[porwolf]

I replaced my 79 SC Bosch fuel pump a couple of years ago because the original pump was frozen because of stale gasoline when the care was stored for many years. Because of possible old fuel debris still left in the tank I replaced it with a $ 50.- Walbro pump. That pump initially was very noisy. I don't remember hearing anything from the original Bosch pump before I put the car into storage. But now, even the new Walbro pump is quiet. Especially with a full tank of gas. Because of the Techron gas additive I only use Chevron gas now. I think That eventually cleaned out the fuel system and keeps the pump quiet. I understand cavitation can cause fuel pump noise and cavitation can be caused by restricted input to the pump. The pump, I understand, transports a lot of fuel, more than the engine needs, the rest goes back into the tank.