Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Do you have fuel flowing to the inlet ofthe carburetor? If you do, you likley have debris from old fuel line ,lodged in the needle valve passage, clogging the needle valve. You would need to remove the float bowl and the needle valve and float and the inlet line, and blow back toward the inlet, to clear any debris.
Fuel line from tank to the fuel pump inlet has to be vacuum tight, and the P line(pulse) line from the crankcase has to be on the P port of the fuel pump or pump does not work.
Both should be fine, as long as they fit. Is the fuel pump hooked up correctly?
If you remove line at the carburetor and at the line you installed, and hold finger over the hose while you suck on it, is the hose vacuum tight? It should be. But if there is a tiny leak, it will not hold vacuum. Next would be to test the line from fuel filter to the tank.
Everything before the fuel pump has to be vacuum tight. You say fuel filter is empty, so the fuel pump is not sucking. That indicates that there is a leak in the vaccum side. Everything after the fuel pump is under pressure. ???
What is the application? Is the fuel outlet in the tank from the top or the bottom of the tank? Deere uses a top tube, and it has to be vacuum tight?
Quick test would be to make test line direct from the pump inlet line, into another fuel container, to see it it will suck fuel and start engine. If it does, you know the tank or lines to the pump are plugged or leaking vacuum.
Good Job! Please rate in a positive manner and that will close the question and get me credit! Thanks.