The Perry VP-20 will probably be what you are looking for. It is the oscillating type of pump that mounts to the back plate of your engine, and works off the engine vibration. I have this pump installed on 2 4-stroke engines (a Saito 1.50, and an Enya .90), and it works well. In both of my situations the engines are mounted inverted, and I could not change the fuel tank location.

Perry makes other pumps that require a pressure tap from the motor, but I have never tried them.

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