Where does hard fuel return line run to?

[antiextreme]

Where does the hard fuel return line run to? My l18 620 has the hard line running to the inlet on the carb. Before it hits the carb there is a T in the line where a hard line is run back to the location of the mechanical fuel pump, where the previous owner capped it off. I'm hooking up a Weber 32/36 and would still like to have a return line. Does that return line eventually run all the way back to the tank? Is there another hard line in the frame on the passenger line that it should attach to?

 

I've scoured the posts and have found most of the info I'm looking for, but can't find this exact bit.

 

Thanks y'all!

[datsunaholic]

'74s didn't have a standard return line on the passenger side like the 75+ ones.  There is a tank vent (evaporative) one on the driver's side that can be used IF the system is still sealed, though you'd need a restrictor.

[G-Duax]

My '73 has a return line...

 

It runs back to the top of the fuel tank where it dumps back into.

Mine wasn't hooked up when I got the truck, and was a bitch to clean out to get it to flow again.

Had to use multi strand cable (1/8", from McMaster-Carr), and auger it out with a drill, a foot at a time.

Auger a ways in, fill with carb cleaner, let sit, auger some more with progressively longer pieces of cable.

 

Here in Texas, if you don't circulate the fuel, these older carbed engines will vapor lock.

 

I either run a 'T' fitting right before the carb, with the nipple that goes to the return soldered, or brazed shut, and about a .040" hole drilled into it.

That is enough to let vapor pass freely, but small enough to maintain fuel pressure.

 

On my currant DGV, I picked up a second fuel inlet fitting, plugged & drilled it, and use it to return fuel right from the carb.

 

110 degree August heat, stop & go trafic, and Zero vapor locks.