I have a 69 cutlass with a two line fuel pump. Bought a new pump today from carquest and it has three lines. Can I use it? what is the difference??

 

Just a shot in the dark, but fist thought would be for the charcoal canister, or possibly a vacuum pump. I remember reading about older 50's vintage cars having a vacuum pump either built into, or just off the fuel pump to assist the wiper motor in low vacuum situations. I am thinking either way that pump is wrong application. I would call the parts store and get the situation resolved before trying to install that pup.

 

Actually, the third line is fuel return, used mainly on A/C and high perf cars. The fuel return recirculates some fuel to the tank to help avoid percolation in hot engine compartments. You can safely cap the third line and use the pump.

 

Thx. for the education Joe. I figured I was going to be off on that one, but could not come up with a better answer