Heater Core: Service and Repair

Less Air Conditioning
1. Disconnect battery ground cable.
2. Remove I/P as described under ``Instrument Panel, Replace''
3. Drain coolant from radiator, then disconnect heater hoses from heater core. Plug core tubes or blow residual coolant from core using low pressure air.
4. Disconnect vacuum supply hose from in-line check valve in engine compartment.
5. Remove I/P shake brace attaching screw and the brace from heater brace.
6. Remove floor register or rear seat adapter from bottom of heater case.
7. Remove three heater case-to-dash panel attaching screws from engine compartment.
8. Remove two bracket-to-cowl top panel attaching screws.
9. Carefully remove heater case from vehicle.
10. Remove vacuum source line from heater core tube seal.
11. Remove seal from heater core tubes.

Fig. 29 Heater core removal:

12. Remove heater core cover attaching screws and the cover, Fig. 29.
13. Remove heater core and seals from heater case.
14. Reverse procedure to install.

With Air Conditioning
1. Remove evaporator case as described under ``Evaporator Case, Replace.''
2. Remove vacuum source line from heater core tube seal.
3. Remove seal from heater core tubes.
4. On models with Automatic Electronic Temperature Control, remove blend door actuator attaching screws and the actuator from evaporator case.
5. On all models, remove heater core cover attaching screws, then the cover and seal.
6. Remove heater core and seals from evaporator case.