My recently acquired 1970 Sportwagon that was converted to propane use is about to go back to gasoline. The tank has been unused for many years and has some funky varnishy stuff inside. It is not rusted out, just nasty looking inside. What is the best cleaner/conditioner/solvent to clean it out? I don't want to use a sealer kit as I have heard as many problems with peeling and flaking sealer and how clean you have to get them for the kit to work properly. Or is there a new tank option maybe? I looked online and the part number they list as a Sportwagon tank is also the tank for B-Body fullsized wagons. Can that be? Does anyone know their tanks? Thank you in advance.
When we have this problem on old farm tractors (Witch is every time you restore one) the first thing to try is to put some old nuts and bolts inside with rubbing alcohol. then it's like it says on the shampoo bottle lather rinse replete. Just roil the tank around and dump it out till it comes out clean. The other option is to find someone to hot tank it. Local radiator shop charges $100 for this.
Take tank out, plug all lines and fittings. Put about5 or 6 gal of E85 fuel in it. Put it back of your, or a buddies daily driver pick up and drive around for a week. Should do the trick. I just leaned this trick. worked great for an old boat tank for me. looked like new when dumped and rinsed.