Heater Core: Service and Repair

1. Remove A/C unit as follows:
a. Discharge refrigerant from A/C system as outlined in the Air Conditioning section.
b. Drain engine coolant into suitable container. It is not necessary to drain all coolant.
c. Disconnect water valve control cable from water valve, then the water hoses from heater core pipes.
d. Remove instrument panel and reinforcement as outlined in the Dash Panel Service section.
e. Remove blower unit as outlined under Blower Motor, Service and Repair.
f. Disconnect liquid and suction tube bolts, then the tubes from block joint. Cap openings to prevent contamination.
g. Remove rear air duct clips, then the air ducts.
h. Remove heater protector clips, then the protector, Fig. 1.

Fig. 33 Heater Protector Removal:

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i. Disconnect A/C unit electrical connectors from unit, then remove A/C unit nuts and A/C unit.
2. Remove heater core screws, then the clamps.
3. Disconnect heater pipes, then pull heater core out.
4. Reverse procedure to install, noting the following:
a. Lubricate new liquid and suction tube O-rings with compressor oil.
b. Torque liquid and suction tube bolts to 7 ft. lb.
c. Push water hose onto heater core pipe as far as ridge on pipe, then install hose clip.
d. Set temperature control switch to Cool position, then set water valve lever to Cool position and install control cable and lock clamp.
e. Charge system with refrigerant and inspect for leakage as outlined in the "Air Conditioning section.