Okay, that’s the one I thought you were going to say needed a cleaning. Older tanks need to get thoroughly cleaned out as part of the restoration process. Even if that dude hadn't misrep'd, you might have still wanted to do this.
The stuff for older tanks is
Kreem. There are a couple other treatment kits out there, but I’ve used Kreem half a dozen times and it’s worked perfectly each time. It’s a two or three step process:
The first is an acidic treatment. You have to mix it with water (about two gallons) and it’s strong as shit. Wicked fumes and throws off pressure, so
you want to seal the tank well and do not fill the tank; go half or even a third full for this stuff or it’ll blow out whatever you’ve got plugging the fill and petcock holes. Also, it will eat up any rubber gaskets, so you need to find something to plug the holes. Since it’s an older tank, drop in a dozen or so bolts to slosh around with the acid mix to knock off any flakes. Alternatively, I’ve used muriatic acid, which you can get at Pinch-a-Penny; same stuff that goes in the pool. It’s not as strong as the acid in Kreem though and I once had to leave it in overnight. The Kreem acid works in minutes. You'll hear it sizzling in there.
The second is the etch. The etch coat goes in right after the acid is flushed out with a high pressure hose, and seals the metal from further rust. This step needs to happen fast, because
the inside of the tank will flash rust if it doesn’t get etched quickly. Trust me on this; it’s got to happen like immediately. Drain the water out…pour the etch in and slosh it around quickly. If it does flash rust on you, don’t worry about it, just start over. Both the acid mix in step one and the etch can be used about half a dozen times, so don’t toss it until you’re totally satisfied that you got the rust out and have it properly etched. If you go the muriatic route, you still need to etch. Autozone has this stuff called Rust Bandit that does the job.
The third step is the coating or liner. Its white goo that you slosh around inside the tank and it dries hard. You need to make a decision to use this stuff. You may not have to. Generally, it’s a good idea to use on older, rusted tanks because it’s a solid liner. It takes care of any pinholes, or potential pinholes, and firms up the tank if you flushed a ton of rust out. Your call; this is one messy freaking step. I don’t even know how to describe this stuff except it’s close to Fluffer-Nutter
and just about that consistency. Honestly, I try and avoid it, but if you think the tank needs it then go with it.
Overall, this process is going to destroy the paint on the outside of the tank. The instructions guide you on how to avoid that, but I’m telling you…you can’t. So hopefully you haven’t put any paint on the tank yet. If you did, you’re repainting.
Cycle Gear has Kreem on the shelf for $40, for the three stage kit. You can get the acid and etch separately if you don’t want to go the liner route, or you can do the muriatic and Rust Bandit Route, which is a little more effort on the cleaning side.
