Agree with Martin.
If fuel pump is mechanical:
Take center wire off of distributor so it won't start. Run a hose from a good, clean gas can near front tire, on the ground, into pump inlet. Run the pump outlet into a container, like a water bottle. Crank motor. Should see pulsing good flow. If you get a good flow, hook tank hose back up and leave outlet into a bottle. Crank motor. If both test show good flow, it's the carb.
Good flow in these two tests eliminates:
1. Pump
2. Lines
3. Filter
4. Clogged tank pick up
5. Tank not venting
6. Tank gas level too low
Other results of these tests give great clues.
Before pump test, look down carb throat, motor off. Operate throttle, see if gas squirts out inside throat.
