AC Condenser

This procedure covers the removal and replacement of the air conditioning condenser on a 1970 AMC Rebel Machine with 390ci V8 engine, including refrigerant recovery and system recharge.

Warnings

Tools required

Parts

• AC condenser × 1 — Use OEM specification or equivalent for 1970 AMC Rebel
• Condenser mounting hardware kit × 1 — May reuse if not corroded
• O-rings for refrigerant lines × 1 — R12 compatible
• Receiver/drier × 1 — Replace whenever system is opened
• Refrigerant oil × 1 — Mineral oil for R12 systems
• R12 refrigerant or approved substitute × 1 — Check local regulations

Preparation

1. Park vehicle on level surface and engage parking brake
2. Allow engine to cool completely if recently operated
3. Verify AC system refrigerant type (R12 original or conversion)
4. Connect AC recovery machine and fully recover refrigerant from system following EPA guidelines
5. Disconnect negative battery cable to prevent accidental fan operation

Procedure

1. 1

   Access condenser area
   Remove the grille assembly by removing the mounting bolts along the top and sides. On the Rebel Machine, there are typically 6-8 bolts securing the grille. Carefully pull the grille forward to access the condenser. You may need to disconnect any marker light wiring if present.
2. 2

   Disconnect refrigerant lines from condenser
   Using flare nut wrenches to prevent rounding, disconnect the liquid line from the bottom of the condenser and the discharge line from the top. These are typically flare fittings on 1970s AMC systems. Cap all open refrigerant line ends immediately to prevent moisture and contamination entry. Place drain pan underneath to catch any residual oil.
3. 3

   Remove condenser mounting bolts
   Locate and remove the condenser mounting brackets, typically secured with 4 bolts to the radiator support. The condenser on the Rebel Machine mounts in front of the radiator with rubber isolators at the mounting points. Note the position of any spacers or insulators for reinstallation.
4. 4

   Extract condenser
   Carefully lift the condenser up and out from between the radiator and grille opening. Be careful not to damage the radiator fins or condenser coils. The condenser may be tight in the available space; angle it as needed to clear the radiator support and surrounding components.
5. 5

   Inspect and prepare new condenser
   Inspect the new condenser for shipping damage. Check that mounting brackets transfer correctly from old unit if not included with new condenser. Add the appropriate amount of refrigerant oil to the new condenser as specified by the condenser manufacturer (typically 1-2 ounces for replacement). Use mineral oil for R12 systems.
6. 6

   Install new condenser
   Position the new condenser into the mounting location, ensuring rubber isolators are in place. Align with the radiator support brackets. Install mounting bolts finger-tight initially, then tighten evenly to secure the condenser. Ensure adequate clearance between condenser and radiator (typically 1/2 inch minimum).
7. 7

   Install new O-rings and reconnect refrigerant lines
   Install new O-rings on all refrigerant line fittings, lightly lubricating with refrigerant oil. Connect the discharge line to the top condenser fitting and liquid line to the bottom fitting. Hand-tighten flare nuts first, then snug with flare nut wrenches. Do not overtighten flare fittings as they seal on the cone seat, not thread torque.
8. 8

   Replace receiver/drier
   Locate the receiver/drier (typically mounted near the condenser or on the firewall). Disconnect refrigerant lines and remove mounting bracket. Install new receiver/drier with fresh O-rings, keeping caps on until final connection. Connect lines promptly to minimize moisture exposure.
9. 9

   Reinstall grille assembly
   Position the grille back onto the vehicle, reconnecting any marker light wiring. Install all grille mounting bolts and tighten securely. Verify grille alignment is correct and all mounting points are secure.
10. 10

    Evacuate AC system
    Connect vacuum pump to the AC system service ports. Evacuate the system to at least 29 inches of mercury vacuum for a minimum of 30-45 minutes. For systems that have been open to atmosphere, evacuate for 1 hour. Monitor vacuum gauge for vacuum hold after pump shutoff to verify no leaks.
11. 11

    Recharge AC system
    Using AC manifold gauges and refrigerant scale, charge the system with the correct type and amount of refrigerant. Original 1970 AMC Rebel AC systems typically held 2.5-3.0 pounds of R12. If system has been converted, follow conversion specifications. Charge through the low-side service port with engine running and AC on maximum.

Reassembly

1. Reconnect negative battery cable
2. Verify all refrigerant line connections are secure and properly tightened
3. Check for proper condenser to radiator clearance
4. Confirm grille assembly is properly aligned and secured

Verification

• Start engine and turn AC to maximum cold with blower on high
• Check for proper compressor engagement and cycling
• Use leak detector or soap solution to check all connection points for leaks
• Verify vent temperature reaches 40-50°F after 10-15 minutes of operation
• Monitor gauge pressures: low side should be 25-35 PSI, high side 200-250 PSI at 80°F ambient
• Check condenser for proper airflow and verify cooling fan operation
• Verify no unusual noises from AC system components

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