Map63Vette
Well-Known Member
Years ago when I did my 5.7 Hemi swap in my 67 I got an aluminum tank with an in-tank pump from a place that I don't believe is in business anymore. It's worked out well enough for over 10 years, but I've had a couple of issues with it as well. The main issue I had was the plastic bulkhead "thing" for the fuel pump wiring. I noticed I kept having fuel leak issues after filling up my tank and thought it was a vent line problem, so I capped the vent at the fuel pump flange and just tried to use the standard vent that's built into the fill neck (more on that later). I kept seeing leaks though, so I finally dropped the whole tank to take a closer look and found out the plastic bulkhead for the fuel pump wiring had started melting and left an open hole for fuel to get out of. Not sure how the car hadn't burned to the ground, but glad I finally found the issue. I modified it to use more of a typical isolated stud style bulkhead and the fuel leaks went away.
However, my vent issues have never really been solved from the first day I had the tank in the car. The tank has a pipe stub welded in for the filler neck and came supplied with a short piece of hose to use as a coupler. I cut down a stock filler neck to use with it, which is where I first learned how the original tank actually vented. There is a baffle that runs the full length of the filler neck that separates the top and bottom section of the tube. So in a full factory install, the filler next extends into the tank and the baffle with it. On the new tank, the baffle can't extend into the stub pipe that's already welded to the tank. The stub pipe itself does appear to protrude into the tank some amount, so I believe I should still have expansion area in the tank, but it's caused me no end of grief when it comes to filling up at a gas station. Sometimes it works fine, sometimes it burps a good bubble of gas all over the side of my car and on the ground, etc. I can also never fill it at the full speed auto shutoff click on the pump. I've tried holding the gas nozzle every way I can think, but it's just too random to figure out. I also have a vent line on the fuel pump mounting flange though, which I had originally capped off since the tank vents through the filler neck.. I thought maybe this was also a problem, so I tried opening it back up, but it doesn't seem to have helped anything.
Here are some good old fashion MS Paint pictures to try to explain what I mean better:
I think I'm also having some fuel pump issues, so I decided instead of just replacing the pump, I'm going to replace the whole tank with a Tanks Inc. factory style steel one with the built-in EFI setup. This would get me back to a stock style filler neck, which I'm hoping will let me fill the car normally at full speed with auto shutoff. The fuel pump assembly that goes with the tank has a vent line port on it as well though, so I'm curious what others are doing with it. Are you capping it off and just using the factory venting through the fill neck? Are you capping off the factory vent at the top of the filler neck and just using the one on the fuel pump flange? Or are you running both vents just because they are there?
However, my vent issues have never really been solved from the first day I had the tank in the car. The tank has a pipe stub welded in for the filler neck and came supplied with a short piece of hose to use as a coupler. I cut down a stock filler neck to use with it, which is where I first learned how the original tank actually vented. There is a baffle that runs the full length of the filler neck that separates the top and bottom section of the tube. So in a full factory install, the filler next extends into the tank and the baffle with it. On the new tank, the baffle can't extend into the stub pipe that's already welded to the tank. The stub pipe itself does appear to protrude into the tank some amount, so I believe I should still have expansion area in the tank, but it's caused me no end of grief when it comes to filling up at a gas station. Sometimes it works fine, sometimes it burps a good bubble of gas all over the side of my car and on the ground, etc. I can also never fill it at the full speed auto shutoff click on the pump. I've tried holding the gas nozzle every way I can think, but it's just too random to figure out. I also have a vent line on the fuel pump mounting flange though, which I had originally capped off since the tank vents through the filler neck.. I thought maybe this was also a problem, so I tried opening it back up, but it doesn't seem to have helped anything.
Here are some good old fashion MS Paint pictures to try to explain what I mean better:
I think I'm also having some fuel pump issues, so I decided instead of just replacing the pump, I'm going to replace the whole tank with a Tanks Inc. factory style steel one with the built-in EFI setup. This would get me back to a stock style filler neck, which I'm hoping will let me fill the car normally at full speed with auto shutoff. The fuel pump assembly that goes with the tank has a vent line port on it as well though, so I'm curious what others are doing with it. Are you capping it off and just using the factory venting through the fill neck? Are you capping off the factory vent at the top of the filler neck and just using the one on the fuel pump flange? Or are you running both vents just because they are there?
