Fuel tanks cracking

I think you just have bad luck then. Honestly I would just layer some jb weld across them. We have a dump truck that got a hole through the bottom of a 100 gallon tank and we patched it with jb weld 4 years ago and it's been holding ever since.

 

Fuel tanks are aluminum so Im guessing thats why its still leaking after the jb weld.

 

You using the wrong kind. They make it for aluminum as well. Don't use the stick use the two part stuff in tubes. Squeeze it out and mix it together. Works great. It won't come through. Like I said I have it on the very bottom of a tank and it's been holding for years without a leak. Just make sure to sand it down well and use brake cleaner or alcohol to clean it off good.

 

Here's the bad side. I think your tanks are too big for the twisting. It is cracking along the weld. That means the rest of the metal is moving and flexing then the weld does not because weld is rigid. Then you have a long double bung in that spot. You could try to keep one strap tight and the rest snug. And then see how much the tank twists when you go in and out of all those holes you go through. But that tank will walk all over. So bring tools to get it back in place.