The mechanical fuel pump has a fitting on the back to allow excess flow to be vented out. Van's supplies a brass and copper fitting that connects here and is then run through some nylon tubing to a metal tube that vents out, under the fuselage of the airplane. Over all it came out very nice.
Fuel Pump Overflow Line Installation
Metal Tube Bent To Vent Under Fuselage
Brass/Copper Fitting Connects To Mechnical Fuel Pump
