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For 1990-2009 cars only

Engine Coolant Thermostat Housing Replacement 3.6L Engine SWB

Removal Procedure

    Caution: Refer to Battery Disconnect Caution in the Preface section.

  1. Disconnect the battery ground cable from the battery. Refer to Battery Negative Cable Disconnection and Connection.
  2. Remove the engine cover. Refer to Engine Cover Replacement.
  3. Remove the air intake duct. Refer to Air Cleaner Inlet Duct Replacement.
  4. Remove the radiator air baffle and deflector. Refer to Radiator Air Upper Baffle and Deflector Replacement.
  5. Remove the catalytic converter assembly from the vehicle. Refer to Catalytic Converter Replacement - Right Side.
  6. Lower the transmission by 65mm. Refer to Transmission Replacement.
  7. Important: Store used coolant in the correct 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.

  8. Drain the cooling system. Refer to Cooling System Draining and Filling.
  9. Important: Do NOT separate the upper and lower intake manifolds.

  10. Remove the intake manifolds. Refer to Lower Intake Manifold Replacement.
  11. Important: Assure material used to cover intake ports is lint free to prevent any foreign matter entering the ports.

  12. Cover the exposed intake ports.
  13. Remove the coolant inlet pipe. Refer to Engine Coolant Inlet Pipe Replacement.
  14. Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1957882  Size: SH
  15. Detach the heater hose (1) quick connect fitting by releasing the retaining clip (3) with a suitable screwdriver, from the heater pipe (2).
  16. Disconnect the heater hoses (1) from the heater pipes (2).
  17. Disconnect the engine harness to obtain easier access to the heater hose flange and thermostat housing bolts. Refer to Ignition Coil Replacement - Bank 1 and Ignition Coil Replacement - Bank 2.

  18. Object Number: 1957884  Size: SH
  19. Remove the heater hose assembly to right hand cylinder head retaining bolt (3).
  20. Remove the heater hose assembly to thermostat housing retaining bolts (5).
  21. Remove the heater hose assembly (4) from the thermostat housing (1) and cylinder head (2).
  22. Remove the O-ring seals (6)
  23. Discard the O-ring seals


    Object Number: 1957887  Size: SH

    Important: The thermostat housing has one longer bolt which is located in the upper left of the housing.

    Important: When replacing the thermostat housing always renew the block gasket (1).

  24. Remove the thermostat housing retaining bolts (4) rubber grommets (3) then remove the thermostat housing (2).

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1957887  Size: SH
  1. Install the thermostat housing retaining bolts (4) ensuring a new block gasket (1) and rubber grommets (3) has been fitted.
  2. Tighten
    Tighten the bolts (4) to 10  N·m (89 lb in).


    Object Number: 1957884  Size: SH
  3. Install the NEW O-ring seals (6) to the thermostat housing (1).
  4. Install the heater pipe assembly (4) to the thermostat housing (1) and cylinder head (2).
  5. Notice: Refer to Fastener Notice in the Preface section.

  6. Install the heater hose assembly to thermostat housing retaining bolts (5).
  7. Tighten
    Tighten the bolts to 10  N·m (89 lb in).

  8. Install the heater hose assembly to right hand cylinder head retaining bolt (3)
  9. Tighten
    Tighten the bolt to 35  N·m (26 lb ft).

  10. Install the engine harness. Refer to Ignition Coil Replacement - Bank 1 and Ignition Coil Replacement - Bank 2.
  11. Caution: Refer to Installing Hoses without Twists or Bends Notice in the Preface section.

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1957902  Size: SH
  12. Attach the heater hose (1) quick connect fitting (3) by pushing the hose onto the heater pipe (2) listen for a audible click to confirm fitting.
  13. Install the coolant inlet pipe. Refer to Engine Coolant Inlet Pipe Replacement.
  14. Important: Do NOT separate the upper and lower intake manifolds.

  15. Install the intake manifolds. Refer to Upper Intake Manifold Replacement and Refer to Lower Intake Manifold Replacement.
  16. Install the air deflector. Refer to Front Air Deflector Replacement.
  17. Install the air intake duct. Refer to Air Cleaner Inlet Duct Replacement.
  18. Install the engine cover. Refer to Engine Cover Replacement.
  19. Install the radiator air baffle and deflector. Refer to Radiator Air Upper Baffle and Deflector Replacement.
  20. Connect the battery ground cable to the battery. Refer to Battery Negative Cable Disconnection and Connection.
  21. Fill the cooling system. Refer to Cooling System Draining and Filling.
  22. Inspect cooling system for leaks.

Engine Coolant Thermostat Housing Replacement 3.6L Engine LWB

Removal Procedure

    Caution: Refer to Battery Disconnect Caution in the Preface section.

  1. Disconnect the battery ground cable from the battery. Refer to Battery Negative Cable Disconnection and Connection.
  2. Remove the engine cover. Refer to Engine Cover Replacement in Engine Mechanical - 3.6L.
  3. Remove the air intake duct. Refer to Air Cleaner Inlet Duct Replacement.
  4. Remove the radiator air baffle and deflector. Refer to Radiator Air Upper Baffle and Deflector Replacement in Body Front End.
  5. Remove the catalytic converter assembly from the vehicle. Refer to Catalytic Converter Replacement - Right Side.
  6. Lower the transmission by 65mm. Refer to Transmission Replacement.
  7. Important: Store used coolant in the correct 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.

  8. Drain the cooling system. Refer to Cooling System Draining and Filling.
  9. Important: Do NOT separate the upper and lower intake manifolds.

  10. Remove the intake manifolds. Refer to Upper Intake Manifold Replacement and Refer to Lower Intake Manifold Replacement.
  11. Important: Assure material used to cover intake ports is lint free to prevent any foreign matter entering the ports.

  12. Cover the exposed intake ports.
  13. Remove the coolant inlet pipe. Refer to Engine Coolant Inlet Pipe Replacement in Engine Cooling.
  14. Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1957882  Size: SH
  15. Detach the heater hose (1) quick connect fitting by releasing the retaining clip (3) with a suitable screwdriver, from the heater pipe (2).
  16. Disconnect the heater hoses (1) from the heater pipes (1).
  17. Disconnect the engine harness to obtain easier access to the heater hose flange and thermostat housing bolts. Refer to Ignition Coil Replacement - Bank 1 and Ignition Coil Replacement - Bank 2.

  18. Object Number: 1957884  Size: SH
  19. Remove the bolt (3) which secures the heater hose assembly (4) to the right hand cylinder head (2).
  20. Remove the heater hose assembly to thermostat housing (1) retaining bolts (5).
  21. Remove the heater hose assembly and discard the O-ring seals (6).

  22. Object Number: 1957887  Size: SH

    Important: The thermostat housing has one longer bolt which is located in the upper left of the housing.

    Important: When replacing the thermostat housing always renew the block gasket (1).

  23. Remove the thermostat housing retaining bolts (4) rubber grommets (3) then remove the thermostat housing (2).

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1957887  Size: SH
  1. Install the thermostat housing retaining bolts (4) ensuring a new block gasket (1) and rubber grommets (3) has been fitted.
  2. Tighten
    Tighten the bolts (4) to 10  N·m (89 lb in).

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1957884  Size: SH
  3. Install the heater pipe assembly (4) to thermostat housing (1) retaining bolts ensuring new O-ring seals (6) have been fitted.
  4. Tighten
    Tighten the bolts (5) to 10  N·m (89 lb in).

  5. Install the heater pipe assembly (4) to cylinder head (2) retaining bolt (3).
  6. Tighten
    Tighten the bolts to 35  N·m (26 lb ft).

  7. Install the engine harness. Refer to Ignition Coil Replacement - Bank 1 and Ignition Coil Replacement - Bank 2.
  8. Caution: Refer to Installing Hoses without Twists or Bends Notice in the Preface section.

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1957902  Size: SH
  9. Attach the heater hose (1) quick connect fitting (3) by pushing the hose onto the heater pipe (2) listen for a audible click to confirm fitting.
  10. Install the coolant inlet pipe. Refer to Engine Coolant Inlet Pipe Replacement in Engine Cooling.
  11. Important: Do NOT separate the upper and lower intake manifolds.

  12. Install the intake manifolds. Refer to Upper Intake Manifold Replacement and Refer to Lower Intake Manifold Replacement.
  13. Install the air deflector. Refer to Front Air Deflector Replacement.
  14. Install the air intake duct. Refer to Air Cleaner Inlet Duct Replacement.
  15. Install the engine cover. Refer to Engine Cover Replacement in Engine Mechanical - 3.6L.
  16. Install the radiator air baffle and deflector. Refer to Radiator Air Upper Baffle and Deflector Replacement in Body Front End.
  17. Connect the battery ground cable to the battery. Refer to Battery Negative Cable Disconnection and Connection.
  18. Fill the cooling system. Refer to Cooling System Draining and Filling.
  19. Inspect cooling system for leaks.

Engine Coolant Thermostat Housing Replacement 6.0L Engine

Removal Procedure

    Caution: Refer to Battery Disconnect Caution in the Preface section.

    Important: Refer to Battery Negative Cable Disconnection and Connection.

  1. Disconnect the battery ground cable from the battery.
  2. Caution: Refer to Radiator Cap Removal Caution in the Preface section.

  3. Ensure engine is below 50 C before removing the coolant pressure cap.
  4. Remove the radiator air baffle and deflector. Refer to Radiator Air Upper Baffle and Deflector Replacement
  5. Remove the air intake duct. Refer to Air Cleaner Inlet Duct Replacement
  6. Caution: Refer to Safety Glasses Caution in the Preface section.

    Caution: Refer to Vehicle Lifting Caution in the Preface section.

  7. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  8. Drain the coolant into a suitable container. Refer to Cooling System Draining and Filling.
  9. Lower the vehicle.
  10. Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1949738  Size: SH
  11. Release the retaining hose clamp (2) and detach the hose (3) from the thermostat housing end (1).

  12. Object Number: 1949739  Size: SH
  13. Remove the thermostat housing (2) to water pump retaining bolts (1), and remove thermostat housing.
  14. If the housing is to be replaced, discard the O-ring.

Installation Procedure

  1. Install thermostat. Refer to Engine Coolant Thermostat Replacement.
  2. Ensure all mating surfaces are thoroughly cleaned, using only a fine abrasive material.

  3. Object Number: 1949739  Size: SH

    Important: Ensure a new O-ring seal is used.

  4. Install the thermostat housing (2).
  5. Install the thermostat housing to water Pump retaining bolts (1).
  6. Notice: Refer to Fastener Notice in the Preface section.

    Tighten
    Tighten the bolts (1) to 14  N·m (124 lb in).

    Caution: Refer to Installing Hoses without Twists or Bends Notice in the Preface section.

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1949738  Size: SH
  7. Install the hose (3) to the thermostat housing (1), by opening the retaining hose clamp (2) and securing it over the hose.
  8. Install the radiator air baffle and deflector. Refer to Radiator Air Upper Baffle and Deflector Replacement
  9. Install the air intake duct. Refer to Air Cleaner Inlet Duct Replacement
  10. Fill the cooling system. Refer to Cooling System Draining and Filling.
  11. Connect the battery ground cable to the battery. Refer to Battery Negative Cable Disconnection and Connection.
  12. Inspect cooling system for leaks.