I picked up some new 11.11mm Walbro carbs and the hookups are different than the old one.
Please tell me if I am correct here....

One of the lines supplies fuel to the carb and the other returns fuel to the tank.... correct?

I can blow in one and not the other. Is the one I can blow in the supply?

Why does it need a return line?


Edit, the new carbs do not have a primer bulb

You can't blow in the supply, the inlet needle takes more pressure than you can proved to move it off its seat....
Doesn't need a return line to the tank..Some chainsaws and garden equipment use the return...If there's a small tube in the side of the carb you can blow in, plug it. It was connected to a one way valve on the equipment the carb was made for..The carb won't work right with an air leak in the side..

Ok, thanks
Man the drawings/exploded view on the Walbro site are really hard to read!
This is a wt-391
I will just have to try it when the weather breaks.