Square Oil Tank Repair

[drinner-okc]

Working on a 65 ElectraGlide with what we want to believe is the original Oil Tank, & Owner wants to repair & use if possible.
Symptom was a small drip from the Drain Plug, even if the bike was not ridden. A new washer & dressing the surface with a soapstone did not help.
The bike has been down all winter for multiple repairs, repaint, rechrome. Yesterday we were cleaning the Frame & remaining assembled items by hand, to start reassembly.
There was a droplet on the drain plug, even though there was NO OIL in the tank,
The lines have been replaced & not refilled yet.
We removed the Tank, looped the Supply Line to the Return Fitting, and hooked up the Air Pressure Regulator from my Manifold Testing Kit to the Vent. Pressurized to 10-psi & Viola! (or Wah-Lah, depends where you live..) It made Bubbles.
The bottom bracket is attached by multiple spot welds (8-10?) Looking inside one of the Spots has started a crack, maybe 3/8" long now.
I need recommendations for a one-time fix.
A good cleaning & POR-15 is one choice, but the crack would continue & maybe leak in the future.
Maybe we could focus a small torch tip on the outside & get enough heat to braze over the crack. But once we try brass we could never electrical weld.
Have someone with a mill bore just thru the bracket & TIG the crack. Then maybe fill the hole with filler metal & grind flat & repaint that area? Would that much heat spawn more cracking?
Any Used Tank off E-bay might leak just as bad, or worse.
I'll watch the forum for sugestions, Thanks, drinner

[Bigincher]

So.... you're saying the tank is cracked underneath the bracket, so you don't have direct access to the crack itself?
Anything you put in the oil tank could end up in the motor--- a sealer would not be a wise choice, in my opinion.
Brazing seems like a second-rate choice, as well. I've seen brazed cracks do fine for a period of time, but the crack returns.
If it was mine, I'd remove the portion of the bracket that is blocking access to the crack, and have an expert Tig welder repair the crack.
Then do whatever cosmetics need to be done where the portion of bracket was removed.
You mentioned a milling machine to remove part of the bracket. Would a steady hand with a die grinder do as well?
Hard to visualize without photos.....

[Dinuns1]

Very Common for them to crack under that bracket ,the only ''right'' way to repair it is remove the bracket repair crack and reinstall bracket .Pm me if you want to change the tanks i have a 65 one in my pile of parts i will never use . I would trade for other pan parts.

[Budster 95]

Remove the bracket, drill small holes at each end of the crack, then tig. The drilling of the holes provides a radius at each end of the crack to stop the crack from spreading.

[drinner-okc]

I have a 70 & later tank (has the dipstick) and the bracket is simply skip welded along the edges. A cut-off wheel would easily cut the weld. The early tanks had 10 or 11 spot welds along the perimiter and getting it off would be tough. Then all the heat putting it back on would be hard on the tank.
john HD recommended silver solder on the Panhead site. That might be the most unobtrusive repair.

I offered the use of my 70's tank, but the owner wants to keep the bikes original parts.