Flush Cooling System and Replace Thermostat

For efficient operation, drain old coolant, flush the entire system, replace thermostat, and fill with clean antifreeze solution at least once every 2 years.

causym CAUTION: DO NOT remove radiator cap or drain coolant until coolant is cold (temperature gauge should be below the green striped zone). Always loosen radiator cap or drain cock slowly to relieve any excess pressure.

1. Drain coolant - Remove radiator cap (A). Open drain valve (B) on radiator and drain coolant from radiator. Open drain plug (C) on left side of engine block and drain coolant.

IMPORTANT: Thermostat must be removed to insure a thorough flush.

2. Remove thermostat - Remove thermostat cover (D), remove thermostat, and re-install cover (without thermostat). Tighten cap screws to 47 N·m (35 lb-ft).

3. Flush system with water - Close all drain valves/plugs and fill system with clean water. Run engine about 10 minutes to stir up possible rust or sediment. Stop engine and drain water from system before rust and sediment settle.

4. Flush system with Radiator Cleaner - Close all drain valve/plugs and fill the cooling system with a good commercial radiator cleaner and water. Follow instructions provided with cleaner. Run engine until it reaches operating temperature. Stop engine and immediately drain system.

5. Flush system with water - Close all drain valves/plugs and fill with clean water to flush the system. Run the engine about 10 minutes, then drain out flushing water.

M47129
M47130
AT1159
AT1180

AT,5SOM,154 -19-15JAN97-1/2

6. Replace thermostat - Remove thermostat cover (D) and clean off the gasket material. Apply gasket sealant to new gasket and install along with new thermostat. Tighten cap screws to 47 N·m (35 lb-ft).

7. Fill with fresh coolant - Close all drain valves/plugs and fill with specified coolant (see Section "Fuels, Lubricants and Coolant").

8. Re-check coolant level - Fill radiator to the top of the filler neck and fill the recovery tank to the "LOW" mark. Run the engine until operating temperature is reached. Let the engine cool (preferably overnight) and recheck the coolant level. Coolant level with a cold engine should be at the "LOW" mark. An engine at operating temperature should have a coolant level at the "FULL" mark. When refilling the cooling system it may require several operating/cooling periods to stabilize the coolant level in the system. Add make-up coolant to the recovery tank as needed to bring the coolant level to the correct mark.

AT1180

AT,5SOM,154 -19-15JAN97-2/2