OMC Stern Drives And Motors 1964-1986 Repair Manual., Page 24Get this manual
NAVIGATION not run, disconnect the leads the motorConnect the leads and see if voltage is indicatedIf voltage is indicthen the problem must in blown fuse, defective switch, some the of the electrical systemIf the indicates voltage is present at the leads, then remove, disassemble, and inspect the bilge pumpCleanreassernble, connect the leads, and the switch againIf the motor still fails run, the pump must be replacedT the bilge pump switch, first disconnect the leads fro-n the pump and connect them test light ohmmeterNext, hold the switch firmly against the mounting location in make good groundNow, the opposite end of the switch upward until is activated as indicated by the light coming on the showing continuityFinally, lowe the switch slowly toward the mounting position until is deactivatedMeasure the between the point the switch was and the point was deactivatedF proper service, the switch should -
i between 112-inch and l4-inch from the planned mounting positionCAUTION: The switch never be mounted lower than the bilge pump pickup