OMC Stern Drives And Motors 1964-1986 Repair Manual., Page 34Get this manual
FUEL SYSTEM t diaphragms and not out of the pumpIf gasoline is detected in the sight gauge, means the pump is defectiveIf the dual-diaphragm becomes defective any reason, must be replacedDo not repair this type of pumpCarburetor Adjustment Decause the carburetor is required accurately control and mix the air and fuel quantities entering the combustion chamber, proper adjustments critical efficient engine operationDirt and gum in the passages restrict the flow of air fuel causing lean operating condition; hesitation on acceleration; and lack of power on demandThe carburetor control linkage is subject wear which will change the synchronization and fuel mixtureThese changes will engine performance and fuel economyTherefore, carburetor adjustments can hardly be made or expected if the carburetor is not in satisfactory conditionIf considerable difficulty is encountered in making the adjustments, the remedy may carburetor overhaul, see Chapter 4T make preliminary adjustment, turn the idle mixture adjusting needles inward until they BARELY make contact with their seats, then back the needle the specified number of turns