🏷️ Basic Information Identification Make: Mercury Model: Mariner Outboard Variant: 40hp Marathon & Sea Pro Year Range: 1997 Onwards 📋 Manual Details Publication Manual Type: Service Repair Workshop Manual Language: English Format: PDF ⚙️ Engine Specifications General Engine Type: 2-Stroke Horsepower: 40hp Number Of Cylinders: 3 Bore: 90 mm (3.54 in) Stroke: 70 mm (2.76 in) Displacement: 1336 cc (81.5 cu. in.) Lubrication Oil Type: NMMA Certified 2-stroke Outboard Oil Fuel Mixture Ratio: 50:1 (Fuel:Oil) 🔧 Transmission Gearcase Gearcase Ratio: 1.83:1 (24:13) Gearcase Oil Type: Mercury High Performance Gearcase Lubricant 🔧 Maintenance Spark Plugs Recommended Spark Plug: NGK BUZHCS Spark Plug Gap: 0.035 in (0.9 mm) Fuel Filter Fuel Filter Replacement: As needed or annually Gearcase Oil Gearcase Oil Capacity: Approx. 280 ml (9.5 fl oz) 📄 Cooling System General Cooling Method: Water Cooled 📄 Ignition System General Ignition Type: CDI (Capacitor Discharge Ignition) 📄 Electrical System Charging Alternator Output: 10 Amps / 160 Watts 📄 Fuel System Carburetion Carburetor Type: 3 Carburetors 📄 Propeller Options Standard Propeller Pitch: Varies by application (typically 11" - 15")