Quote:
Originally Posted by bobcowan
The fuel pump does not control the pressure. It just pumps fuel. Pressure is created by restrictions after the pump.
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Bob,
I admit I don't know much about the design of mechanical fuel pumps, but it seems to me that the restriction you allude to is the float valve in the carb. The problem is that when the valve is closed the pump is powerful enough to raise the pressure above the target 5-7 PSI. My guess is that there is a spring controlled bypass valve at the pump that is supposed to open and release excess fuel back to the intake side of the pump. I consider that to be part of the pump, so by my definition the pump does control the pressure and the OP's pump is bad. .. True, a pressure regulator and return line can solve the problem, but so can a properly functioning fuel pump.