Gas vent hose?
Thread Starter
Instructor
Joined: Aug 2003
Posts: 230
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From: Somewhere in Mo
Gas vent hose?
Filled my 71 up today (fullest the tank has ever been) and started driving and noticed gas smell.... checked underneath and noticed a orange hose out the passenger side of my tank near the top was leaking gas (on my exhaust no less). Temporarily stuck a bolt in the hose to get it home....whats the story on this hose... is it a vent hose or what?
Thanks again,
Timbo
Thanks again,
Timbo
Race Director
Joined: Apr 1999
Posts: 15,134
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From: NM
Originally Posted by Duke94
One hose is from the vapor return line and goes to something called a separator valve then there is another short hose that goes from that gizmo to the tank.
Only thing on the passanger side is the feed and return lines. Feed comes from the bottom of the tank, the return goes to the top of the passanger side of the tank. Is the return line still functioning or has it been cut off?
tom...
Thread Starter
Instructor
Joined: Aug 2003
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From: Somewhere in Mo
The return line has been cutoff just under the passenger door.
This line has a hose clamp about 4 inches from the end, but is just kind of sticking out pointing toward the pass.side inner quarter.
This line has a hose clamp about 4 inches from the end, but is just kind of sticking out pointing toward the pass.side inner quarter.
Race Director
Joined: Apr 1999
Posts: 15,134
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From: NM
Originally Posted by Timbo2
The return line has been cutoff just under the passenger door.
This line has a hose clamp about 4 inches from the end, but is just kind of sticking out pointing toward the pass.side inner quarter.
This line has a hose clamp about 4 inches from the end, but is just kind of sticking out pointing toward the pass.side inner quarter.
tom...
Race Director
Joined: Apr 1999
Posts: 15,134
Likes: 477
From: NM
On unvented systems the vent is the fuel vapor line on the drivers side. If that is in place (fuel line that runs down the frame rail on the drivers side) you should be okay. If you don't have some type of vent you could end up crushing your tank due to vacuum build up in the tank.
tom...
tom...
Safety Car
Joined: Sep 1999
Posts: 4,930
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From: AnyTown NJ
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
On your 71 there is a evaporative emissions control. This consisted of a black plastic canister that was located in the driver's side engine
compartment, roughly in the space between the back of the wheel well and the firewall. The canister had several hoses connected to it.
One hose was connected to the vacuum port on the front of the carb. Another hose was connected to the PCV valve on the left front valve cover.
And another hose was connected to the fuel vapor return line which runs alongside the drivers side frame rail and connects to the vapor separator on the upper left side of the fuel tank.
The fuel return line off the fuel pump is on the passenger side. It's only found on Rochester Quadrajet equipped cars. (there was one Holley carb setup that did use it though). I've read where it's use is to regulate pressure to the carb and also to help prevent vapor lockup.
If someone decided to change the fuel pump on your car to one without a fuel return line, make sure the return line to the tank that was removed is not left open, but is raised up and plugged off securely. The fuel tank can siphon back through the return line...as you've found out.
compartment, roughly in the space between the back of the wheel well and the firewall. The canister had several hoses connected to it.
One hose was connected to the vacuum port on the front of the carb. Another hose was connected to the PCV valve on the left front valve cover.
And another hose was connected to the fuel vapor return line which runs alongside the drivers side frame rail and connects to the vapor separator on the upper left side of the fuel tank.
The fuel return line off the fuel pump is on the passenger side. It's only found on Rochester Quadrajet equipped cars. (there was one Holley carb setup that did use it though). I've read where it's use is to regulate pressure to the carb and also to help prevent vapor lockup.
If someone decided to change the fuel pump on your car to one without a fuel return line, make sure the return line to the tank that was removed is not left open, but is raised up and plugged off securely. The fuel tank can siphon back through the return line...as you've found out.
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Thread Starter
Instructor
Joined: Aug 2003
Posts: 230
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From: Somewhere in Mo
I suspect that's what going on. The return fuel line has been cut just below the driver door and plugged off with a bolt and hose clamp. The line that is leaking is on the top passenger side just kind of sticking out there about a foot. I will look tonight and plug this line securely ( if the vent line on the driver side is in place)
The fuel pump with the return line is still on the car. I suppose I should replace this with one that does not have the return line, therefore eliminating the return line thats capped off all together.??
thanks again guys for your input.
Timbo
The fuel pump with the return line is still on the car. I suppose I should replace this with one that does not have the return line, therefore eliminating the return line thats capped off all together.??
thanks again guys for your input.
Timbo
Pro
Joined: Oct 2003
Posts: 707
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From: Reinholds PA
Just found my leak at rear, it is on top of tank passenger side Return hose was almost off at tank repaced hose put on clamp no leak no more smelly garage It isnt easy with tank in car you must get hand up aside of tank and remove hose ,replace with new one 2 bucks at advance auto parts and use a sring clamp you cant get a screw driver up there to tighten a regular clamp.
Melting Slicks
Joined: Sep 2006
Posts: 2,810
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From: Wichita Kansas
Originally Posted by nutseynut7
Just found my leak at rear, it is on top of tank passenger side Return hose was almost off at tank repaced hose put on clamp no leak no more smelly garage It isnt easy with tank in car you must get hand up aside of tank and remove hose ,replace with new one 2 bucks at advance auto parts and use a sring clamp you cant get a screw driver up there to tighten a regular clamp.
Pro
Joined: Oct 2003
Posts: 707
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From: Reinholds PA
Originally Posted by kansas123
How did you reach up there, clear from bottom, took spare tire off first? I have much gas smell in garage, have only just started chasing it down. Canister lines and canister look okay; there is a rubber hose sticking straight down behind tank nearly to bumper that I suspect is just an overflow. I am thinking that when I didn't have lot's of gas in the tank I wasn't getting so much smell (wishful thinking), that could be a sign of leaking tank, bad news.
I hqad smell for 3 years but it was just that hose
Pro
Joined: Oct 2003
Posts: 707
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From: Reinholds PA
Originally Posted by kansas123
How did you reach up there, clear from bottom, took spare tire off first? I have much gas smell in garage, have only just started chasing it down. Canister lines and canister look okay; there is a rubber hose sticking straight down behind tank nearly to bumper that I suspect is just an overflow. I am thinking that when I didn't have lot's of gas in the tank I wasn't getting so much smell (wishful thinking), that could be a sign of leaking tank, bad news.
hose at top at top of tank I took spare of but think you can get there without doing that it is near muffler
Melting Slicks
Joined: Sep 2006
Posts: 2,810
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From: Wichita Kansas
How about this hose?
If you look in the lower left side at the inset, it says 'Install Flush'; looks like they are referring to that hose, but what does it 'Install Flush' to??? I have felt every fitting on the tank and still cannot find a leak but still have the smell. I did pull the small hose off the vapor canister in the front (pulled it from the front of carb) and tried to blow into it, but no dice. Anyone know what this hose mounts flush to? Thanks!
Le Mans Master
Joined: Jun 2002
Posts: 8,339
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From: I can walk to MA
Originally Posted by kansas123
If you look in the lower left side at the inset, it says 'Install Flush'; looks like they are referring to that hose, but what does it 'Install Flush' to??? I have felt every fitting on the tank and still cannot find a leak but still have the smell. I did pull the small hose off the vapor canister in the front (pulled it from the front of carb) and tried to blow into it, but no dice. Anyone know what this hose mounts flush to? Thanks!
filling area, the gas is trapped in the rubber boot and goes down that hose to fall on the ground. They are saying to install such that the end
of the hose is flush with the end of the vertical portion of the rear bumper.
