Primary (Front) Heater Core

Heater Distributor Case and Core Replacement

Remove or Disconnect

Figure 5 - Blower Motor Assembly - Component View:

Figure 6 - Heater Hose Routing - 4.3L, 5.0L, and 5.7L Engines:

Figure 7 - Heater Hose Routing - 6.2L Engine:

Figure 8 - Heater Inlet Hose Routing - 7.4L Engine:

Figure 9 - Distributor Ducts:

Figure 10 - Control Assembly and Cables:

1. Battery ground cable.
2. Coolant recovery tank.
3. Heater core hoses (140 and 141) (figures 6, 7, and 8).
- Place a clean pan under the vehicle to catch any coolant spillage.
- Plug the hoses.
- Allow coolant in the core to drain into the pan.
4. Heater distributor duct (134) (figure 9). Air Duct
- Remove the screws that hold the distributor duct to the distributor case and the distributor duct to the engine cover.
5. Engine housing cover.
- Refer to: Service and Repair
6. Instrument Panel.
7. Lower the steering column.
- Refer to: Service and Repair
- Raise and support the right side of the instrument panel.
8. Defroster duct (130) to distributor case (124) attaching screws.
9. Distributor to heater case screws.
10. Temperature door cable (145) (figure 10).
- Fold the cable back fro access.
11. Heater case (124) and core (122).
- Three nuts at the engine compartment side of the distributor case and one screw on the passenger side.
- Tilt the case assembly rearward at the top while lifting up until the core tubes clear the dash opening.
12. Core retaining straps (123).
13. Core (122.)

Install or Connect

Figure 5 - Blower Motor Assembly - Component View:

Figure 6 - Heater Hose Routing - 4.3L, 5.0L, and 5.7L Engines:

Figure 7 - Heater Hose Routing - 6.2L Engine:

Figure 8 - Heater Inlet Hose Routing - 7.4L Engine:

Figure 9 - Distributor Ducts:

Figure 10 - Control Assembly and Cables:

1. Core (122) to the heater case (124).
- Apply a bead of permagum sealer between the core and the case.
2. Core retaining straps (123).
3. Heater case (124) to the vehicle.
- Apply a bead of permagum sealer between the heater case and the opening in the vehicle.
- Tilt the case until the core tubes clear the cowl opening.
4. Temperature cable (145) to the heater case (124).
5. Distributor duct (134) to the heater case (124).
6. Defroster duct (130) to the heater case (124).
7. Instrument panel.
8. Steering column.
- Refer to: Service and Repair
9. Engine housing cover.
- Refer to: Service and Repair
10. Heater core hoses (140 and 141).
11. Coolant recovery tank.
12. New coolant to the radiator.
- Check for leaks.