M60 Fuel Level Sensor

[Ferrett 1962]

My comment was more about the pump, with mine I removed and connected to a battery on it's own and it worked, I also wired it back up while still out of the tank and plugged the connector in and jumped the relay so I had constant power to it and the pump still ran. I was carefull to cover access to the open tank and make sure to vent the boot (trunk) and clear fumes, and not to run the pump while dry for too long as that will kill it. A mechanic I spoke to suggested using a container of fuel and holding the pump in it connect an outlet hose to direct flow and run the pump to see if will work under load. Set up right this could prove if the pump will pump the fuel, I didn't have a safe place to do this and thought the risk of fire was too high if done wrong but like you my pump worked out of the tank it could not build pressure at all under load and would fail. I left the pump and level sensor out in the air till the fuel evaporated before connecting the pump and wire harness, you would not have to jump the relay just turn on the key and if the pump runs like that the connection is ok the fault would have to be with the pump. If not I would do the relay jump just to eliminate this.