Heater Core: Service and Repair

Heater Core

Fig. 6 Exploded view of heater system. 1984:

1. Disconnect battery ground cable.
2. Drain coolant from radiator using drain plug.
3. Disconnect both heater inlet and outlet hoses from the heater unit, Fig. 6.
4. Using a suitable screwdriver, remove the heater hose grommet from the inside firewall.
5. Remove the six radio housing or console retaining screws and the unit with which the model is equipped.
6. Remove the instrument panel and package tray.
7. Remove the large duct between the blower assembly and the heater unit.
8. Remove the left and right defroster nozzles.
9. Remove the two upper heater unit retaining bolts.
10. Lift the heater unit up approximately .39 inches and remove from installed position.
11. Remove the heater core fitting assembly cover.
12. Disconnect the rod from the plastic clamp.
13. Remove both the inlet and outlet hose clamps. Twist the cotter pin counterclockwise to remove the outlet hose clamp.
14. To remove the heater core fitting assembly, remove the retaining screws and pull the assembly up and forward.
15. Disconnect the defroster flap control rod.
16. Remove the twelve heater case retaining clips and separate the halves.
17. Remove the heater core.
18. Reverse procedure to install.