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SMU - Revised Thermostat Replacement and Installation Procedures

Subject:Revised Thermostat Replacement and Installation Procedures

Models:1997-2001 Cadillac Catera
with 3.0 L V6 Engine (RPO L81)



This bulletin is being issued to revise the following procedures in the L81 3.0 L Engine Cooling sub-section of the appropriate Service Manual:

    • Thermostat Replacement
    • Thermostat Installation

The procedures are being revised to add sealant, P/N 12346004 (in Canada, use P/N 10953480), to the thermostat housing bolts before they are installed.

This information has been updated within SI2000. If you are using a paper version of this Service Manual, please mark a reference to this bulletin on the affected page.

Thermostat Replacement

Installation Procedure


    Object Number: 797528  Size: SH
  1. Install a new O-ring seal.
  2. Install the thermostat into the thermostat housing.

  3. Object Number: 797525  Size: SH
  4. Install the thermostat housing with the thermostat.
  5. Apply sealant, P/N 12346004 (in Canada, use P/N 10953480), to the thermostat housing bolt threads.
  6. Install the thermostat housing bolts.
  7. Tighten
    Tighten the thermostat housing bolts to 20 N·m (15 lb ft).


    Object Number: 142123  Size: SH
  8. Install the new O-rings on the coolant pipe.
  9. Lubricate the O-rings with coolant.

  10. Object Number: 142122  Size: SH
  11. Install the coolant pipe into the thermostat housing (2).
  12. Install the coolant pipe bolt (1).
  13. Tighten
    Tighten the thermostat coolant pipe bolt to 20 N·m (15 lb ft).


    Object Number: 142121  Size: SH
  14. Install the radiator inlet hose (1) to the thermostat outlet pipe.
  15. Install the radiator inlet hose clamp to the thermostat outlet pipe.
  16. Install the power steering reservoir and the power steering reservoir bracket.
  17. Install the power steering reservoir bracket bolt.
  18. Tighten
    Tighten the power steering reservoir bracket bolt to 7 N·m (62 lb in).

  19. Install the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical.
  20. Install the intake plenum. Refer to Intake Plenum Replacement in Engine Mechanical.
  21. Fill the cooling system. Refer to Draining and Filling Cooling System in Engine Cooling.

Thermostat Installation


    Object Number: 797528  Size: SH
  1. Install a new O-ring seal.
  2. Install the thermostat into the thermostat housing.

  3. Object Number: 797525  Size: SH
  4. Install the thermostat housing.
  5. Apply sealant, P/N 12346004 (in Canada, use P/N 10953480), to the thermostat housing bolts.
  6. Install the thermostat housing bolts.
  7. Tighten
    Tighten the thermostat housing bolts to 20 N·m (15 lb ft).


    Object Number: 142123  Size: SH
  8. Install the new O-rings on the coolant pipe.
  9. Apply coolant to the O-rings.

  10. Object Number: 769001  Size: SH
  11. Install the coolant pipe into the thermostat housing.