GM Service Manual Online
For 1990-2009 cars only

Heater Inlet Hose Replacement LL8

Tools Required

    • J 43181 Heater Line Quick Connect Release Tool
    • GE-47622 Hose Clamp Pliers

Removal Procedure

  1. Drain the engine coolant. Refer to Cooling System Draining and Filling .

  2. Object Number: 744973  Size: SH
  3. Using the J 43181 , disconnect the inlet heater hose (2) from the heater core inlet tube.
  4. 2.1. Install the J 43181 to the quick connect on the outlet heater core hose (2).
    2.2. Close the tool around the inlet heater core hose.
    2.3. Firmly pull the tool into the quick connect end of the heater hose.
    2.4. Firmly grasp the heater hose (2). Pull the heater hose forward in order to disengage the hose from the heater core.
  5. Position the inlet heater hose clamp (1) at the engine block using GE-47622 .
  6. Remove the heater inlet hose (2) from the inlet hose fitting at the engine block.
  7. Remove the heater inlet hose.

Installation Procedure


    Object Number: 744973  Size: SH
  1. Apply coolant to the end of the heater inlet hose.
  2. Important: When installing a new heater inlet hose, place the clamps on the hose before installing the hose to the inlet hose fitting at the engine block.

  3. Install the heater inlet hose (2) to the inlet hose fitting at the engine block.
  4. Position the inlet heater hose clamp (1) at the engine block using GE-47622 .
  5. Install the quick connect end of the outlet heater core hose (2) to the heater core.
  6. Fill the engine cooling system. Refer to Cooling System Draining and Filling .

Heater Inlet Hose Replacement Auxiliary System

Tools Required

    • J 43181 Heater Line Quick Connect Release Tool
    • J 38185 Hose Clamp Pliers

Removal Procedure

  1. Drain the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement in Engine Cooling.

  3. Object Number: 735781  Size: SH
  4. Using the J 43181 disconnect the inlet heater hose (2) from the heater core inlet tube.
  5. 3.1. Install the J 43181 to the quick connect on the outlet heater core hose (2).
    3.2. Close the tool around the inlet heater core hose.
    3.3. Firmly pull the tool into the quick connect end of the heater hose.
    3.4. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.
  6. Reposition the hose clamp at the engine outlet using J 38185 .
  7. Remove the heater inlet hose (4) from the engine block.
  8. Remove the nut retaining the coolant bypass valve to the cowl.
  9. Remove the heater inlet hose.

Installation Procedure


    Object Number: 735781  Size: SH
  1. Apply coolant to the end of the heater inlet hoses.
  2. Important: When installing a new heater inlet hose, place the clamps on the hose before installing the hose to the inlet hose fitting at the engine block.

  3. Install the heater inlet hose to the inlet hose fitting at the engine block.
  4. Notice: Refer to Fastener Notice in the Preface section.

  5. Install the nut retaining the coolant bypass valve to the cowl.
  6. Tighten
    Tighten the nut to 10 N·m(89 lb in).

  7. Install the inlet heater hose to the engine block.
  8. Reposition the inlet heater hose clamp at the engine block using J 38185 .
  9. Install the quick connect end of the inlet heater core hose to the heater core.
  10. Install the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement in Engine Cooling.
  11. Fill the engine cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.