are you sure Ron, back when I knew nothing about esc's or anything else for that matter(I was 14). I had recently lit my villain IV on fire after installling my trinity midnight motors. I decided to put a fuse in, along with heavy gauge wire. Now mind you were talking twin modified car motors, on a single esc and I used a 30amp fuse. I never blew the fuse. I'm surprised actually, in fact I just dug that fuse out of one of my toolboxes, yep 30amp. I had the fuse hooked up to the y-harness on the battery packs. Am I calculating this wrong, anyways just questioning the 30amp thing.

Also, it has to be the batteries, if they dont work in your cars and they dont work in the boat then.......
I mean ok it could be the charger, but dont you have one of those cheap wall plug chargers laying around you could try, to make sure. I've got like 5 of them from various rc vehicles. Also if you dont have a multimeter go out and buy one, you dont need to spend a lot on it, just get a decent one. I'm betting you have a bad cell or cells. Just check the voltages like someone else said. In the mean time get a new pack. An esc wont set you too far back, heck you can get BL esc's for like 50$ now.