Weeping Gas tank...

[Nerobro]

I tell you, my gas tanks have issues.

The current problem.

Two weeks ago I noticed the paint on the bottom edge of my tank peeled off. I assumed it was because I had an overflow at some point, or my petcock was being a pain in the bottom.

So I replaced the petcock gasket. any leakines I had went away. my petcock was dry for days.

so cleaning the tank again. more paint came off on the rag. More fuel in my paint. I can't figure out why......

Long story short. somewhere along the seam on the bottom of my tank, it's leaking. This drips onto the petcock lever, and then onto the ground. Missing both my pod air filter, my shift lever, and peg. At first I thought it was a magic puddle ;-) now I know what it is.

SO.... if I can find this problem leak. how do you reccomend sealing it?

Radiator shop? POR?

My first instinct was to drain the tank, fill it with something less nasty than gasoline, pressurize it a bit, and REALLY find the leak. Using htat information, set up the tank so I can pool epoxy on it, and lay a puddle of 12 hour epoxy over the hole. sealing it permanantly, from the inside of the tank. maybe even adding some pressure so the epoxy would flow into the hole.

So... leaky tank fix ideas.. I need them.

[retrex]

Re: Weeping Gas tank...

I tell you, my gas tanks have issues.
So... leaky tank fix ideas.. I need them.

Before I would do anything I would do a complete drain, cleaning and disassemble. I would then use a light and dental mirrors, or broken mirrors on a stick to scope out the interior for rust. Look for really bad areas and press on from the out to test structural integrity. Even though it may be leaking at a seam you really can't know what to do until you do a thourough inspection. If it is just the seam and I wasn't going to do a complete repaint of the tank at this time I would use the POR store tank sealing kit. I have their US Tank sealer in a 20+ year old tank and it still looks good. Good Luck

[argonsagas]

Take Retrex's suggestion.....do a thorough check.

Hopfefully it will be limited to a gasket at the petcock. If not, try these:

You can pour a sealant into the tank, and that may work, but it would depend could prove only temporary if the metal long the bottom of your tank is poor/rusted.

Metal does not corrode only in a single spot, so, if there is one small leak, it is almost certain that more weak areas are nearby, and progressively getting weaker. Pressurizing the tank will blow out the weakest, but will not necesarily show you the entire extent of the rusted areas


If you do find leaks, repairs depand on wallet size. Professional repair is recommended.

That said, if the wallet is pinched, and you can handle the body work, you can sand the lower half of the tank and lay on fibreglass cloth, (NOT the loose fibre-type, but woven cloth) in two separate layers. You must make sure the fibreglass covers the ENTIRE lower half, and you must have no loose, bubbled, areas.

Once it is done, you must coat the inside of the tank. Do this before painting, as even small spills may damage paint.

Sand and prepare the tank for paint, then follow the instructions located at "In the Garage" and ride on leak-free.

[rek]

ok, this is what i did and it worked for me and hpoefully it will work for you. my tank had lots of leaks at the seamS from rust. i first got some Great Stuff, rust convertor in a bottle not a spray can. i then treated the tank with the deruster. after i removed the float and the petcock. be sure to have it outside as the fumes are noxious and don't have it on anything of value as the deruster that leaks out may harm it. i then rinsed with water and put in the sun for a couple of days to get out all the moisture.after i covered the petcock hole w/tape i then took a can of fiberglass resin and mixed about 6oz at a time and began to pour it into the tank fill as i positioned it to flow in the worst areas first. over the next couple of days i put about half a 32oz can in and let it cure out overnight from the last application. then removed the tape and drilled out the hole that was now covered. i reassembled the tank and it has not leaked since!

[DaveDanger]

The kits from POR-15 look to me to be a great way to go. They'll seal up pinholes without any additional reinforcement, but can be ordered with a fibre mat/cloth to assist with reinforcement if its needed. I do agree that you can't spend too much time cleaning the tank interior. I actually am in the process of doing mine as we speak. Rusted pretty badly internally, and had been re-sealed (very poorly) once before, so I ordered the POR-15 kit that includes a stripper for old sealant. Hope to have mine on the bike by the end of the week.

[Joe Nardy]

Re: Weeping Gas tank...

I tell you, my gas tanks have issues.

The current problem.

Two weeks ago I noticed the paint on the bottom edge of my tank peeled off. I assumed it was because I had an overflow at some point, or my petcock was being a pain in the bottom.

So I replaced the petcock gasket. any leakines I had went away. my petcock was dry for days.

so cleaning the tank again. more paint came off on the rag. More fuel in my paint. I can't figure out why......

Long story short. somewhere along the seam on the bottom of my tank, it's leaking. This drips onto the petcock lever, and then onto the ground. Missing both my pod air filter, my shift lever, and peg. At first I thought it was a magic puddle ;-) now I know what it is.

SO.... if I can find this problem leak. how do you reccomend sealing it?

Radiator shop? POR?

My first instinct was to drain the tank, fill it with something less nasty than gasoline, pressurize it a bit, and REALLY find the leak. Using htat information, set up the tank so I can pool epoxy on it, and lay a puddle of 12 hour epoxy over the hole. sealing it permanantly, from the inside of the tank. maybe even adding some pressure so the epoxy would flow into the hole.

So... leaky tank fix ideas.. I need them.

With all the bikes you guys have in that Aurora salvage yard you can't come up with a better tank?

Joe

[Nerobro]

Sure.... But it's severely dented. :-) My orininal tank is quite well sealed.

Hmmm... dent removal?

[Joe Nardy]

Sure.... But it's severely dented. :-) My orininal tank is quite well sealed.

Hmmm... dent removal?

I've never done it but I've heard you can pop some dents out by pressurizing the tank............but you can blow the seams out too.

Joe

[BigMattyD]

I've heard that the best way to pop dents out of the gas tank is to pour out the old fuel, then put about 1 cup of fuel back in the tank. Take the tank out to your backyard, and drop a lit match into the filler hole.

The pressure released by the expanding wall of flame permanently removes dents. It may also remove your flesh.

[dcaswell]

I am surprised that pouring fiberglass resin in works. I am assuming it is polyester resin. That stuff shrinks forever and eventually it does not seal. I just use epoxy resin on our 33 year old boat now if it is just patching holes without cloth, eventually polyester resin is guaranteed to pull away, epoxy just works. Sealing a metal tank with polyester resin is certainly something to watch closely

[retrex]

Worked for me

The kits from POR-15 look to me to be a great way to go... so I ordered the POR-15 kit that includes a stripper for old sealant. Hope to have mine on the bike by the end of the week.

I tried the POR stripper on a Kreem lined tank and it worked only so so. What works great is Chem Dip carb cleaner and SS nuts and bolts. Sealed the openings and swished it around and then let it sit. Reapeat and rotate resting position over a 24 hr period. Got 99.99 percent of the old sealer out. I couldn't even scrape off the remaining .001 percent. Remove nuts and bolt with a magnetic probe. Their US tank sealer works great. Follow the process to the letter. Good luck.

[GregM.]

Has anyone ever used small ball-bearings for this, in stead of S.S. nuts and bolts?? Would they still help get stuff of the inside of the tank? Yet they would't be quite as harsh.

And what are some good ideas on how to temp. seal-up the fuel gauge float opening and the petcock opening??

I think, I need to do this too.

[retrex]

Tank cleaning tips

Has anyone ever used small ball-bearings for this, in stead of S.S. nuts and bolts?? Would they still help get stuff of the inside of the tank? Yet they would't be quite as harsh.

And what are some good ideas on how to temp. seal-up the fuel gauge float opening and the petcock opening??

I think, I need to do this too.

You want sharp edges to cut into the surface of the old sealer, it is not going to hurt the inside of the tank. For the float hole I cut an old radiator hose to just overlap the edges, placed a couple of large wahers, or jar lid if you don't have em, over it and clamped it down using an old electrical box light mounting bracket. It is just a short flat bar with long groves in it to allow adjustability. I used the OEM screws to clamp it down. For the pectcock hole I used the slide bar baseplate portion of a security chain door lock and some more radiator hose cut to size. Just drill a small hole in the hose for the OEM bolts and you will have a tight leakproof seal. You may have to use small washers here and there to make everything work. Don't laugh it works very well and didn't cost nuttin. And before you ask, for the gas cap opening I used a large cork plug. I happened to find a flat rubber gasket from an old jar lid that fit around the cork and sealed the opening pretty good. Good luck.

[GregM.]

Thanks for the detailed ideas on plugging large gas tank openings... exactly what I needed.

Regarding ball-bearings or nuts and screws... I don't have any old sealer in my tank - but I do have some kind of discoloration... probably rust eh?? I don't have any gas seeping out of seems... yet I have taken the tank off and poked around some on the seams, and all seems well.

Anyway I wondered if it would be worth the trouble swishing something around in the tank hoping to clean it up some, maybe get rid of the rust (if that's what it is) that's in there. I thought ball-bearings would be enough to do it... and they would pour out easily after.

Or should I do one of those muti stage treatments.

[FTGRET]

The POR-15 kit comes with a rust remover/prep solution that you use first.
I've done the tank on my 700 with the POR and it's going on 5 years without a weep.