GASKET 3725946 - Caterpillar

Drain the Cooling System
Stop the engine and allow the engine to cool. Ensure that the engine will not start when the cooling system is drained.
Loosen the cooling system filler cap slowly in order to relieve any pressure. Remove the filler cap.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Illustration 1 g00622312
Coolant drain under the jacket water heater
Illustration 2 g00622336
Location of the cooling system drain plugs
(1) Exhaust elbow
(2) Oil cooler
(3) Jacket water pump Note: Open the coolant drains under the jacket water heaters. Remove the cooling system drain plugs. 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 Caterpillar dealer or consult Caterpillar Service Technology Group:Outside U.S.A. (309) 675-6277
Inside U.S.A. 1-800-542-TOOL
Inside Illinois 1-800-541-TOOL
Canada 1-800-523-TOOL
CSTG COSA Geneva, Switzerland 41-22-849 40 56
Clean the Cooling System
After the cooling system has been drained, flush the cooling system with clean water in order to remove any debris.
Close the coolant drain. Clean the drain plugs and install the 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 clean water. Install the filler cap. Operate the engine until the temperature reaches 49 °C (120 °F) to 66 °C (150 °F).
Stop the engine and allow the engine to cool. Ensure that the engine will not start when the cooling system is drained. Loosen the cooling system filler cap slowly in order to relieve any pressure. Remove the filler cap.
Open the coolant drain. Remove the drain plugs. Allow the coolant to drain. Flush the cooling system with clean water. Close the coolant drain. Install the drain plugs.
Repeat Steps 3, 4, and 5. Fill the Cooling System
Fill the cooling system no faster than 19 L (5 US gal) per minute to avoid air locks.
Fill the cooling system with Extended Life Coolant (ELC). After filling the cooling system, do not install the filler cap.
Start the engine. Operate the engine in order to purge the air from the cavities of the engine block. Allow the ELC to warm and allow the coolant level to stabilize. Stop the engine.
Check the coolant level. Maintain the coolant within 13 mm (.5 inch) below the bottom