NOTE: Before performing this maintenance, determine the type of coolant that is being used. This maintenance applies ONLY to cooling systems that are filled with Caterpillar Extended Life Coolant (ELC).
Only clean water is needed in order to clean and flush the cooling system when ELC is drained and replaced.
Drain the Coolant
1. Stop the engine and allow the engine to cool. Loosen the radiator filler cap slowly to relieve any pressure. Remove the radiator filler cap.
2. Remove the cooling system drain plug(s) or open the drain valve. Open the cab heater valve to drain coolant from the cab heater. Remove the drain plug from the bottom of the water pump housing. Remove the drain plug from the bottom of the radiator. Allow the coolant to drain.
For information regarding disposal and recycling of used coolant, call the Caterpillar Service Technology Group:
Outside Illinois: 1-800-542-TOOL
Inside Illinois: 1-800-541-TOOL
Flush the Cooling System
1. Flush the cooling system with clean water to remove any debris.
2. Clean and install the drain plugs. Close the drain valve.
3. Fill the cooling system with clean water. Install the radiator filler cap. Operate the engine until the jacket water temperature reaches 49 to 66°C (150 to 120°F).
4. Stop the engine and allow the engine to cool. Loosen the radiator filler cap slowly to relieve any pressure. Remove the radiator filler cap. Remove the cooling system drain plugs. Open the drain valve. Allow the water to drain. Flush the cooling system with clean water.
5. Repeat steps 3 and 4.
Fill the Cooling System
1. Install the drain plugs. Close the drain valve. Fill the cooling system with ELC. Refer to the Refill Capacities chart for the amount of ELC needed to refill the cooling system.
2. Start and run the engine with the radiator filler cap removed. Allow the ELC to warm, the water temperature regulator to open, and the coolant level to stabilize. Add ELC if necessary in order to bring the coolant to the proper level.
3. Check the condition of the radiator filler cap. If the gaskets are damaged, replace the old radiator filler cap with a new radiator filler cap. If the gaskets are not damaged, pressure test the radiator filler cap with a 9S-8140 Pressurized Pump Group (available from your Caterpillar dealer). The correct pressure is stamped on the face of the radiator filler cap. If the radiator filler cap does not hold the correct pressure, install a new radiator filler cap.
4. Start the engine. Inspect for coolant leaks and proper operating temperature.