GM Service Manual Online
For 1990-2009 cars only

Heater Inlet Pipe Replacement RPO LNJ

Removal Procedure

  1. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling.

  3. Object Number: 1327499  Size: SH
  4. Release and slide the heater core inlet hose clamp away from the heater inlet pipe connection.
  5. Disconnect the heater core inlet hose from the heater inlet pipe.

  6. Object Number: 1087621  Size: SH
  7. Remove the heater inlet pipe nut (2).
  8. Remove the heater inlet pipe (1).
  9. Remove the seal (3) from the heater inlet pipe (1).

Installation Procedure

  1. Install a new seal (3) to the heater inlet pipe (1).
  2. Apply engine coolant to the heater inlet pipe seal (3).

  3. Object Number: 1087621  Size: SH
  4. Install the heater outlet pipe (1).
  5. Notice: Refer to Fastener Notice in the Preface section.

  6. Install the heater inlet pipe nut (2).
  7. Tighten
    Tighten the nut to 25 N·m (18 lb ft).


    Object Number: 1327499  Size: SH
  8. Connect the heater core inlet hose to the heater inlet pipe.
  9. Position the heater core inlet hose clamp over the heater inlet pipe connection.
  10. Fill the cooling system. Refer to Cooling System Draining and Filling.
  11. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement.

Heater Inlet Pipe Replacement RPO LY7

Removal Procedure


    Object Number: 1836897  Size: SH
  1. Partially drain the cooling system. Refer to Cooling System Draining and Filling.
  2. Remove the heater pipe inlet hose (1) from the heater inlet pipe.

  3. Object Number: 1836898  Size: SH
  4. Remove the heater inlet pipe housing bolts (1).
  5. Remove the housing.
  6. Remove the heater inlet pipe housing seal. Discard seal.

Installation Procedure


    Object Number: 1836898  Size: SH
  1. Install a NEW heater inlet pipe housing seal.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the heater inlet pipe housing bolts (1).
  4. Tighten
    Tighten the heater inlet housing bolts to 10 N·m (89 lb in).


    Object Number: 1836897  Size: SH
  5. Install the heater inlet hose (1) to the heater inlet pipe.
  6. Refill the cooling system. Refer to Cooling System Draining and Filling.