So I finally figured out why I get such bad gas mileage in my 68 307. I'm filling up the other day and I wiggled the filler pipe (the previous owner didn't connect it inside the gas door) and I noticed gas pouring out on the ground. When I looked a little closer it looks like the filler pipe weld is broken where it joins to the tank.

It this something that can be fixed and how? Or should I buy a new tank and where? Also any tips in the R&R are greatly appreciated.

Thanks for any help

...............devin

Hey Devin,

You do know better than welding on that fuel tank, right? Welding on a fuel tank, even when empty = BOOM. You would probably get an explosion that would make an Iraqi Insurgent proud! Then too, there would be the issue of burying the welder. And who would be expected to pay his funeral expenses? The owner of the tank? You?

Gasoline leaks out of the broken weld every time you turn right. The gasoline inside the tank shifts left on right turns and leaks out onto the ground. How much does it shift? If the tank filler neck did not have a cap on it, gasoline would spill out the filler hole on hard right hand turns (with full tank). So, depending on the size of the hole, you could be losing a significant amount of gasoline.

Before replacing the tank, I would try a patch. One type of patching material such as Sonic Weld is too stiff to ooze down into small holes that may exist. If you could find a liquid steel, plastic, aluminum, etc. that will adhere to the existing metal (after a thorough cleaning and sanding of course), that should be worth a try. The thinner the original product is, the better it will be able to ooze into smaller holes and crevices. I believe fibergalss cloth with a good heavy coat of resin would work well, but I do not know if fiberglass is resistant to gasoline.

Maybe some of the other guys on this forum have better ideas.

Hey Devin,

You do know better than welding on that fuel tank, right? Welding on a fuel tank, even when empty = BOOM. You would probably get an explosion that would make an Iraqi Insurgent proud! Then too, there would be the issue of burying the welder. And who would be expected to pay his funeral expenses? The owner of the tank? You?

Gasoline leaks out of the broken weld every time you turn right. The gasoline inside the tank shifts left on right turns and leaks out onto the ground. How much does it shift? If the tank filler neck did not have a cap on it, gasoline would spill out the filler hole on hard right hand turns (with full tank). So, depending on the size of the hole, you could be losing a significant amount of gasoline.

Replacing the tank will cost you at least a couple hundred bucks. So, before replacing the tank, I would attempt to patch the broken weld. What have you to lose? One type of patching material such as Sonic Weld is too stiff to ooze or even push down into small holes that may exist. If you could find a liquid steel, plastic, aluminum, etc. that will adhere to the existing metal (after a thorough cleaning and sanding to bare metal of course), that should be worth a try. The thinner the patching material is, the better it will be able to ooze into the smaller holes and crevices. I would use a small flat tool to press the material deep into the broken weld. A popsicle stick might work well. A small putty knife might be even better. If that does not stop the leak, I would apply a fiberglass patch all around the weld as a last ditch effort at repairing the leak. I believe fibergalss cloth with a good heavy coat of resin would work well, but I do not know if fiberglass is resistant to gasoline so it may not last very long.

Maybe some of the other guys on this forum have better ideas.

JB Weld is holding my tank togther. :)

Check with your local radiator shops. They are usually willing to biol out the tank and solder up any leaks. This does mean removing it from the rig, which can be a dirty job, but at least you can do a good visual inspection and decide if it's worth repairing or just finding one in better condition.

Devin aka 64SS427

Thanks for the radiator shop tip. I think I'll try that first beore I spend the money on a new tank. I'll let you know how it turns out.

.......devin

Id clean it good and use jb weld or seal all it works great on gas tanks.if you use seal all layer toilet tisue on with it to make it stronger.

JB is a poor mans friend.
Cheap, easy to use, gas resistant.
mix equal parts and mix evenly.
apply liberally!!!

I fixed a gas tank once with 60 pin holes in it.
Did not have any problems after JB.

If you do not want to get dirty, then reccomend shop.

When I was younger I had a 68 Goat and was driving too fast on the interstate when it was raining. I hit a wet spot and the car hydroplaned. I hit a mile marker and damaged the door but I also saw gas leaking from the gas tank. I drove to the next truck stop and bought a tube of GE Silicone Sealant, at any rate the leak slowed down and after an hour the leak was 99% stopped. After driving another 80 miles the leak was stopped. I will never forget that night and to this day use a GE Silicone Sealant ( I however have not tried this one on a gasoline leak but you could email GE and ask if their GE Silicone Sealant II in the 2.8 fl oz tube will work on that gas leak. All I can say is back some 25 years ago that product made in 1979 helped me out..

that is too cool, everyone can keep a tube of that in their glove box.
and is easier than JB on the side of the road...