Once rust gets established in a tank it spreads like weeds in a lawn. Not looking in the tank while refueling can only be described as denial. Until recently, treating the rusty interior of tank with a tank liner kit was the only remedy. While tank lining is an effective rust removal and prevention system, two concerns have led home mechanics to fear the process. First, the rust is removed with an acid that eats the oxidized metal. Unfortunately, the acid also dines on good metal and paint. Disposing of the acid poses another problem. Finally, if the directions for the acid etching and the application of the lining material are not followed to the letter, the liner may, at some point in the future, peel away from the tank interior, causing other problems.