Cooling System Draining and Filling LL8

Warning: To avoid being burned, do not remove the radiator cap or surge tank cap while the engine is hot. The cooling system will release scalding fluid and steam under pressure if radiator cap or surge tank cap is removed while the engine and radiator are still hot.

Note: Draining the cooling system with the pressure cap installed will syphon the coolant from the overflow tank.

1. Park the vehicle on a level surface.
2. Allow the engine to cool.
3. Remove the radiator cap.
4. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
5. Place a drain pan under the lower radiator hose connection at the bottom of the radiator.
6. Using J 38185 slide the hose clamp back on the hose.
7. Slowly remove the outlet (lower) radiator hose and drain the coolant into the drain pan.
8. Inspect the engine coolant for the following conditions:

•	Discolored appearance--Follow the flush procedure. Refer to Flushing.

•	Normal in appearance--Follow the filling procedure.

•	If a complete block drain is required, remove the plug located on the LH side of the block.

Caution: The procedure below must be followed. Improper coolant level could result in a low or high coolant level condition, causing engine damage.

1. If a complete block drain was required, install the plug.
2. Install the outlet (lower) radiator hose.
3. Using J 38185 slide the clamp into the original position.
4. Lower the vehicle.

Note: Slowly add a mixture of 50/50 DEX-COOL antifreeze and deionized water to the cooling system through the top of the radiator until full. Refer to Approximate Fluid Capacities.

5. Remove coolant recovery reservoir cap.
6. Fill the coolant recovery reservoir with the remaining coolant.
7. Install coolant recovery reservoir cap.
8. Install the radiator cap.
9. Start the engine.
10. Run the engine at 1,000-3,000 RPM in 30 second intervals until the engine reaches normal operating temperature.
11. Allow the engine to idle for 3 minutes.
12. Shut the engine OFF.
13. Allow the engine to cool.
14. Top off the coolant recovery reservoir as necessary.
15. Rinse away any excess coolant from the engine and the engine compartment.
16. Inspect the cooling system for leaks.
17. Inspect the concentration of the engine coolant using J 26568 .

Cooling System Draining and Filling LH6, LS2

Special Tools

Warning: To avoid being burned, do not remove the radiator cap or surge tank cap while the engine is hot. The cooling system will release scalding fluid and steam under pressure if radiator cap or surge tank cap is removed while the engine and radiator are still hot.

Note: Draining the cooling system with the pressure cap installed will syphon the coolant from the overflow tank.

1. Park the vehicle on a level surface.
2. Allow the engine to cool.
3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
4. Place a drain pan under the lower radiator hose connection at the bottom of the radiator.
5. Using the pliers J 38185 , slide the hose clamp back on the hose.
6. Slowly remove the lower radiator hose and drain the coolant into the drain pan.
7. Inspect the engine coolant for the following conditions:

•	Discolored appearance--Follow the flush procedure. Refer to Flushing.

•	Normal in appearance--Follow the filling procedure.

•	If a complete block drain is required, remove the coolant heater or plug located on the LH side of the block. Refer to Coolant Heater Replacement.

8. Remove the radiator cap.

Caution: The procedure below must be followed. Improper coolant level could result in a low or high coolant level condition, causing engine damage.

1. If a complete block drain was required, install the coolant heater or plug. Refer to Coolant Heater Replacement.
2. Install the lower radiator hose.
3. Using the pliers J 38185 , slide the clamp into the original position.
4. Lower the vehicle.

Note: Slowly add a mixture of 50/50 DEX-COOL antifreeze and deionized water to the cooling system through the top of the radiator until full. Refer to Approximate Fluid Capacities.

5. Install the radiator cap.
6. Remove coolant recovery reservoir cap.
7. Slowly add a mixture of 50/50 DEX-COOL antifreeze and deionized water to the cooling system through the coolant recovery reservoir. Refer to Approximate Fluid Capacities.
8. Fill the coolant recovery reservoir with the remaining coolant.
9. Install the coolant recovery reservoir cap.
10. Start the engine.
11. Run the engine from 1,000-3,000 RPM in 30-second intervals until the engine reaches normal operating temperature.
12. Allow the engine to idle for 3 minutes before repeating the last step.
13. Shut the engine OFF.
14. Allow the engine to cool.
15. Top off the coolant recovery reservoir as necessary.
16. Rinse away any excess coolant from the engine and the engine compartment.
17. Inspect the cooling system for leaks.
18. Inspect the concentration of the engine coolant using the fluid tester J 26568 .