Auto body repair & detailing: fuel tanks, wast of time, gas tanks

Question
I am repainting my motorcycle.I bought new gas tanks.The store I bought them from recomends using a sealer before painting.I used Kreem in 2 other bikes but in time it all pealed off.Do you know of any other product for this?Do I even need to do this if the tanks are pressure tested and hold?The welds on the tank should hold forever if tested right?

Answer
You need to prime the steel with a self etching primer first. The wetsand with 600 wetordry sandpaper. Do not break through the primer ir you do you must reprime and sand again. Use a two part epoxy none sandable sealer. Any good brand like Dupont will do. Then paint. Dont forget too wash the bare steel first. Pressure testing as a wast of time I personally have never had a tank leak! When you do that operation you are stressing the tank to uneeded pressures.   
       Hope this helps.  

            Brian