1978 Evinrude Outboards 9.9/15HP Service Manual, Page 27Get this manual
TESTING FUEL PUMP Conduct this test on the motor in test tank or on the boataRemove carburetor to fuel pump hoseConnect fuel pressure gauge between the carburetor and fuel pumpNOTE Before testing, loosen fuel tank gas cap momentarily to release any pressure that may have built upFuel tank must not be more than 24 inches (610 mm) below fuel pumpbstart motor and observe gaugeshould read as belowRPM 2500 to 3000 1.5 PSI (10 kPa) Pump pressures
It is recommended that new fuel filter gasket be installed when servicing the filter and pump assembly
600 PSI (7 kPa)
4500 2.5 PSI (17 kPa)
FUEL PUMP AND FILTER REMOVAL