3512C HD Locomotive Engine Caterpillar

• The engine overheats frequently.

• The coolant is foaming.

• Oil or fuel has entered the cooling system and the coolant is contaminated.

Drain the Cooling System

1. Stop the engine and allow the engine to cool. Close the water inlet for the separate circuit aftercooler. Ensure that the engine will not start when the cooling system is drained.

2. Loosen the radiator filler cap slowly in order to relieve any pressure. Remove the radiator filler cap.

   Note: For the location of the coolant drain, see the service literature that is provided by the OEM of the locomotive.

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   Illustration 1	g00831734
   Location of the cooling system drain plugs (1) Oil cooler (2) Jacket water pump (3) Cylinder block

   Note: If the engine has a jacket water heater, drain the coolant from the heater.

3. Open the coolant drain. Remove cooling system drain plug (1). Remove cooling system drain plug (2). Remove cooling system drain plug (3). Allow the coolant to drain.

For information regarding the disposal and the recycling of used coolant, consult your Caterpillar dealer or consult Caterpillar Dealer Service Tools:

Clean the Cooling System

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NOTICE
Use of commercially available cooling system cleaners may cause damage to cooling system components. Use only cooling system cleaners that are approved for Caterpillar engines.

1. After the cooling system has been drained, flush the cooling system with clean water in order to remove any debris.

2. Close the cooling system drain. Clean the cooling system drain plugs and install the drain plugs.
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   NOTICE
   Fill the cooling system no faster than 19 L (5 US gal) per minute to avoid air locks.

3. Open the water inlet for the separate circuit aftercooler. Fill the cooling system with a mixture of clean water and Caterpillar Fast Acting Cooling System Cleaner. Add 0.5 L (1 pt) of cleaner per 15 L (4 US gal) of the cooling system capacity. Install the radiator filler cap.

4. Start the engine. Operate the engine for a minimum of 30 minutes with a coolant temperature of at least 82 °C (180 °F).

5. Stop the engine and allow the engine to cool. Close the water inlet for the separate circuit aftercooler. Ensure that the engine will not start when the cooling system is drained. Loosen the radiator filler cap slowly in order to relieve any pressure. Remove the radiator filler cap. Open the coolant drain. Remove the cooling system drain plugs. Allow the water to drain.
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   NOTICE
   Improper or incomplete rinsing of the cooling system can result in damage to copper and other metal components. To avoid damage to the cooling system, make sure to completely flush the cooling system with clear water. Continue to flush the system until all signs of the cleaning agent are gone.

6. Flush the cooling system with clean water until the water that drains is clean. Close the coolant drain. Clean the cooling system drain plugs and install the cooling system drain plugs.

Cleaning a Cooling System that has Heavy Deposits or Plugging

Note: For the following procedure to be effective, there must be an active flow through the cooling system components.

1. After the cooling system has been drained, flush the cooling system with clean water in order to remove any debris.

2. Close the coolant drain. Clean the cooling system drain plugs and install the cooling system drain plugs.
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   NOTICE
   Fill the cooling system no faster than 19 L (5 US gal) per minute to avoid air locks.

3. Open the water inlet for the separate circuit aftercooler. Fill the cooling system with a mixture of clean water and Caterpillar Fast Acting Cooling System Cleaner. Add 0.5 L (1 pt) of cleaner per 3.8 to 7.6 L (1 to 2 US gal) of the cooling system capacity. Install the radiator filler cap.

4. Start the engine. Operate the engine for a minimum of 90 minutes with a coolant temperature of at least 82 °C (180 °F).

5. Stop the engine and allow the engine to cool. Close the water inlet for the separate circuit aftercooler. Ensure that the engine will not start when the cooling system is drained. Loosen the radiator filler cap slowly in order to relieve any pressure. Remove the radiator filler cap. Remove the cooling system drain plugs. Open the coolant drain. Allow the water to drain.
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   NOTICE
   Improper or incomplete rinsing of the cooling system can result in damage to copper and other metal components. To avoid damage to the cooling system, make sure to completely flush the cooling system with clear water. Continue to flush the system until all signs of the cleaning agent are gone.

6. Flush the cooling system with clean water until the water that drains is clean. Close the coolant drain. Clean the cooling system drain plugs and install the cooling system drain plugs.

Fill the Cooling System

Note: For information about the proper coolant to use, see Special Publication, SEBU6251, "Caterpillar Commercial Diesel Engine Fluids Recommendations". For the capacity of the cooling system, see this Operation and Maintenance Manual, "Refill Capacities and Recommendations" (Maintenance Section).

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NOTICE
Fill the cooling system no faster than 19 L (5 US gal) per minute to avoid air locks.

1. Fill the cooling system with antifreeze/coolant. After filling the cooling system, do not install the radiator filler cap.

2. Open the water inlet for the separate circuit aftercooler. Start the engine. Operate the engine in order to purge the air from the cavities of the engine block. Allow the coolant to warm and allow the coolant level to stabilize. Stop the engine.

3. Check the coolant level. Maintain the coolant to the proper level on the sight gauge (if equipped). If a sight gauge is not equipped, maintain the coolant within 13 mm (0.5 inch) below the bottom of the filler pipe.

4. Clean the radiator filler cap. Inspect the gaskets of the radiator filler cap. If the gaskets of the radiator filler cap are damaged, discard the old radiator filler cap and install a new radiator filler cap. If the gaskets of the radiator filler cap are not damaged, use a 9S-8140 Pressurizing Pump in order to pressure test the radiator filler cap. The correct pressure is stamped on the face of the radiator filler cap. If the radiator filler cap does not maintain the correct pressure, install a new radiator filler cap.

5. Start the engine. Inspect the cooling system for leaks and for proper operating temperature.