Replaced Fuel Sending Unit, now trouble starting
Hello, I have a 1965 Pontiac GTO (with a later year 455). Since the fuel gauge was not working (needle passed Full), I replaced the fuel sending unit. The old one has a 5/16 outlet and the new one that has 3/8 outlet...figured I will eventually upgrade the fuel line to 3/8 as well. The only visual difference between the units (besides the outlet size) is the 5/16 outlet is straight and the 3/8 outlet is angled up a little...maybe 45 degrees. The fuel line is up above the fuel tank so I'm sure sure this is an issue. Before changing the fuel sending unit, the car ran fine...I would pump the gas once or twice and it would fire right up. Now, I have to crank it and pump the gas repeatedly to get it to eventually start. Once it's running it's fine, but a lot harder to start now.
UPDATE: I swapped the old 5/16 sending unit back in and the car starts like it use to. Also, I cleaned the ground wire before install and the fuel gauge appears to be working. So for whatever reason, the bigger 3/8 outlet was causing an issue at start up.
Last edited by aeconfidential; 08-03-2015 at 06:07 PM.