Brazing on a Gas Tank

[DesertG]

I have no experience with welding or brazing. I have a vintage motorcycle gas tank that has a leak and also needs a couple studs attached.

I literally cannot find anyone in my area that could do this. I guess people that weld don't braze.

What am I missing.

 

[OccupantRJ]

That it is a gas tank and can explode or seriously change your world. It can be hot tanked, then welded or brazed, but that will bring it to bare metal with no paint left. If properly cleaned, the leak can be sealed with soft solder and a plumber’s torch. If the leak is a rust hole, there are likely more waiting that you are not aware of. Hot tanking will also expose this. Studs can be tig welded or brazed on. There are also specialty electric welding machines that can apply studs, but they are likely few and far between.

 

[DesertG]

Thank you. Nothing flammable to worry about. Yes, hot tank not an option. Can I solder over old brazing.

 

[The Cobbler]

soft soldering on brass is a yes , but as always parts need to be clean & fluxed .
solder won't hold your studs very well tho.

 

[dcg9381]

What am I missing.

TIG maybe? Small shop. No guarantee. No one at a big shop will weld a fuel tank.

 

[BigMike782]

Thank you. Nothing flammable to worry about. Yes, hot tank not an option. Can I solder over old brazing.

Nothing flammable to worry about?
It’s a brand new tank?
Even old tanks will cause some but pucker if you are not completely comfortable with them.
I agree with the other comments about chasing rust holes.

 

[Rusted Nut]

Wanting to have a couple of studs attached has my crystal ball saying you have an early '70 Bonneville tank. Yes? The studs are for the added tank strap to keep from splitting the original tank welds.

I used to work in a shop that serviced British bikes. I've rarely seen spot fixes on those tanks last; unless it's just around the petcock fitting, those can be successfully brazed. Go slow, heat from brazing or welding just accelerates the siamese weld separating. My advice would be to send the tank to a shop that specializes in repairing these things. No, it's not cheap.

 

[Jacko264]

If you want to solder don’t use a flame use the old type soldering iron that you heat in a fire or a flame
then clean the area tin it then solder

 

[lbhsbz]

No need to be scared of welding on fuel tanks....I've done plenty. Just clean them. I mix up some hot water and dawn dish soap and fill 'em about 1/2 way and shake 'em around for a bit, then dump it out. If you can't smell gas, then there's nothing to blow up.

If you want to be extra sure....get a 10' piece of something with a stick taped to the end of it and light the stick on fire....then wave it over the tank fill from a safe distance to test it. I've never had one do anything strange after cleaning it until the smell is gone.

 

[MagKarl]

After welding or brazing, I've had great success with this POR-15 kit on gas and hydraulic tanks.

Motorcycle Fuel Tank Repair Kit

POR-15's Motorcycle Fuel Tank Repair Kit has everything you need to seal your bike tank and protect from rust, corrosion, and seal pinhole leaks. Order now!

por15.com

 

[ng8264723]

I live in Ma. There was a guy in Dorcester that welded and brazed tanks all the time. He would do it with gas in them. The fumes burn not the gas. So his method was to take an exhaust hose and run it into the tank. Then fix the area. The exhaust is nonflammable