I just installed a brand new fuel pump/sending unit combination in a 1987 Chevy truck TBI 5.7. The pump has less than 5 miles on it but i the truck has sat for a couple months after those 5 miles were put on it. I went to start it the other day and I did not hear the fuel pump turn on. Today I did some checks and it seems the fuel pump is locked up. When I run 12v to the pump directly from the battery the pump clicks but does not whirr to life and pump fuel. I really do not want to drop the tank again. I tried banging on the tank while clicking the fuel pump. I also tried clicking the pump a bunch without banging on the tank and it has not come back to life. What are some things I can try to get the fuel pump to start working again without dropping the tank?