Kohler 20-3250 kW manual Cooling System Component Inspection, Procedure to Drain Cooling System

3.7.2Cooling System Component Inspection

To prevent generator set shutdown or damage caused by overheating:

DKeep the cooling air inlets clean and unobstructed.

DInspect the radiator’s exterior for obstructions. Remove dirt and foreign material using a soft brush or cloth to avoid damaging the radiator fins.

DCheck the hoses and connections for leaks. Replace any cracked, frayed, or spongy hoses.

DCheck the condition and tension of the radiator fan and water pump belt(s). Follow the belt tension procedure in this manual and/or the engine operation manual.

DCheck the pressure cap seal and replace a cracked or deteriorated cap. Remove dirt and other debris from the pressure cap and filler neck. The pressure cap raises the boiling point of the coolant, enabling higher operating temperatures. Replace a leaking pressure cap with one rated for the same pressure. The pressure cap rating usually appears on the pressure cap.

3.7.3Procedure to Drain Cooling System

For optimum protection, drain, flush, and refill the cooling system at the intervals listed in the service schedule.

Note: Dispose of all waste materials (oil, fuel, coolant, filters, and gaskets) in an environmentally safe manner.

1.Deenergize the block heater, if equipped.

2.Remove the pressure cap to allow the entire system to drain and prevent air pockets from restricting coolant flow through the engine block.

3.Open the radiator and/or engine block coolant drain valve(s) and allow the system to drain.

4.If the inside of the radiator has mineral deposits or the used coolant contains dirt or grease, refer to Section 3.7.4, Procedure to Flush and Clean the Cooling System. If the cooling system does not have mineral deposits, go to Section 3.7.5, Procedure to Refill the Cooling System.

3.7.4Procedure to Flush and Clean Cooling System

Use the instructions in the engine operation manual when available to flush and clean the cooling system. Otherwise, use the following procedure and the cooling system cleaner manufacturer’s instructions.

1.Flush the cooling system with clean water.

2.If the inside of the radiator still has mineral deposits, use a radiator cleaner to remove the remaining deposits following the manufacturer’s instructions.

3.Drain, clean, and flush the coolant recovery tank.

3.7.5Procedure to Refill Cooling System

See the generator set spec sheet for coolant capacity.

Note: Do not add coolant to a hot engine. Adding coolant to a hot engine can cause the cylinder block or cylinder head to crack. Wait until the engine has cooled.

1.Remove the pressure cap.

2.Close the radiator and/or engine block coolant drain valve(s) and tighten the cooling system hose clamps.

3.Open the air-bleed petcocks, if equipped. Close the air-bleed petcocks when coolant begins to flow from them.

4.Add coolant additives or water pump lubricants according to the engine manufacturer’s recommendations in the engine operation manual.

5.Fill the cooling system with the recommended coolant/antifreeze mixture of 50% ethylene glycol and 50% clean, softened water to inhibit rust/corrosion and prevent freezing.

Note: A coolant solution of 50% ethylene glycol provides freezing protection to --37°C (--34°F) and overheating protection to 129°C (265°F). A coolant solution containing less than 50% ethylene glycol may not provide adequate freezing and overheating protection. A coolant solution containing more than 50% ethylene glycol can cause engine or component damage. Do not use alcohol or methanol antifreeze or mix them with the specified coolant. Refer to the engine operation manual for recommendations regarding the coolant mixture to use in extreme temperatures.

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