Return line

[pauls63409]

What is the purpose of fuel return line and how does it work?

 

[mpris]

One of the purposes of the fuel return line is to keep the fuel circulating through the lines. This help prevent vapor lock by keeping the fuel cooler.

Poocho

 

[59elcooldsuv]

Another possible purpose is to use a high pressure fuel pump to be sure you get enough fuel delivery at high rpm without flooding it during idle.

The higher pressure will by-pass the float valve in the carb. A fuel pressure regulator will let the gas flow when it's needed but route it to the return line while idling or cruising.