Leaking bulk tank question

[M.MacKenzie]

I have a leaking 300 gallons ss bulk tank. It will drain to about the final few inches. It leaks much more quickly when it is full and slows as the head is lost. I am unable to tell from where it leaks. The sap drips appear at the the bottom outside edge, so it is coming from somewhere between the insider liner and the outside cover. Does anyone have suggestion of how to determine where the actual leak is and a suggestion of how to seal the tank?
Thank you.
Malcolm

[maple flats]

Try cleaning the tank and then get in the tank. You should be able to find any possible leak. Best to weld it, but there might be accepted patches for food contact. Check closely any seams, they will be most likely the spot, and also any dings or other flaws in the surface.

[wmick]

If you fill with water and let it leak till it stops... you should be able to mark the level of the leak... and start searching...
I would recommend getting someone to tig weld it for you. If it is a stress crack starting, it might only get worse over time, if not welded.

[Bucket Head]

Does the outside shell have a small condensation drain hole on the bottom, at the outlet end? Do you have a compressor and a blow gun with the cone-shaped rubber nozzle at the end? If so, maybe you could fill it with water and put just a little pressure in between the liner and the shell and then watch for bubbles?

Just thinking out loud here. Other than that, your going to have a tough time trying to find a fine stress crack. Not impossible, but tough.

Might be worth a shot. Let us know what happens.

Steve

[wmick]

Awesome idea, Buckethead... I hadn't thought about the shell being airtight enough to hold some air pressure.. But if it is, that's the ticket..

[M.MacKenzie]

Thanks to all of you who have responded. I think it is a stress fracture as it leaks more when it is a colder temperature which may be due to slight contracting of the metal.