hello guys I'm new here, I have a customers 03 ranger 500 and the fuel pump only comes on for a second or two and then shuts off.  Turn the key off ,then on again and pump again runs for a second or two . It had one of the origional fuel pumps known to be defective or to fail, so, I replaced it and cleaned the carb.  I chose to eliminated the stock plastic fuel filter because the pro-flo #610-1050 came equipped with a 74 micron filter on the inlet side ...thinking all this  would solve the problem.  However, even with new fuel pump its still doing the samething. Ive checked for air leaks in the line and fittings and in the tank but to no avail.  I blew out the tank vent tube and it doesn't seem to be vapor locking, and pump is not getting warm.  I aslo checked for loose wires and oil is full.    what could be causing this? any help is appreciated