imported post
I did my tank with por15, (
http://www.por15.com) seems to be working great. I cleaned the tank out with muriatic acid 80/20 solution strong. It cleaned out the tank within a few minutes. You have to plug the lines at the fuel **** port. Then release the plugs and let some acid run out to get the inside of the lines. Then put in some baking soda mixed with water and rise it out to stop the acid. Then IMMEDIATELY put in POR's prep solution. It will prepare the metal for the sealer and allow you to take your time in getting in. It has phosphoric acid in it which stabilizes the metal for a day or two..no rust. Then you pour in their sealer, slowly and careful into a part of the tank where it won't hit the screen intakes. If you do it slowly and careful you won't get any on them. Then SLOWLY rotate the tank until you've got it all covered. Again if you do carefully you can avoid any/most contact with the screens. I got the smallest can of both products the stabilizer is reusable. The sealer is not but I only put about half of the can in and it was still too much. I had to pour out about 2 oz. The less you can use the better as a deep coat or pooling is not good. I did seal up the fuel sensor hole using the locking ring and 4 layers of rubber. I painted some sealer on the sensor box later.
I would do this first! run your bike off a gas can for tuning etc. while you prepare the tank. You have to let this stuff dry for several days. Again be careful with how much you use less is more. The less you have to dump out the better as it's hard to get out because of the lip on the inside of the gas tank. Keep turning the tank until there is none of the sealer running around. If you put the tank down and let it sit for 30 seconds and look in with a flashlight you'll see the pooling if there is any..if there is start turn again or try to dump out the extra.
If you do get some on a screen you can try some compressed air through the fuel lines it may blow off the sealer.
Getting the tank out of your bike is a bit of a pain, the whole back end everything except the swing arm has to come off..and since you are that far you might as well take that off too and grease/clean the swing arm bearing etc. also change out the rear drive oil and re grease the splines with 60% moly...while you're at it.
OR
http://www.kawasakimotorcycle.org/forum/projects-how-write-ups/49040-help-rusted-gas-tank.html
or
take to a radiator shop have them boil it out and then seal it or nickel plate it..