Tank vent line is puking fuel

[Hilljack68]

In the six years I've had the Coronet (68), I've always smelled gas when I come home from a ride. I found out why yesterday... the vent tube will puke fuel when I come to a stop. She has an aftermarket tank, and I'm not sure the fuel vent was run properly. The one vent tube goes up into the trunk of course, but the other runs up to the trunk pan and just hooks back down - right behind the shock mount (you can see where the mount is soaked).

Where should this line actually go? I checked the shop manual, but it wasn't really clear.

 

[Hilljack68]

Could the lines be installed in the wrong ports? I just read a post from Wayne that repro tanks might have the ports reversed.

 

[70 sublime]

On a Charger because it has the filler cap on the quarter panel the little vent line runs back down the filler neck and vents into the frame rail
Is there any factory holes in the frame rail that are close by that that might work ?

 

[moparsaver]

Is this hose damaged?

 

[Hilljack68]

Is this hose damaged?

Yeah, I spotted that this morning. I knew some one would see that - LOL. I just replaced the hose on the actual fuel line, and then saw that one. It's not leaking though. But have you guys experienced what Wayne was talking about? And where is that line supposed to go...back to the filler neck, or right where it is?

 

[davek]

On a Charger because it has the filler cap on the quarter panel the little vent line runs back down the filler neck and vents into the frame rail
Is there any factory holes in the frame rail that are close by that that might work ?

charger is a different setup

 

[davek]

coronet vent ends up over the pass side shock tower,revers lines to see if vent lines are backwards.

 

[Kimodc]

I have the same tank and vent line set up on my 69 sport satellite. I have an aftermarket tank and factory vent lines that are all in good shape and hooked up correctly. My car will puke a little fuel from the vent line each time after I stop. When I stop the car and turn it off, it takes about two minutes for pressure to build and then it spurts a little gas out the vent line. I stop this by waiting the two minutes, then opening the filler cap and releasing the pressure. I can’t figure out why it does this, but it seems like it’s a common problem, even with everything correctly installed.

 

[dadsbee]

Long line to short line! Meaning the short shock tower line should be hooked to the long line in the tank that goes right back to the filler neck area. The long line up into the trunk should hook to the short line in the tank.

 

[Hilljack68]

Both lines coming out of the tank are the same length. Also, there is no line going toward the fill neck. Mine is like Dave's picture shows.

 

[dadsbee]

Go find my restoration thread that shows actually pictures of of inside a tank. I'm not talking about the length the tube sticks out of the tank. On one of them the tube is ran inside the tank right back to the filler area.

 

[kiwigtx]

It will all make sense when you look at the two different tubes inside the trunk, and realise that there is a short tube and a long tube inside the tank.

These different lengths allow for parking on an incline - either facing down or up a hill.

Also make sure that you didn't over-tighten those Jubilee clips (screw clamps, or whatever you non-Metric people call them)

 

[sc440]

Is this what is going on?

 

[kiwigtx]

Is this what is going on?

View attachment 1471466

Exactly. And if the fuel is high enough (full enough tank) then it slosh around and give a similar effect in your garage.

I had a similar issue many years ago when one of the small vent outlets had been blocked. Easy enough to clean out when you know what the problem is.

 

[Hilljack68]

Ok, I get it. Thanks for the info. But seeing as those tubes are inside the tank, how can I tell which one is the long and which is the short?

Oh, and did the rear-fill tanks have a vented or non-vented cap??

 

[sc440]

Don’t think my 69 has a vented cap, really only way I can think to check them would be get a thin piece of wire(maybe some mig wire) bend a small hook on end stick in vent and try to find end of tube in tank.

 

[moparedtn]

Ok, I get it. Thanks for the info. But seeing as those tubes are inside the tank, how can I tell which one is the long and which is the short?

Oh, and did the rear-fill tanks have a vented or non-vented cap??

All this great help sort of forgets that nobody here (at least as far as is known) can see through steel....
It would be more helpful methinks to say "drivers' side nipple" and "passenger side nipple" or some such??

 

[dadsbee]

View attachment 1471783
All this great help sort of forgets that nobody here (at least as far as is known) can see through steel....
It would be more helpful methinks to say "drivers' side nipple" and "passenger side nipple" or some such??

Yah.. but it doesn't work that way because repro tanks, as numerously noted, get done backwards. Remove the cap with the tank low on fuel... grab a flashlight and check. If that fails grab an inspection camera to have a look. If that fails fill the tank FULL.. get a bucket and pull both rubber joiners off the tank. Which ever one stops flowing fuel first is the long line.

 

[Hilljack68]

Don’t think my 69 has a vented cap, really only way I can think to check them would be get a thin piece of wire(maybe some mig wire) bend a small hook on end stick in vent and try to find end of tube in tank.

Great minds think alike! I just saw your response after doing that very thing. I used a piece of solid romex wire, bent up on the end, and pushed til I got no resistance. The verdict?... the tubes are placed correctly. Now I'm wondering about the vented vs. non-vented caps.

 

[steve340]

The standard 1968 cap is non-vented. However I saw an article in Mopar Action that said you can swap to the later style vented type.
I did this it works fine, purchased a new one off EBAY. This might solve some of your problem.
My car used to stink and even drop liquid fuel out of the chassis rail after I replaced the fuel tank damaged during shipping to New Zealand.
I believe something must not be quite right with those repop fuel tanks.
I modified the tank vents and fitted the new cap and good as gold now even on a really hot day.