Gas tank tubes

[slo929]

Hi all..

I have a dilemma... I dropped the gas tank on my '72 and at this point i have the tank down to bare metal but I have found 2 problems. Problem # 1 is that the fuel supply line (coming out next to the tank transmitter unit) is clogged. Any ideas on how to unclog the line without boiling the tank? Problem # 2 is both the fuel supply line pipe and the fuel return line on the tank are loose. Is JB weld a good fix? in dogmas post that helps eliminate the expansion tank he uses JB weld for the caps he uses. will jb weld hold up or how should i fix the two pipes?

Thanks for any and all info.

[Nissanman]

You could try inserting some small diameter stiff wire through the pipe.

That should dislodge anything trapped inside the tube.

A dose of carburetor cleaner and a squirt of compressed air would help too.

Trouble is, the blockage, may very well end up inside the tank, ready for a re-run.

As for the loose pipes, sounds like they need to be re-soldered.

Use an electric soldering iron which will have no naked flame.

Build the solder up in a mound where the pipe exits the tank to improve the mechanical strength.

I personally don't like the idea of using JB Weld for that, just my opinion.

After you have finished the repairs, give the tank a good rock and roll with a small amount of solvent or de-greaser to wash out any sludge.

[ph240]

JB weld may work. Gas will not effect it., but I agree with Nissanman. The factory soldered the connections. The pipes are soldered to a plate that is spot welded and soldered sealed to the tank. I would not heat the whole plate as you will unseal the plate to the tank. I think you would be better to solder the the tubes back. Either way you should pressure test the tank with about 5 psi and check for leaks. You may have to have a local shop do this. Do not apply more air pressure as you can hurt the tank.

Welding wire or a coat hanger should dislodge any rust/debris. I would turn the tank up side down and have the drivers side (shallow end) up higher so when the debris comes out it will fall into the tall part of the tank; on the other side of the baffle, were you can vacuum it out thru the sending unit opening or the filler neck. You may need to soak it with WD40 for a while.

[Marty Rogan]

As long as you already have the tank out, I would take it to a good radiator shop. They can boil it out, weld/solder the joints and re-line the tank. They don't charge that much for this service.

Once you have this done, you shoulnd't have any more gas tank issues.

Marty

[JimmyZ]

I used JB weld as a temporary fix for one of my vent tubes. You have to sand and make the metal perfectly clean or the JB won't stick. Remember this is temporary.

You will be much better off having a radiator shop boil and solder the tank.

Gas is something to be taken with deadly seriousness. You've no idea what kind of fire/possible explosion you'll be looking at if your tank catches fire. Death is fairly certain and actually to be hoped for if the tank goes up. No kidding.

I wouldn't screw with it and I have sweated copper, done TIG, MIG,Stick and Oxyfuel welding/brazing. Someone who does this day in and out is the person you want to do it. They will have the right lead alloy, flux, etc.

Here's my gas tank page if you're interested...

http://warbuddies.homestead.com/gastank.html

Jim

[JimmyZ]

Gas is something to be taken with deadly seriousness. Jim

Meant to type "dead seriousness" as a screwy pun.

BTW laquer thinner is one of the BEST solvents for removing varnish from your tank. It will help get the lines squeaky clean too. Pour in half a gallon and let it set for a few hours to a few days in various positions.

If you have any rust (I suspect you will) then Hirsh's tank etch is great. Once again, you have to let things set to work. Definitely use the laquer thinner first.

All of this is assuming that you don't want to spend the $100-$200 for the radiator shop to tackle this... That you're going to do the JB weld route.

[slo929]

Thanks for all teh info... I suppose I will look into having a shop boil it out for me tomorrow. Thanks again for all the input!

[slo929]

well I got the tank back from the radiator shop with the new fuel supply line installed correctly (the original clogged one had holes in it after the tank was cleaned out) so thanks for the input once again.

Another question though. I have a nice 2 inch piece of galvanized tubing that I could use to replace the plastic piece in the filler neck. It is the exact size as the original plastic 3/8 tube but will the galvanized metal last (or have some strange reaction to gas?) in that spot? Most people used copper and I have a bunch of 1 inch pieces of copper, but they just seem too short. any input would be great.