Reverse Flushing Engine

Drain the cooling system. See Cooling - Standard Procedure . Remove the thermostat housing and thermostat. Install the thermostat housing. Disconnect the radiator upper hose from the radiator and attach the flushing gun to the hose. Disconnect the radiator lower hose from the water pump. Attach a lead away hose to the water pump inlet fitting.

CAUTION: Be sure that the heater control valve is closed (heat off). This is done to prevent coolant flow with scale and other deposits from entering the heater core.

Connect the water supply hose and air supply hose to the flushing gun. Allow the engine to fill with water. When the engine is filled, apply air in short blasts, allowing the system to fill between air blasts. Continue until clean water flows through the lead away hose. For more information, refer to operating instructions supplied with flushing equipment.

Remove the lead away hose, flushing gun, water supply hose and air supply hose. Remove the thermostat housing. See Cooling/Engine/THERMOSTAT - Removal . Install the thermostat and housing with a replacement gasket. See Cooling/Engine/THERMOSTAT - Installation . Connect the radiator hoses. Refill the cooling system with the correct antifreeze/water mixture. See Cooling - Standard Procedure .