Mythbusters proved that beach in a gas tank wont kill an engine... if that makes you feel any better. How much gas was in your tank when you parted it? If it was nearly full, then the ratio of gas to bleach isnt that much....see if you can find out the ratio of gas/bleach they used on the show and match it with how much gas you had to a gallon of bleach. If its near the same or lower, then you should be ok. The main problem with bleach in a gas tank is not the bleach itself getting into the engine, its that bleach will rust the inside of the gas tank VERY quickly. Might just want to go to the junkyard and get another gas tank... its about your only option now. Sorry to hear.