Fuel Tank ????'s

[5150]

I got my used gas tank out today and took the air drill out getting all of the crap off of it before I hit it with the black chassis paint. I was just wondering what are the other three outlets coming out of the gas tank for??? Obviously the big one is for fuel to enter, but was just wondering what all the other crap was for.

I know it's a stupid question that I should know, but I don't so help please

[Burt4x4]

Vents that connect to a tube on the driver's side neer the fender well inside the bed, should be a metal tube standing vertical..don't have a pic handy, maybe someone else does.

[herb101]

Originally Posted by Burt4x4

Vents that connect to a tube on the driver's side neer the fender well inside the bed, should be a metal tube standing vertical..don't have a pic handy, maybe someone else does.

The large is obviously the filler, the medium is the filler vent, the two at the top front corners are vents and the one on the sender is the fuel supply.

Herb

BTW - my toes are toward the front, so the back is at the top of the shot.

[5150]

So, do I even need these other lines??? Obviously need the fuel line but do I need the other three. If so, where to they go? I have a 88-98 fuel door and tube.

[herb101]

http://67-72chevytrucks.com/vboard/s...=212828&page=2

Post 31 shows the medium size hose and its route to the filler neck. The other two connect to metal lines that run parallel with the bumper on the driver's side rear. My lines are rusted through there, so I don't yet know where they finally wind up. I would guess a charcoal canister somewhere.

You'll need some kind of vent to be able to fill the tank, as the air has to escape to let the fuel in.

Herb

[DURRTY]

you need to vent the tank to keep from building pressure. The only one you need to run to the front is the fuel line to the pump. the other 2 for emissions testing i guess
don't know the official reason they are there but i know you don't need them to run up the frame to make the truck work.

so no and yes you don't really need it but you do need to vent it. I would the vent up near the filler hole and vent it there. just to keep it out of harms way.

[5150]

Thanks for the link. So in essence I just cap the two lines that I've circled from your pic, correct???

[meathead95]

if you cap those 2 lines it will fill slower

[bdas70chevy]

can u use one of the two for a return line for fuel injection? if need b?

[5150]

So, just leave them alone without hoses????

[red71cheyenne]

The tank on my 69 doesn't have anything hooked to those. Just a little length of hose on the left side for venting purposes. So yes, you can leave them alone and it should be fine. On my 71, I ran the return into the left side for the fuel injection and capped all the others off. It does fill a little slow, but still works fine.

[jfortner]

Both of those on my tank go to a small round cylandar next to the fuel filler; behind a square box cover. Then there is also a third line from that cylandar runs all the way to the front of the truck; but isn't connected to anything?

Just an option?

[red71cheyenne]

It went to the charcoal canister for emissions. My 69 doesn't even have it and I removed it from the 71. If you don't have emissions testing where you live, don't worry about it.