Rudy wondered how to "rap" a fuel pump. The mechanic gave it a couple of sharp raps with his bare hand. Maybe he used knuckles. I suppose one could use a hammer. By the way, I've since been told by another mechanic that the fuel filter could have contributed to the problem. If fuel filter is dirty, pump has to work harder, leading to premature breakdown. So make sure you change fuel filters on schedule. Better a fuel filter than a pump, for sure.