I saw this done on youtube (or somewhere) and decided to give it a try. I had an old CT90 tank with a leaky bottom. I used a wire brush on the bottom and then a product called "seal all" and applied it to the the underside of the tank, particularly the seams. The was a noticeable hole in the tank that you could easily see through. So large in fact that the Seal All ran down on the inside of the tank. After I sealed it, it sat around until yesterday. It had been weeks. I've used Seal All before and it always seemed to retain a soft, spongy feel to it. Perhaps it's just because I added gas to the other tanks right away or perhaps it was because I didn't let it cure long enough but this application feels noticeably harder. I considered just adding gas and trying it but I decided against it. So on to the process.
I bought a "starter kit" for under $30. It comes with a small bottle of Marine Clean, Metal Ready, and 4 oz of sealant. I used a 2:1 solution of boiling water and Marine Clean to start. Then swished it around for a while and dumped it. It took a few rinses to get all the suds out. I used an old hair dryer and compressed air to dry it out. You'll notice an old CX500 valve cover is required for this step
Same sort of routine for the Metal Ready. I let it in there for about 25 minutes while I finished up some yard work. I shook it around every 5 minutes or so then rinsed and dried according to the instructions.
Then it was time to dump the sealant into it. I turned the tank around and upside down to ensure I got all the areas. I had trouble getting a coat on the metal baffle looking things in the tank. I ended up vigorously shaking the tank around a few times and got a good coat on everything.
I dumped out the excess back into the can. It looked to be about half full. I had to blow out the fuel feed holes on the tank every once in a while to keep them clear. It's at about 30 hours now and the sealant on the gas cap feels pretty hard. Definitely not scratching it with a fingernail. I'll try something sharper later. I'll probably let the tank go for a while as there is no rush. Then we'll see how it goes with gas in it.
