Mercury 9.9hp 4-Stroke – Specifications

Engine

• Horsepower: 9.9 hp (7.3–7.4 kW)
• Engine type: 4-stroke, 2-cylinder (SOHC)
• Displacement:
  • EFI models: 208 cc
  • Older variants: up to 323 cc
• Bore x stroke: ~55 × 44 mm (EFI)

Performance

• Full throttle RPM: 5000–6000 rpm (EFI)
• Fuel system:
  • EFI (Electronic Fuel Injection) or
  • Carbureted (older models)
• Ignition: Digital CDI with electronic spark advance

Fuel & Cooling

• Fuel type: Unleaded 87 octane
• Fuel tank: External 12L / 3.2 gal
• Cooling: Water-cooled with thermostat

Dimensions & Weight

• Weight:
  • Light EFI models: ~38–41 kg (84–91 lb)
  • Heavier variants: up to ~50 kg
• Shaft lengths: 15” (short), 20” (long), 25” (extra-long)

Drive & Controls

• Gear shift: Forward – Neutral – Reverse
• Gear ratio: ~2.08:1 (EFI)
• Steering: Tiller or remote
• Starting:
  • Manual pull start
  • Electric start (some models)