I just bought a dual action fuel pump since I have vacuum wipers and they tend to stall when you need them most, like passing. No instructions were included. Do I install the second half of the pump in series with the line to the manifold connection or simply vent the output side of the fuel pump to outside air? Truck is all original so want to keep the wiper motor Thanks
The 55-59 Chevrolet Truck Factory Assembly Manual shows RPO (Regular Production Option) 340, "Fuel and Vacuum Pump Instruction" only for 6 cylinder engines. The drawing shows the vacuum line from the intake manifold below the carb running to the port on the pump furthest from the oil pan. Then the port on the pump nearest the oil pan goes to the wiper motor. Both lines are metal, steel if I remember correctly. The connections to the pump are made with short pieces of rubber tubing. The page shows RPO 340 as available for truck models 4502, 6702 and 6802, so it may not be correct (although highly desirable) for small trucks.
