Heater Core: Service and Repair

Remove or Disconnect

1. Hose pipe clamp bolt/screw and hose pipe clamp.
^ Clamp off heater hoses.

NOTICE: Heater core can be damaged if too much force is applied to heater core pipes during hose removal.

2. Heater hose from heater core pipes.
3. Open instrument panel compartment. Push in on sides of compartment to release it to reach heater core.
4. Heater module bolts/screws.
5. Heater module cover.
6. Heater core bolt/screw and heater core clamp.
7. Heater core.
^ Carefully pull heater core toward you.

Install or Connect

1. Heater core.

Important
^ Lubricate Heater pipes for good seal.
^ Be sure seals around heater pipes remain in place when installing.
^ To verify that seal is installed correctly, observe seal from inside engine compartment. If seal leaks, apply sealer GM P/N 3012078 between heater core pipes and evaporator housing.

2. Heater core bolt/screw and heater core clamp.

Tighten
^ Heater core bolt/screw to 1.8 Nm (16 lb in).

3. Hose pipe clamp bolt/screw and hose pipe clamp.
^ Unclamp heater hoses.

Tighten
^ Hose pipe clamp bolt/screw to 1.8 Nm (16 lb in).

4. Heater hose to heater core pipes.
5. Heater module cover.
6. Heater module bolts/screws.

Tighten
^ Heater module bolts/screws to 2 Nm (18 lb in).

7. Engine coolant.
^ Use coolant drained earlier only if it is uncontaminated. Discard contaminated coolant and add 50/50 mixture of water (preferably distilled) and GM Goodwrench DEX-COOL or Havoline DEX-COOL (orange-colored, silicate free) antifreeze conforming to GM Specification 6277M.
8. Instrument panel compartment.