When is a tank too far gone?

[GregT]

How about doing Oakum and lead sealing on cast iron sewer pipes?? Yup Ive done lots of that too.

I bronze weld broken fins on cast iron cylinders - not hard with the right flux.
And yes, you can bronze with uncoated rod but if you want it to "tin" properly on old pressed steel, I would always use flux.

[chuck hahn]

Best thing about Gregs tank is that hes gonne be doing a liner kit AND the fact its out of sight on the bottom. So..he can get it good enough to be sealed ( doesnt have to be real pretty ). Good enough to hold the cleaner solution is good enough..then do the liner kit and he will never have to worry about it again.

[Nessism]

With a hole that size there is a very good chance there are various other places on the tank with thin metal as well. It's very difficult to derust such a tank because it won't hold fluid. Maybe submerge the entire tank and try electrolysis? Maybe some metal prep, a couple three gallons, in a small garbage can? One way or another it's best to derust to some extent before making the patches.

Silver brazing alloys melt at a lower temp than brass so you have less heat distortion that way. I'd use the correct flux then plan on soaking the tank afterwards in hot water to clean. You can always go back into the phosphate sauce if some flash rust shows up.

It's going to be next to impossible to braze closed all the various holes that are likely to show up. Best tend to the larger holes then use Caswell's Epoxy sealer (which is thicker than honey and helps reinforce the metal).

Not a fun project, but doable.

Good luck

[Gregory]

maybe I should just caswell the inside AND the outside

[rustybronco]

Nope, just weld in new metal. No matter what you use to reline the tank, you need structural integrity before hand.

[silverhorse47]

Or just sand by hand thoroughly, then solder in with lead solder with an iron.
You can go all ape **** on it and cut, weld, braze and etc., but the safest way is just to clean it off with sandpaper, then use an iron to solder over the pin hole.

S.

[ohiocaferacer]

I just repaired my 78 GS1000 skunk tank last summer. You can read about how I did it here:

http://www.thegsresources.com/_forum/showthread.php?p=2042174#post2042174

Dont try and do any welding or brazing on that tank, it will only get worse. I'm experienced at welding tanks(steel and aluminum) and tried to tig weld mine first. Didnt work as the metal is so thin.....would just blow through and make a bigger hole. Also...the rust inside the tank contaminates the weld. Just put some duck tape over the holes and use the Caswell tank liner kit. I duct taped the entire bottom and part of one side of my tank. Follow the instructions. Mine came out perfect and has held a full tank of gas for the last year, with no issues.

[oldgrumpy]

when is a gs tank toooo far and not worth fixing,,,

hi guys ,,,unfortunately i fell for fixing my first gs1000 tank 1980 model,,, i fell for letting a retired boiler maker aged 72,, he actually had a fab business in morwell well the left side of the tank which included the seam was plated with2mm plated he formed sort of ,,,and around the seat seam looked crap heavy welding my tank ended up looking like the titanic ,,,it still sits under my current garage work bench,,,,, my second gs1000 tank had some pin hooles along the left seam 2-3 not big and a couple around the seam near the seat,,, so i welded it up with tig,,, and sprayed it hot red ,,,,thats also sitting under the bench with the fuel cap hole taped and the petcock hole taped ,,, i currently have a vgc... red /white 1980 gs1000s gen.tank from western australia,,, thats currently on my bikei,m looking at maybe spraying that or at least a spray painter in bordertown is going to spray it in 2 pac with clear over to finish he,s a very good painter and panel beater regards oldgrumpy

[chuck hahn]

Ohiocaferacer....Really..cant weld on it and your an experienced welder?? Better check out a thread here. I MIG welded it all up and the holes were the size of thumb nails. Then soldered over to be sure any micro pinholes were sealed.....

http://www.thegsresources.com/_forum/showthread.php?t=192039&highlight=Cooley+tank+saved

[ohiocaferacer]

Ohiocaferacer....Really..cant weld on it and your an experienced welder?? Better check out a thread here. I MIG welded it all up and the holes were the size of thumb nails. Then soldered over to be sure any micro pinholes were sealed.....

http://www.thegsresources.com/_forum...ley+tank+saved

Chuck....thats great.....you must be a talented welder.
Based on the OP and his issues related to welding the bottom(not top) of his tank, that metal from where it has rusted out gets thin....at least it was on my tank. When the metal is tissue paper thin, once heat is applied it burns like a tissue in a flame. Since he is already having issues with burn through, trying to share my experience with my tank. Not looking to flame anyones skills or talents, just trying to help.

[chuck hahn]

True.,..and I also suggested he cut it out to the point there is good solid metal again and braze a patch over the hole. I have welded on metals as thin as 21/1000 all my life ( 24 years of it anyway ) as a Steel Rule Die Maker back in Detroit. It takes some crazy control and patience but its very doable.

That being said..Even I am not skilled enough to MIG that hole shut... Its gonna take a patch. Good thingb its on the bottomk..no concerns for asthetics there.

[Gregory]

I haven't played with the hole yet, but went looking at Lowes for something to dip the tank in to eat all the rust on the inside of the tank but didn't have any luck.

Is there anything cheap out there that I could fill a tub with to soak the tank in?

[ohiocaferacer]

I used about 3 jugs of this stuff from Home Depot.


Filled a large storage tote with it and set my tank down in it to soak for a few days. Holes in bottom of gas tank allowed prep/etch to fill into tank. I put some drywall screws inside the gas tank and would shake it around every now and then.


Took about a week to clean it all out.

[Gregory]

Thanks Greg. I had see that from you on another post and was looking for it at Lowes. ... I will call Home Depot now.

I used about 3 jugs of this stuff from Home Depot.


Filled a large storage tote with it and set my tank down in it to soak for a few days. Holes in bottom of gas tank allowed prep/etch to fill into tank. I put some drywall screws inside the gas tank and would shake it around every now and then.


Took about a week to clean it all out.

[chuck hahn]

Thats what i have used before and its a strong Phosphoric acid...I dilute it 50/50. MONITOR IT CLOSELY and then a wash with baking soda inside and out to stop the acids corrosive effects.

Rinse well and dry it immediately. I use my heat gun down the filler neck and dry it as fast as I can. Then do the liner. Best to have everything on hand and go from step to step and get it done before flash rust takes root again.