GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2008 🢒 Astra 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Engine Coolant Thermostat Replacement

Removal Procedure

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

  1. Open the hood.
  2. Disconnect the battery.
    3. • Remove the negative connection from the ground terminal.
    • Loosen the nut.
  3. Raise the vehicle by its full height.
  4. Place a drain pan underneath.

    5. Object Number: 1936581 Size: SH
  5. Drain the coolant.
    6. • Place a drain pan underneath.
    • Install the suitable hose to the drain connection (2).
    • Open the coolant drain screw (1).
    • Drain the coolant.
    • Close the coolant drain screw.

    Object Number: 1945801 Size: SH
  6. Lower the vehicle by its full height.
  7. Remove the wiring harness bracket (1) from the thermostat housing.

    8. Remove the nut (2).

  8. Disconnect the thermostat wiring harness plug (4).
  9. Remove the upper radiator hose (5) from the coolant discharge port.

    10. Release the clamp.

  10. Remove the thermostat housing (3).

    11. Remove the 4 bolts.

Installation Procedure
  1. Clean the sealing surface.

    2. Notice: Refer to Fastener Notice in the Preface section.

  2. Install the thermostat.

    3. Replace the gasket.

    Tighten
    Tighten the 4 bolts to 8 N·m (70 lb in).

  3. Install the upper radiator hose to the coolant discharge port.

    4. Fasten the clamp.

  4. Install the wiring harness bracket to the thermostat housing.

    5. Tighten
    Tighten the nut to 5 N·m (44 lb in).

  5. Connect the thermostat wiring harness plug.
  6. Fill and bleed the cooling system. Refer to Cooling System Draining and Filling .
  7. Connect the battery.

    8. Install the negative connection to the ground terminal.

    Tighten
    Tighten the nut to 5 N·m (44 lb in).

  8. For reprogramming procedures, refer to Control Module References .
  9. Close the hood.