Fuel Lines go to roof? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Piper71c10 · 09-17-2003, 08:41 PM

These lines were connected to my stock gas tank when I pulled it. They look as if they go up into the cab and terminate near the roof somewhere. How do I get rid of them? they won't just pull out after I removed the bolt holding them in place.

**Ironhorse** · 09-17-2003, 09:25 PM

Piper, Brace your self and give a good firm pull on the two lines. They are actually one line that loops back into itself. I did the same thing on my 71 4x4 when I moved the in-cab tank to under the bed. The lines are old and stiff and fit rather tightly into the door pillar cavity. It looks as if your seat and tank are both out so you should be able to reach up into the pillar and feel for any attaching hardward but on my truck there was none. Get a good hold and PULL !

jef5150 · 09-17-2003, 09:37 PM

i think theres 1 bolt you have to take out ,it holds the clip ,,,,,,,,,jeff

Bowed · 09-17-2003, 11:39 PM

I was told on a recent post those lines are an emissions loop . what will happen ( if anything ) to the emissions testing of the truck if they are bypassed ?

lukecp · 09-17-2003, 11:42 PM

I THINK they let fuel vapors condense back into liquid and run back into your tank. I dont think they really hurt much besides saving you a little bit of gas....

Fleetlover · 09-18-2003, 08:31 AM

One line goes out under the floor along with the fuel line and attaches to a charcoal canister in the engine compartment Another line goes from the canister to the intake to burn off the vapors. A rudimentary emissions control Mine is not hooked and truck went thru inspection . If it ws missing I doubt many shop techs would even know .
George

*Gee_Emm* · 09-18-2003, 09:15 AM

Those lines are unique to 71 and 72's

tom hand · 09-18-2003, 10:20 AM

The only purpose of those was to keep raw gas from being sucked into the charcoal canister...you might want it if you are still using that. Ethier one missing will not effect emissions testing UNLESS you live in a state that does under hood inspection.

Longhorn Man · 09-19-2003, 11:43 PM

The emissions that this helps to prevent is vapor emissions. The same reason most every gass station has those big goofy looking rubber deal on the pump handles.
The vapor canister actually gives you a tad better MPG and a bit more off the line torque.

09-17-2003, 08:41 PM	#1
Piper71c10 Unending Project Join Date: Aug 2003 Location: Sequim, WA Posts: 337	Fuel Lines go to roof? These lines were connected to my stock gas tank when I pulled it. They look as if they go up into the cab and terminate near the roof somewhere. How do I get rid of them? they won't just pull out after I removed the bolt holding them in place. Attached Images

09-17-2003, 09:25 PM	#2
Ironhorse Senior Member Join Date: Jul 2001 Location: Wellington, Ks Posts: 10,294	Piper, Brace your self and give a good firm pull on the two lines. They are actually one line that loops back into itself. I did the same thing on my 71 4x4 when I moved the in-cab tank to under the bed. The lines are old and stiff and fit rather tightly into the door pillar cavity. It looks as if your seat and tank are both out so you should be able to reach up into the pillar and feel for any attaching hardward but on my truck there was none. Get a good hold and PULL ! __________________ 1971 Chevy 1/2T 4x4 LWB 350 V-8 Was sm465-now 350TH/np205 Tilt, Tach, Towhooks Original Truck AM/FM Wellington, Ks

09-17-2003, 09:37 PM	#3
jef5150 Inline 69 Join Date: Apr 2003 Location: valleysprings,california Posts: 1,018	pic i think theres 1 bolt you have to take out ,it holds the clip ,,,,,,,,,jeff Attached Images

09-17-2003, 11:42 PM	#5
lukecp Formerly yellow72custom Join Date: May 2001 Location: Austin, TX Posts: 7,531	I THINK they let fuel vapors condense back into liquid and run back into your tank. I dont think they really hurt much besides saving you a little bit of gas.... __________________ '72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg

09-18-2003, 08:31 AM	#6
Fleetlover Registered User Join Date: Aug 2003 Location: Along the Erie canal NY Posts: 124	cab lines One line goes out under the floor along with the fuel line and attaches to a charcoal canister in the engine compartment Another line goes from the canister to the intake to burn off the vapors. A rudimentary emissions control Mine is not hooked and truck went thru inspection . If it ws missing I doubt many shop techs would even know . George __________________ 71 C10 Short Fleet coughing and sputtering down the backroads 59 Apache short fleet resto started now suspended 1884 victorian home Current restoration project 1997 GMC Sierra Z71 1973 Harley FLH undressed 1949 male body somewhat abused but still starts most mornings

09-17-2003, 11:39 PM	#4
Bowed Registered User Join Date: Oct 2002 Location: where it's hot Posts: 1,059	I was told on a recent post those lines are an emissions loop . what will happen ( if anything ) to the emissions testing of the truck if they are bypassed ?

09-18-2003, 09:15 AM	#7
Gee_Emm Account Suspended Join Date: Sep 2000 Posts: 3,991	Those lines are unique to 71 and 72's

09-18-2003, 10:20 AM	#8
tom hand CCRider Join Date: Feb 2000 Location: Olive Branch,MS,USA Posts: 2,232	The only purpose of those was to keep raw gas from being sucked into the charcoal canister...you might want it if you are still using that. Ethier one missing will not effect emissions testing UNLESS you live in a state that does under hood inspection. __________________ 72 GMC Sierra SWB almost finished---- 84 Softail Olive Branch MS

09-19-2003, 11:43 PM	#9
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	The emissions that this helps to prevent is vapor emissions. The same reason most every gass station has those big goofy looking rubber deal on the pump handles. The vapor canister actually gives you a tad better MPG and a bit more off the line torque.



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