He's saying to replace the fuel pump.

If the filter was clogged initially, the fuel pump works hard to get the fuel to the engine, having to "suck" harder on the line to get the fuel through. This may cause the pump to fail prematurely, but you don't know this until you replace the filter and it still doesn't work right. While you may have restored the proper flow to the pump, it has already become worn out and it doesn't supply enough fuel to the engine.

The fuel line goes from the tank, to the filter, then to the mechanical fuel pump, unlike a fuel injected engine, where the fuel goes through a strainer, then to the electric fuel pump, then to the filter, then on to the engine.

John B.