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For 1990-2009 cars only

Heater Inlet Hose Replacement Utility L18

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the air intake tube.
  3. Remove the heater and surge tank hoses from the mounting clip.

  4. Object Number: 12777  Size: SH
  5. Squeeze the plastic retainer release tabs.

  6. Object Number: 12778  Size: SH
  7. Pull the connection apart.

  8. Object Number: 651354  Size: SH
  9. Remove the inlet heater hose (1) from the coolant outlet fitting.
  10. Remove the inlet heater hose.

Installation Procedure

  1. Install the inlet heater hose.

  2. Object Number: 651354  Size: SH
  3. Install the inlet heater hose (1) to the coolant outlet fitting.

  4. Object Number: 21855  Size: SH
  5. Connect the heater and surge tank hoses to the heater core.
  6. Important: Firmly push the quick connect onto the heater core pipe until you hear an audible click.

  7. Install the heater and surge tank hoses to the mounting clip.
  8. Install the air intake tube.
  9. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

Heater Inlet Hose Replacement Utility LR4, LM7, LQ4

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the air intake tube.
  3. Remove the heater and surge tank hoses from the mounting clip.

  4. Object Number: 12777  Size: SH
  5. Squeeze the plastic retainer release tabs.

  6. Object Number: 12778  Size: SH
  7. Pull the connection apart.

  8. Object Number: 363237  Size: SH
  9. Remove the inlet heater hose from the water pump.

  10. Object Number: 363118  Size: SH
  11. Remove the inlet heater hose.

Installation Procedure


    Object Number: 363118  Size: SH
  1. Install the inlet heater hose.

  2. Object Number: 363237  Size: SH
  3. Install the inlet heater hose to the water pump.

  4. Object Number: 21855  Size: SH
  5. Connect the heater hose to the heater core.
  6. Important: Firmly push the quick connect onto the heater core pipe until you hear an audible click.

  7. Install the heater and surge tank hoses to the mounting clip.
  8. Install the air intake tube.
  9. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

Heater Inlet Hose Replacement Avalanche/XLT L18

Tools Required

J 43181 Quick Connect Connector Removal Tool

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the air intake tube.
  3. Remove the heater and surge tank hose from the mounting clip.

  4. Object Number: 362171  Size: SH
  5. Using the J 43181 disconnect the heater hose from the heater core inlet.
  6. 4.1. Install the J 43181 to the heater core pipe.
    4.2. Close the tool around the heater core pipe.
    4.3. Firmly pull the tool into the quick connect end of the heater hose.
    4.4. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.

    Object Number: 651354  Size: SH
  7. Remove the inlet heater hose (1) from the engine coolant inlet fitting.
  8. Remove the inlet heater hose.

Installation Procedure

  1. Install the inlet heater hose.

  2. Object Number: 651354  Size: SH
  3. Install the inlet heater hose (1) to the engine coolant inlet fitting.

  4. Object Number: 362171  Size: SH
  5. Connect the heater and surge tank hose to the heater core.
  6. Firmly push the quick connect onto the heater core pipe until you hear an audible click.

  7. Install the heater and surge tank hose to the mounting clip.
  8. Install the air intake tube.
  9. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.

Heater Inlet Hose Replacement Avalanche/XLT LR4, LM7, LQ4

Tools Required

J 43181 Quick Connect Connector Removal Tool

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the air intake tube.
  3. Remove the heater and surge tank hose from the mounting clip.

  4. Object Number: 362171  Size: SH
  5. Using the J 43181 disconnect the heater hose from the heater core inlet.
  6. 4.1. Install the J 43181 to the heater core pipe.
    4.2. Close the tool around the heater core pipe.
    4.3. Firmly pull the tool into the quick connect end of the heater hose.
    4.4. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.

    Object Number: 363237  Size: SH
  7. Remove the inlet heater hose from the engine.

  8. Object Number: 363118  Size: SH
  9. Remove the inlet heater hose.

Installation Procedure


    Object Number: 363118  Size: SH
  1. Install the inlet heater hose.

  2. Object Number: 363237  Size: SH
  3. Install the inlet heater hose to the engine.
  4. Connect the heater and surge tank hose to the heater core.
  5. Firmly push the quick connect onto the heater core pipe until you hear an audible click.

  6. Install the heater and surge tank hose to the mounting clip.
  7. Install the air intake tube.
  8. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.