Muz,
This is a split in a diesel fuel tank on the pajero. it looks like where the baffle is welded to the skin its tearing the skin. the right weld is where the leak is. It's not growing any more and i will be welding it tomorrow. I was going to weld along the split and T it at each end of the split, then weld some 3mm plate over the area of both welds and plug the extra plate every 4"(just a 5mm hole).
What do you think?