3100 SERIES INDUSTRIAL ENGINES Cooling System Caterpillar

Cooling System
1.1. Engine Jacket Water
2.2. Checking Coolant Level
3.2. Draining Radiator
4.2. Draining Complete Cooling System
5.2. Flushing Cooling System
6.2. Filling Cooling System

Engine Jacket Water

Checking Coolant Level

With the engine warm and stopped:

1. Slowly loosen the filler cap and release pressure.

------ WARNING! ------

Be careful; steam may spray. Avoid being burned.

2. Push downward and turn the cap until it is released.
3. Maintain coolant level to within 1/2 inch (1 cm) below bottom of fill pipe. The coolant will expand as it is heated.
4. Make-up coolant must be one of the following:
a. Permanent anti-freeze and water solution.
b. Drinkable water and rust inhibitor solution.

For emergencies, and only as a "temporary fix" until the cooling system can be returned to either (a) or (b), use either:

c. Drinkable water.
d. Any available water.

"Drinkable water" is clean water that is low in scale forming minerals - not softened water. Never add coolant to an overheated engine; allow it to cool first.

Check specific gravity of anti-freeze solution frequently in cold weather to assure adequate protection.

Draining Radiator

Whenever it is necessary to drain the cooling system for repairs:

1. Remove the filler cap.
2. Open the drain valve for the radiator.

Draining Complete Cooling System

1. Drain the radiator; see the topics above.
2. Remove the thermostat housing drain plug.
3. Remove both engine block drain plugs.
4. Remove the coolant; then install all drain plugs.

Flushing Cooling System

To clean the cooling system, any good commercial radiator cleaning solution can be used. Follow the instructions included with the cleaner.

The cooling system can be cleaned using oxalic acid and sodium carbonate as follows:

1. Fill the cooling system with a solution consisting of one pound of oxalic acid or sodium bisulphate (NaHSO4) with every 5 gallons of water (mix 0,24 kg. with every 10 liters of water).
2. Start the engine and operate at operating temperatures for 1/2 to 1 hour.
3. Stop the engine and drain the cooling system.
4. Flush the system with clean water until the draining water is clear.
5. Install all drain plugs.
6. Fill with a solution consisting of 1/2 pound of sodium carbonate crystals (Na2CO3, 10H2O) with every 10 gallons of water (mix 0,06 kg with every 10 liters of water).
7. Start and run the engine for 10 minutes.
8. Stop the engine and drain the cooling system.
9. Flush the cooling system with clean water.
10. Install all drain plugs.

Filling Cooling System

1. Add anti-freeze, if required.
2. Fill to correct level with water which is free as possible from scale forming minerals.
3. Start and run engine for 10 minutes.
4. Remove the radiator cap and check the coolant level.
5. Add coolant, if needed, until coolant level is to the bottom of the filler tube.
6. Install the radiator cap.