BOLT 6V5221 - Caterpillar

Clean the cooling system before the recommended maintenance interval if the following conditions exist:
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
Stop the engine and allow the engine to cool. Close the water inlet for the separate circuit aftercooler (if equipped). Ensure that the engine will not start when the cooling system is drained.
Pressurized System: Hot coolant can cause serious burns. To open the cooling system filler cap, stop the engine and wait until the cooling system components are cool. Loosen the cooling system pressure cap slowly in order to relieve the pressure.
Loosen the radiator filler cap slowly in order to relieve any pressure. Remove the radiator filler cap.
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(1) Coolant drainNote: If the engine has a jacket water heater, drain the coolant from the heater.
Open the coolant drain. Allow the coolant to drain.
Dispose of used engine coolant properly or recycle. Various methods have been proposed to reclaim used coolant for reuse in engine cooling systems. The full distillation procedure is the only method acceptable by Caterpillar to reclaim the used coolant.
For information regarding the disposal and the recycling of used coolant, consult your Cat dealer or consult Cat Dealer Service Tools:Inside U.S.A.: 1-800-542-TOOLInside Illinois: 1-800-541-TOOLCanada: 1-800-523-TOOLEAME phone: ++41-22-849 40 56EAME fax: ++41-22-849 49 29Clean the Cooling System
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.
After the cooling system has been drained, flush the cooling system with clean water in order to remove any debris.
Close the cooling system drain. Clean the cooling system drain plugs and install the cooling system drain plugs.
Fill the cooling system no faster than 19 L (5 US gal) per minute to avoid air locks.
Fill the cooling system with a mixture of clean water and Cat Fast Acting Cooling System Cleaner. Add .5 L (1 pt) of cleaner per 15 L (4 US gal) of the cooling system capacity. Install the radiator filler cap.
Open the water inlet for the separate circuit aftercooler (if equipped). Start the engine. Operate the engine for a minimum of 30 minutes with a coolant temperature of at least 82 °C (180 °F).
Stop the engine and allow the engine to cool. Close the water inlet for the separate circuit aftercooler (if equipped). 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.
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.
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