Jump to content

Gas tank leak on angle


Recommended Posts

I was bleeding my brakes on my 48 Windsor. I had the right rear jacked up. The car was at an appreciable angle.  While crawling underneath to  connect to the left rear (not jacked), I noticed gas dripping from what seemed to be an upper seam of the gas tank! It was on or above an edge seam just below where the filler neck joins the tank. I couldn't see it properly "leaking", but seems to be directly due to the angle the car was jacked up.

 

Before going into rip and replace, is there some kind of venting opening on the gas tanks that would cause gas to come out if you angled the tank appropriately? I don't get any drips otherwise, and the gas cap releases pressure when I fill up. No gas smell in the car.

 

Thoughts?

Edited by wagoneer
Link to post
Share on other sites

If the tank were pretty full I'd suspect it coming down from the sending unit or gasket.  I don't know if the 48 windsor has the rubber access plug in the trunk under the carpet but if so it's an easy check.

Link to post
Share on other sites

The vent on our cars is built into the gas cap.  As far as I recall the only opening that are designed into the tank is the sending unit hole, the fuel pickup connection and the filler tube opening.  Two of them use some sort of gasket to seal and they could be old and deteriorated, the fuel pickup uses no gasket and isn't located where you say the leak is.

 

Or you have a hole in your tank that isn't supposed to be there, only a close inspection and maybe a pull and air test can say for sure.

Link to post
Share on other sites

The aftermarket sender in my new tank leaked fuel around the terminals which were loose. I also sealed the pulled rivets holding the sender together. No leaks since.

Link to post
Share on other sites
14 minutes ago, Jerry Roberts said:

Isn't your gas cap supposed to be vented ?

All the modern replacement caps I've seen are pressure relief type and almost always have too stiff of a spring.

Link to post
Share on other sites

The tank on my '48 P15 is unvented and relies on the cap for venting.....I thought all Mopars of this vintage were the same.

 

If unable to find a vented cap you can drill a very small hole in the filler neck under the cap. Here is one I drilled when I was initially troubleshooting fuel delivery problems, it makes a good backup in case the tiny vents in the cap plug up:

 

fuel-cap-3.jpg.46f54a1126a354cb00c91f6196e55dd8.jpg

Link to post
Share on other sites
1 hour ago, 50mech said:

All the modern replacement caps I've seen are pressure relief type and almost always have too stiff of a spring.

 

 

Exactly right, I had this issue with my 51 when I bought it.  First time I opened the cap it spewed gasoline out.  So I bought a new cap thinking the old one was defective.  New cap did the same thing so I ended up taking it apart and cutting the pressure relief spring down, no more spewage and I no longer hear the gas tank "oil can" as it heats up.  Center one in the pic.

 

 

valve apart.jpg

Edited by Sniper
Link to post
Share on other sites

The tank in my 48 Dodge had a crack in the tank at the top left corner, just behind the filler tube.  It would only leak if the tank was full.  I ran the car for a year or so by filling the tank half way.  Finally I took the tank to a radiator shop. He cleaned it, soldered the corner, and fixed the cracked filler tube.  That was 10 yrs ago and all has been fine since. 

 

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use