The outlet pipe at the bottom of the gas tank came with a roll of screen sticking out of end of the pipe. They usually aren't there 70 later.
So you will be left with noting to keep a sizable flake from sloshing around in the tank and occasionally covering the top of the down pipe, causing an intermittent fuel blockage.
It is difficult to confirm that this is happening, unless you disconnect the fuel line to check proper flow at the very time the errant flake is there blocking the pipe.
If the engine starts after sitting for a while, that could indicate that the flake is only partially blocking the flow, and enough fuel eventually slips by allowing gravity to re-establish enough fuel flow to start the engine and it will run for a while.
