Not too long ago I switched to the Jersey Modeler Pump system with 7.2 Volt battery after using a hand pump for years. Yesterday, I luckily noticed that my fuel system was not de-fueling correctly, and found out that my Sullivan header tank on my Kingcat had developed a small crack at the rear corner from the constant flexing of the tank when fueling/defueling. This could have cost me a flameout (and the airplane)-Do I remove a battery and run the pump on lower voltage or go back to the hand pump ? Opinions welcome. Thanks-Mike Oberst