Engine Cooling System: Maintenance Cadillac STS I facelift

Draining Procedure

1. Park the vehicle on a level surface.
2. Remove the surge tank cap.
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-338130-S15906308302009081700000) .
4. Remove the air deflector. Refer to «Front Air Deflector Replacement»(ref-338114-S23457007412009081700000) .
5. Place a drain pan under the radiator.
6. Insert a piece of clean flexible hose through the access hole in the cradle onto the radiator mounting pin.
7. Slowly loosen the drain cock and drain the coolant into the drain pan. Do not completely remove the drain cock.
8. Inspect the engine coolant for the following conditions: Discolored appearance-Follow the flush procedure. Refer to «Flushing (Charge Air Cooling)»(ref-338194-S24395468232009081700000) or «Flushing (Powertrain)»(ref-338194-S19918342112009081700000) . Normal in appearance-Follow the Vac N Fill Procedure below.
9. Tighten the drain cock.

1. Park the vehicle on a level surface.
2. Remove the surge tank cap.
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-338130-S15906308302009081700000) .
4. Remove the air deflector. Refer to «Front Air Deflector Replacement»(ref-338114-S23457007412009081700000) .
5. Place a drain pan under the radiator.
6. Insert a piece of clean flexible hose through the access hole in the cradle onto the radiator mounting pin.
7. Slowly loosen the drain cock and drain the coolant into the drain pan. Do not completely remove the drain cock.
8. Inspect the engine coolant for the following conditions: Discolored appearance-Follow the flush procedure. Refer to «Flushing (Charge Air Cooling)»(ref-338194-S24395468232009081700000) «Flushing (Powertrain)»(ref-338194-S19918342112009081700000) . Normal in appearance-Follow the Fill Procedure below.

1. Remove the charge air cooling system pressure cap (1).
2. Remove the charge air coolant cap (2).
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-338130-S15906308302009081700000) .
4. Remove the front air deflector. Refer to «Front Air Deflector Replacement»(ref-338114-S23457007412009081700000) .
5. Place a drain pan under the charge air coolant radiator.
6. Remove the charge air coolant radiator drain plug.
7. Drain the charge air cooling system.
8. Inspect the coolant.
9. Follow the appropriate procedure based on the condition of the coolant. Normal in appearance - follow the filling procedure. Discolored - follow the flush procedure. Refer to «Flushing (Charge Air Cooling)»(ref-338194-S24395468232009081700000) or «Flushing (Powertrain)»(ref-338194-S19918342112009081700000) .
10. Install the charge air coolant radiator drain plug and tighten to 10 N.m (89 lb in).
11. Install the front air deflector. Refer to «Front Air Deflector Replacement»(ref-338114-S23457007412009081700000) .
12. Lower the vehicle.

1. Remove the charge air cooling system pressure cap (1).
2. Remove the charge air coolant cap (2).
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-338130-S15906308302009081700000) .
4. Remove the front air deflector. Refer to «Front Air Deflector Replacement»(ref-338114-S23457007412009081700000) .
5. Place a drain pan under the charge air coolant radiator.
6. Remove the charge air coolant radiator drain plug.
7. Drain the charge air cooling system.
8. Inspect the coolant.
9. Follow the appropriate procedure based on the condition of the coolant. Normal in appearance- follow the filling procedure. Discolored- follow the flush procedure. Refer to «Flushing (Charge Air Cooling)»(ref-338194-S24395468232009081700000) or «Flushing (Powertrain)»(ref-338194-S19918342112009081700000) .
10. Install the charge air coolant radiator drain plug and tighten to 10 N.m (89 lb in).
11. Install the front air deflector. Refer to «Front Air Deflector Replacement»(ref-338114-S23457007412009081700000) .
12. Lower the vehicle.

Vac - N - Procedure

1. Install the J 46143 onto the fill neck. See «Special Tools»(ref-338194-S08548216942009081700000) .
2. Attach the Vac-N-Fill cap to the J 46143 . See «Special Tools»(ref-338194-S08548216942009081700000) .
3. Attach the vacuum gage assembly to the Vac-N-Fill cap.
4. Attach the fill hose to the barb fitting on the vacuum gage assembly. Ensure the valve is closed.
5. Pour the coolant mixture into the graduated reservoir.
6. Install the vacuum tank on the graduated reservoir with the fill hose routed through the cut-out area in the vacuum tank.
7. Attach a shop air hose to the venturi assembly. Ensure the valve on the venturi assembly is closed.
8. Attach the vacuum hose to the vacuum gage assembly and the vacuum tank.
9. Open the valve on the venturi assembly. The vacuum gage will begin to rise and a hissing noise will be present.
10. Continue to draw vacuum until the needle stops rising. This should be 610-660 mm Hg (24-26 in Hg). Cooling hoses may start to collapse. This is normal due to vacuum draw.
11. To aid in the fill process, position the graduated reservoir above the fill neck.
12. Slowly open the valve on the vacuum gage assembly. When the coolant reaches the top of the fill hose, close the valve. This will eliminate air from the fill hose.
13. Close the valve on the venturi assembly.
14. If there is a suspected leak in the cooling system, allow the system to stabilize under vacuum and monitor for vacuum loss. If vacuum loss is observed, refer to «Loss of Coolant (LC3)»(ref-338194-S04917575742009081700000) or «Loss of Coolant (LH2, LY7, LLT)»(ref-338194-S31105212702009081700000) .
15. Open the valve on the vacuum gage assembly. The vacuum gage will drop as coolant is drawn into the system.
16. Once the vacuum reaches zero, close the valve on the vacuum gage assembly and repeat steps 11 and 17.
17. Detach the Vac-N-Fill cap from the J 46143 . See «Special Tools»(ref-338194-S08548216942009081700000) .
18. Remove the J 46143 from the fill neck. See «Special Tools»(ref-338194-S08548216942009081700000) .
19. Add coolant to the system as necessary.
20. Inspect the concentration of the coolant mixture using J 26568 . See «Special Tools»(ref-338194-S08548216942009081700000) .
21. Detach the vacuum hose from the vacuum gage assembly.
22. Attach the extraction hose to the vacuum hose.
23. Open the valve on the venturi assembly to start a vacuum draw.
24. Use the extraction hose to draw out the coolant to the proper level.
25. The vacuum tank has a drain valve on the bottom of the tank. Open the valve to drain coolant from the vacuum tank into a suitable container for disposal.
26. Install the charge air cooling system pressure cap.

Flushing (Charge Air Cooling)

Note. Do not use a chemical flush. Store used coolant in the proper manner, such as in a used engine coolant holding tank. Do not pour used coolant down a drain. Ethylene glycol antifreeze is a very toxic chemical. Do not dispose of coolant into the sewer system or ground water. This is illegal and ecologically unsound.

1. Follow the drain and fill procedure using only clean drinkable water. Repeat the procedure if necessary, until the fluid is nearly colorless. Refer to «Cooling System Draining and Filling (GE 47716)»(ref-338194-S38676017542009081700000) or «Cooling System Draining and Filling (Static Fill)»(ref-338194-S21329102432009081700000) .
2. Fill the cooling system to specifications when flushing is complete. Refer to «Cooling System Draining and Filling (GE 47716)»(ref-338194-S38676017542009081700000) or «Cooling System Draining and Filling (Static Fill)»(ref-338194-S21329102432009081700000) .

Flushing (Powertrain)

Note. Do not use a chemical flush. Store used coolant in the proper manner, such as in a used engine coolant holding tank. Do not pour used coolant down a drain. Ethylene glycol antifreeze is a very toxic chemical. Do not dispose of coolant into the sewer system or ground water. This is illegal and ecologically unsound. Various methods and equipment can be used to flush the cooling system. If special equipment is used, such as a back flusher, follow the manufacturer's instruction. However, always remove the thermostat before back flushing the system.

1. Block the drive wheels.
2. Place the transmission in PARK (P).
3. Engage the park brake.
4. Run the engine until the thermostat opens.
5. Stop the engine.
6. Follow the drain and fill procedure using only clean drinkable water. Repeat the procedure if necessary, until the fluid is nearly colorless. Refer to «Cooling System Draining and Filling (GE 47716)»(ref-338194-S38676017542009081700000) or «Cooling System Draining and Filling (Static Fill)»(ref-338194-S21329102432009081700000) .
7. Fill the cooling system when flushing is complete. Refer to «Cooling System Draining and Filling (GE 47716)»(ref-338194-S38676017542009081700000) or «Cooling System Draining and Filling (Static Fill)»(ref-338194-S21329102432009081700000) .