1997 Johnson/Evinrude EU 25, 35 HP 3-Cylinder outboards Service Manual, Page 60Get this manual
Function Test
Two tests must be conducted to ensure proper fuel deliveryThe first test will check the suction pumps' ability to draw fuel from the fuel tankThe second test will check the pressure pumps' ability to supply fuel to the oiling unit and the carburetorsConduct these tests with the motor in test tank or on the boatBefore testing, loosen fuel tank gas cap momentarily to release any pressure that may have built upFuel tank must not be more than 30 in(76 cm) below fuel pumpSuction Pump Test
1Remove the fuel inlet fitting to suction fuel pump hoseConnect fuel vacuum gauge (obtained locally) between the fuel inlet fitting and the suction pump
2Start motor and run it at wide-open throttleObserve the gaugePump vacuum gauge should read no more than inches (102 mm) Hg3If fuel pump does not meet this specification, check fuel delivery system for restriction If no restriction is found, repair or replace the suction fuel pumpWhen installing new fuel pump, apply OIVIC Nut Lock to threads of screwsInstall screws and torque to 24-36 inIbs(2,8-4,0 Nm)Pressure Pump Test