Fuel leak

-
Del

Del

Papa66Bcuda
Joined
Oct 22, 2015
Messages
394
Reaction score
228
Location
Buffalo,Illinois
Does anyone know what causes fuel to run out of vent on tank sending unit . I got this 66 Barracuda with a new tank in it and I pulled it down to do some trunk repair and installed new gasket on sending unit and the new gasket leaked like crazy got that stopped now the fuel runs out of vent tube . I can put tube straight up don't help I put a bolt in it for now and parked it till I can find a fix. Hopefully someone has an answer . Thanks
 
That is a weird one for sure. MOPARMITCH has nos lock rings for the sender if it comes back again. any chance you have a non vented cap and it is building up pressuer due to temp change?
 
Stupid question where does the in tank side of the tube start by the top of the tank or is it just flush with the sender. Might be a return line for fuel if it is flush. Any chance you have a pic of the back of the new sender?
 
The line to carb has an elbow that points up toward trunk and the return side has a 5 1/16 nipple straight out toward front of car . I filled the car up with gas 2 days ago and it had a leak around the o ring and I got that tighten and it stopped but then it started coming thru vent hose at a solid run . I blew air into the vent hose and it stopped for a few seconds then started back up I am confused why when I tighten the lock ring that it made fuel come thru vent hose
 
halifaxhops said:
That is a weird one for sure. MOPARMITCH has nos lock rings for the sender if it comes back again. any chance you have a non vented cap and it is building up pressuer due to temp change?
Click to expand...
I tried with and without cap but no change
 
That should not have made a difference, Those new lock rings are horrible though, if you still have the old one re use it. Is where the vent tube originates in the tank under the fuel level? That is all I can think of or a non vented cap. how was it with the old one? I know stupid question but had to ask.
 
s-l225S9M9C8YX.jpg
Look like this? All I can think of is the inside vent tube is below the fuel level and it is getting pressurized somehow, possibly on a down angle?
 
halifaxhops said:
View attachment 1714947780 Look like this? All I can think of is the inside vent tube is below the fuel level and it is getting pressurized somehow, possibly on a down angle?
Click to expand...
Yes the vent tube is on the bottom directly below the feed line . This is how it was when I took it out but the person before me replaced tank and sender but it only had a couple of gallons of gas in it. Maybe it's not suppose to be that way ?
 
I am wondering if that is for a return line. I would think the vent tube would be going up in the tank. HMMMMM
 
I will take another look tonite I really appreciate everyone's ideas but I have to go to work today for 1/2 day. Thanks again
 
What 66 model had a sender with vent or return port ? To my knowledge not even the C.A.P. builds of 1966 had fuel vapor return.
 
Del said:
Does anyone know what causes fuel to run out of vent on tank sending unit . I got this 66 Barracuda with a new tank in it and I pulled it down to do some trunk repair and installed new gasket on sending unit and the new gasket leaked like crazy got that stopped now the fuel runs out of vent tube . I can put tube straight up don't help I put a bolt in it for now and parked it till I can find a fix. Hopefully someone has an answer . Thanks
Click to expand...


There is no "vent tube" on any factory sender. NONE.

So now, photos might help, or describe exactly what and how you have this plumbed? I mean surely? You don't just have the tube sticking out there disconnected? If you are not using it for a return you must plug it "sealed".

that is easy. Take a short length of hose and a bolt and clamp it "sealed" both ends, just like you would any other fuel line.
 
I was thinking the same thing. The "vent tube" cannot end submerged in gas! I'd cap that extra tube off, then figure out how the tank is supposed to be vented. AFAIK, most '66 Mopars would have the vent in the vented gas cap.
 
The "correct" sending unit should not have a return line. As @67Dart273 said, just take a short length of hose, put a bot in it, clamp the bolt in the hose, and clamp the other end of the hose on the return. Here's a picture of my 66 Barracuda sending unit. I have the factory style ground strap and an added ground running to the frame.

Gas sending Unit.jpg
 
I am guessing that who ever put this new sending unit in put in wrong one . I will plug it. Thanks everyone for your help
 
67Dart273 said:
There is no "vent tube" on any factory sender. NONE.
Click to expand...
The vapor return from charcoal canister ( later models ) was plumbed to somewhere. Anyway... this owners sender is/will be wrong in more ways than one. Gauge needle will go to empty so fast that he'll suspect that capped port has lost its cap. Good luck to him.
 
^^Some 70 models (CA) and later. But they did not go to the sender. These were fittings right in the tank proper.
 
I pulled it out aligned the gasket no leaks and also plugged the vent nipple . I am going to order the correct sending unit and put it in later wanting to take it for a drive this weekend. All you guys are great with helping really is a great site
 
You must log in or register to reply here.
-

Back
Top