I removed my gas tank to perfrom the major welding job thats needed for the trunk area. Upon furter inspection of the gas tank, I noticed that the filler neck is leaking very bad at the seam. Now I know why I only got like 6-7 mile per gallon! I also have a hole on the top right (passenger side) of the tank. I took the tank to a repair shop and they fixed the leak. They did not know weather my tank was vented or not so I asked them to fill in the hole anyways. My question is this, is my gas tank suppose to be vented?? It literally states on the gas cap that this is a novented cap and to open slowly to avoid fuel spray. Oh, my car is a 1964 Cutlass.

 

Your tank is supposed to be vented. The non-vented cap indicates the nipple at the top right was the tank vent. There should have been a tube running over to the gas filler neck recess in the body.

If you filled it in you will have to get a vented gas cap, otherwise your car will literally run out of fuel, assuming the fuel pump doesn't implode the tank trying to suck fuel out of it. Any enclosed vessel needs a vent to atmosphere to allow air to replace whatever's being pulled out of the vessel.

 

Ok, I understand. So I need to run a vent hose from the hole that I had covered?? I asked the repair shop to put a nipple there so I can install a rubber hose just incase I need a vent. Is this vent hose part of the fuel line that run inside of the trunk?? There is like a "U" shape metal line that is located on the passenger side inside the trunk that is attached to the rear wheel well (see Picture below) Is this where I am suppose to install the vent line??

101_2680_zpse36fbb93.jpg

 

Yes that is the tank vent on that year and model. You should see two exposed ends on the underside at this point. One end would be attached to that nipple on the tank by a rubber hose.

Rockraider is describing the later models that vented near the fuel filler neck.

 

Actually I was going by the 64 big car vent routing. I keep forgetting the Cutlass was an all-new design that year and the filler neck was behind the license plate.

 

Should someone working on or around a gas tank be smoking a pipe?

 

That would depend on where he put it when he took it out.

- Eric

 

LOL! We removed the tank before we started working on the car.

 

Thaks for the info! Now I finally know what that line is for thats mounted to the rear wheel well!!!! Im glad I didnt rip it out! LOL!!

 

Just a heads up - if you don't want to keep messing around with the old tank you can get a new one on Rock Auto pretty afford-ably & they are made in Canada, not China. I just did one on my car & I was happy with it.