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For 1990-2009 cars only

Engine Coolant Thermostat Replacement RPO LSJ

Removal Procedure


    Object Number: 1649567  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Reposition the radiator surge tank outlet hose clamp (1) at the thermostat cover.
  3. Remove the radiator surge tank outlet hose from the thermostat cover.
  4. Reposition the oil cooler inlet and outlet hose clamps (1, 2) at the thermostat cover.
  5. Remove the oil cooler inlet and outlet hoses from the thermostat cover.

  6. Object Number: 1381548  Size: SH
  7. Remove the thermostat cover bolts and cover.
  8. Remove the thermostat.
  9. Remove and discard the thermostat cover O-ring seal.

Installation Procedure


    Object Number: 1381548  Size: SH
  1. Install a NEW thermostat cover O-ring seal into the recess groove.
  2. Install the thermostat, if necessary.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the thermostat cover bolts, if necessary.
  5. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1649567  Size: SH
  6. Install the oil cooler inlet and outlet hoses to the thermostat cover.
  7. Position the oil cooler inlet and outlet hose clamps (1, 2) at the thermostat cover.
  8. Install the radiator surge tank outlet hose to the thermostat cover.
  9. Position the radiator surge tank outlet hose clamp (1) at the thermostat cover.
  10. Fill the cooling system. Refer to Cooling System Draining and Filling .

Engine Coolant Thermostat Replacement RPO LE5

Removal Procedure


    Object Number: 1647551  Size: SH
  1. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
  2. Drain the cooling system. Refer to Cooling System Draining and Filling .
  3. If the vehicle is equipped with a engine oil cooler perform the following steps, otherwise proceed to step 8.
  4. Reposition the radiator outlet hose clamp (1) at the thermostat cover.
  5. Remove the radiator outlet hose from the thermostat cover.

  6. Object Number: 1647553  Size: SH
  7. Reposition the radiator surge tank outlet hose clamp (1) at the thermostat cover.
  8. Remove the radiator surge tank outlet hose from the thermostat cover.

  9. Object Number: 1649362  Size: SH
  10. If the vehicle is not equipped with a engine oil cooler perform the following steps, reposition the radiator outlet hose clamp (1) at the thermostat cover.
  11. Remove the radiator outlet hose from the thermostat cover.

  12. Object Number: 1713064  Size: SH
  13. Remove the thermostat cover bolts and cover.
  14. Remove the thermostat.
  15. Remove and discard the thermostat cover O-ring seal.

Installation Procedure


    Object Number: 1713064  Size: SH
  1. Install a NEW thermostat cover O-ring seal.
  2. Install the thermostat.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the thermostat cover bolts.
  5. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1649362  Size: SH
  6. If the vehicle is not equipped with a engine oil cooler perform the following steps, otherwise proceed to step 7.
  7. Install the radiator outlet hose to the thermostat cover.
  8. Reposition the radiator outlet hose clamp (1) at the thermostat cover. Proceed to step 11.

  9. Object Number: 1647553  Size: SH
  10. If the vehicle is equipped with a engine oil cooler perform the following steps, install the radiator surge tank outlet hose to the thermostat cover.
  11. Position the radiator surge tank outlet hose clamp at the thermostat cover.

  12. Object Number: 1647551  Size: SH
  13. Install the radiator outlet hose to the thermostat cover.
  14. Position the radiator outlet hose clamp (1) at the thermostat cover.
  15. Fill the cooling system. Refer to Cooling System Draining and Filling .
  16. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement .

Engine Coolant Thermostat Replacement L61

Removal Procedure


    Object Number: 1649362  Size: SH
  1. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
  2. Drain the cooling system. Refer to Cooling System Draining and Filling .
  3. Remove the radiator outlet hose (1) from the thermostat housing. Refer to Radiator Outlet Hose Replacement

  4. Object Number: 1713064  Size: SH
  5. Remove the thermostat cover bolts and cover.
  6. Remove the thermostat from the thermostat housing.
  7. Remove and discard the thermostat cover O-ring seal.

Installation Procedure


    Object Number: 1713064  Size: SH
  1. Install a NEW thermostat cover O-ring seal into the recess groove.
  2. Install the thermostat into the housing.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the thermostat cover bolts.
  5. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1649362  Size: SH
  6. Install the radiator outlet hose (1) to the thermostat housing.
  7. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement .
  8. Fill the cooling system to specifications. Refer to Cooling System Draining and Filling .