2002/2003 Johnson SN/ST 2 Stroke 3.5, 6 8 HP Outboards Service Manual, PN 5005466, Page 119Get this manual
FUEL SYSTEM CARBURETOR CLEANING AND INSPECTION Start outboard and monitor gaugePump pressure must be as specified below:
RPM Pressure
600 2500-3000 4500
1 psi 1.5 psi 2.5 psi
7 kPa 10 kPa 17 kPa
CARBURETOR CLEANING AND INSPECTION
Cleaning
Carburetor must be completely disassembledUse clean bristle brush to remove gum or varnish depositsThoroughly clean components with Carburetor and Choke Cleaner
RESULTS If pump does not develop minimum pressure, replace the pump
Disassembly
Carefully, remove hoses from pumpLoosen screw and remove coverInspect cover and filter element for damage or debrisRemove pump to crankcase retaining screws
Assembly
When installing new fuel pump, apply Nut Lock to threads of screwsInstall gasket and screwsTorque screws to 24 to 36 inIbs(2.8 to 4.0 Nm)
IMPORTANT: Do not clean carburetor or its components by submerging in strong carburetor cleaner or hot soaking tankStrong cleaners might damage components or remove sealing compoundsFlush all carburetor holes and passages with small syringe filled with isopropyl alcoholBlow passages and carburetor dry with compressed air of not more than 25 psi (172 kPa)When drying passages, direct the flow of shop air opposite to the direction of fuel flow