How hard is it to change a gas tank on a craftsman mower/walk behind. Asking for a friend that's unsure of age but he's had it for 3/4 years. Doesn't want to spend a lot, told him it's only maybe 20/30 $$$ and maybe 20 min time.

I wouldn't think is hard at all its just taking out bolts and screws.

My thoughts are why does it need changed?

Crack that started leaking on the backside of tank. Mower was used when he bought it. been good just started leaking from old repaired crack. To close to exhaust...