Suzuki outboard motors 1988 2003 repair manual., Page 204Get this manual
6-12 OIL INJECTION On most outboards, the water pump is mounted on top of the lower unitA driveshaft key engages flat on the driveshaft and notch in the impeller hubAs the driveshaft rotates, the impeller rotates with itOn the DT2 and DT2.2 the water pump is mounted in pump case installed on the propeller shaft between the lower unit and propellerThe pump impellers are secured to the propeller shaft by pin that fits into the propeller shaft and similar notch in the impeller hubThe propeller on other small displacement models is secured to the drive shaft in the same mannerSo what are major causes of overheating? Well the most prevalent cause is lack of maintenanceOther causes which are directly attributable to lack of maintenance or poor operating habits are: Fuel system problems causing lean mixture Incorrect oil mixture in fuel or problem with the oil injection system Spark plugs of incorrect heat range Faulty thermostat Restricted water flow through the powerhead due to sand or silt buildup Faulty water pump impeller Sticking thermostat
THERMOSTAT
See Figure 23
pellet-type thermostat is used to control the flow of engine water, to provide fast engine warm-up and to regulate water temperatures wax pellet element in the thermostat expands when heated and contracts when cooled The pellet element is connected through piston to valve When the pellet element is heated, pressure is exerted against rubber diaphragm, which forces the valve to open As the pellet element is cooled, the contraction allows spring to close the valve Thus, the valve remains closed while the water is cold, limiting circulation of water As the engine warms, the pellet element expands and the thermostat valve opens, permitting water to flow through the powerhead This opening and closing of the thermostat permits enough water to enter the powerhead to keep the engine within operating limits
REMOVALINSTALLATION