The gas tank is leaking on my 69 Road Runner

[eastyorker]

Yes, when I fill it right up it leaks from the top of the tank. Looked at the seam on the side and it's okay. Not leaking from the sending unit as well. The sending unit also doesn't work. So I never know how much is in it.

Any ideas? What else can I look for? I'm about to drop the tank and look, just want to get prepared. What can be done with the sending unit?

Thanks

Darryl

 

[bigmanjbmopar]

O ring at filler neck needs to be replaced, as far as the sending unit have you tested the gauge? Take the wire off your sending unit and make a wire jumper and use it to touch the sending wire to a good ground, key on check the gauge to see if it goes all the way to full, if it does not move you have an issue in your gauge cluster. If it does move replace your sending unit when tank is near empty.

 

[eastyorker]

Already replaced the O ring. Still leaks. Is there anything on top of the gas tank? A vent or anything that gas will leak out from? Seems to pour right off the top of the tank.

Thanks for the info about the sending unit. I'll check that out tomorrow.

 

[bigmanjbmopar]

Yes, two vent lines one through trunk with a u shaped bend in it. goes through body plug into tank via outlets near sending unit the other from tank to top of body near rear end and just turns down, that one is the one you usually smell gas from on hot days with a full tank. anyway the only way the one through the trunk could leak is if it had a hole in it or was split some how.

 

[ChargerRTguy]

A suggestion would be to check the alignment of the filler neck and the tank. I had a similar problem, when I filled my tank, gas would pour down the tank. At first I put a new grommet in, and that did not stop it. What happened was the tank was out of alignment with the filler tube and the mis-alignment caused to leak around the seal.

 

[no462of12K]

if u cant find the leak put less gas in tank leak goes away

 

[Meep-Meep]

I suspect the sending unit gasket but you seemed to rule that out. Is / was your car rusted? What about a rust hole in the top of the tank? The vents are in the corners if I recall and nothing near the center top of the tank to leak.

 

[69redrunner]

There are two rubber hoses that are between the vent nipples on the tank and the vent tubes themselves. I had an issue with fuel leaking and found one of the hoses was kinked. Replaced the hoses and cured the leak.

 

[eastyorker]

Turns out there is a pinhole on the top of the tank just near the drivers side. Now the search got a new one starts.

After grounding the sending unit it still doesn't work. What do I need to look at with the dash?