Two-stroke versus Four-Stroke

• Your choice of a two-stroke or a four-stroke outboard motor depends largely on the type of boating that you want to do. Offshore, where high acceleration is needed, a two-stroke motor may be the better choice. For more leisurely activities, such as fishing inshore, a four-stroke engine may provide a smoother ride.
  
  

Cooling

• Cooling of an outboard motor is achieved by drawing water up directly from the sea or other water course by an impeller pump. The water passes through the motor and out through the exhaust. The temperature of the engine is monitored via a thermostat and, in some cases, visible and audible alarms are fitted.
  
  

Lubrication

• Two-stroke outboard motors are lubricated by mixing oil with gasoline in the fuel tank. Four-stroke outboard motors are lubricated by oil circulating from the sump or crankcase. In either case, too little oil will cause the motor to overheat and eventually seize, while to much will cause smoky exhaust fumes and heavy deposits of carbon.