Fuel pump to carb line puzzle

Jim,
Thanks for the explanation and detailed parts list. I'm going to order a stage 1 fuel line and some fittings.
What are your thoughts on plugging the fuel return port on the pump? I could run a -6 line back to the tank but also have the plug provided with the pump.

Bob

 

You really only need a -4 or 1/4" return line. The pump you have has a metered return hole that is about 0.030" dia. At 0.030 and 8PSI, at most you are doing about 3 gallons per hour being returned to the tank.

 

Ideally I'd like to plug it and not have a return line since I didn't think to install one when the body was off.

 

You can plug it according to McRobb. If you have some vapor lock issues then you may need to add it later, but certainly isn't mandatory.

 

There's another reason that you MAY need a return line. The RobbMC pump puts out 7 psi + or - 1 psi. Your carb, assuming it's a QJ will probably handle that pressure. However, if the needle/seat won't hold 8 psi, you may need to hook up the return line to the tank.