat and boil on hot days and cause hard re-starts.

 

Between the fuel pump and the carb should be a dual metal line. If this was removed, then some previous owner thought it looked 'neater' this way and has no idea what he was doing.

[Doctor510]

There's 2 fuel lines that run parrallel and one goes to the fuel filter and where does the other one go?

Would really help if you told us what vehicle the L20B was in.  Mike hit the info right, are we to guess it is a 620. 200sx, HL510, Subaru...