Air Conditioning Compressor Replacement LG5

Tools Required

J 39400-A Halogen Leak Detector

1. Remove the right wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.
2. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging .
3. Remove the air cleaner layer. Refer to Caterpillar® 3126 Unit Repair Manual.
4. Remove the drive belt. Refer to Caterpillar® 3126 Unit Repair Manual.
5. Disconnect the compressor clutch electrical connector.
6. Disconnect the high pressure switch connector.



7. Remove the compressor hose bolt (1) from the compressor (3).

Important: When removing the sealing washers, prevent dirt and foreign material from getting onto the following sealing surfaces:

•	The washers

•	The hose fitting

•	The compressor ports

Use a lint-free cloth in order to clean all of the sealing surfaces.
8. Remove the compressor sealing washers.

Discard the compressor sealing washers.

9. Remove the refrigerant hoses from the compressor.



10. Remove the compressor mounting bolts (1).
11. Remove the compressor (2).
12. If replacing the compressor, balance the refrigerant oil. Refer to Compressor Oil Balancing .

1. Install the compressor (2).

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.




2. Install the compressor mounting bolts (1).

Tighten
Tighten the bolts to 50 N·m (37 lb ft).

3. Install the new compressor sealing washers. Refer to Sealing Washer Replacement .



4. Install the refrigerant hose fitting (2) to the compressor (3).
5. Install the compressor hose bolt.

Tighten
Tighten the bolt to 35 N·m (26 lb ft).

6. Connect the compressor clutch electrical connector.
7. Connect the high pressure switch connector.
8. Install the drive belt. Refer to Caterpillar® 3126 Unit Repair Manual.
9. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
10. Leak test the fittings of the component using the J 39400-A .
11. Install the air cleaner layer. Refer to Caterpillar® 3126 Unit Repair Manual.
12. Install the right wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.

Air Conditioning Compressor Replacement L18

Tools Required

J 39400-A Halogen Leak Detector

1. Remove the right wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.
2. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging .
3. Remove the air cleaner layer. Refer to Air Cleaner Replacement in Engine Controls-8.1L.
4. Remove the drive belt. Refer to Drive Belt Replacement in Engine Mechanical-8.1L.
5. Disconnect the compressor clutch electrical connector.
6. Disconnect the high pressure switch electrical connector.




Important: When removing the sealing washers, prevent dirt and foreign material from getting on the following sealing surfaces:

•	The washers

•	The hose fitting

•	The compressor sealing surface

Use a lint-free cloth in order to clean all of the sealing surfaces.
7. Remove the compressor hose bolt (1).
8. Disconnect the compressor hose.
9. Remove the compressor sealing washers and discard.
10. Remove the refrigerant hoses (2) from the compressor (3).



11. Remove the compressor mounting bolts (1).
12. Remove the compressor (2).
13. If replacing the compressor, balance the refrigerant oil. Refer to Compressor Oil Balancing .

1. Install the compressor (2).

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

2. Install the compressor mounting bolts.

Tighten
Tighten the bolts to 50 N·m (37 lb ft).

3. Install the new compressor sealing washers. Refer to Sealing Washer Replacement .



4. Connect the refrigerant hoses (2) to the compressor (3).
5. Install the compressor hose bolt.

Tighten
Tighten the bolt to 35 N·m (26 lb ft).

6. Connect the compressor clutch electrical connector.
7. Connect the high pressure switch electrical connector.
8. Install the drive belt. Refer to Drive Belt Replacement in Engine Mechanical-8.1L.
9. Install the air cleaner layer. Refer to Air Cleaner Replacement in Engine Controls-8.1L.
10. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
11. Leak test the fittings of the component using the J 39400-A .
12. Install the right wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.

Air Conditioning Compressor Replacement LG4

Tools Required

J 39400-A Halogen Leak Detector

1. Remove the right wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.
2. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging .
3. Remove the air cleaner layer. Refer to Air Cleaner Replacement in Engine Controls-7.8L.
4. Remove the drive belt. Refer to Drive Belt Replacement in Engine Mechanical-7.8L.
5. Disconnect the compressor clutch electrical connector.
6. Disconnect the high pressure switch connector.



7. Remove the compressor hose bolt (2) from the compressor (3).

Important: When removing the sealing washers, prevent dirt and foreign material from getting onto the following sealing surfaces:

•	The washers

•	The hose fitting

•	The compressor ports

Use a lint-free cloth in order to clean all of the sealing surfaces.
8. Remove the compressor sealing washers.

Discard the compressor sealing washers.

9. Remove the refrigerant hoses from the compressor.



10. Remove the compressor mounting bolts (1).
11. Remove the compressor (2).
12. If replacing the compressor, balance the refrigerant oil. Refer to Compressor Oil Balancing .

1. Install the compressor (2).

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.




2. Install the compressor mounting bolts (1).

Tighten
Tighten the bolts to 50 N·m (37 lb ft).

3. Install the new compressor sealing washers. Refer to Sealing Washer Replacement .



4. Install the refrigerant hose fitting (1) on the compressor (3).
5. Install the compressor hose bolt.

Tighten
Tighten the bolt to 35 N·m (26 lb ft).

6. Connect the compressor clutch electrical connector.
7. Connect the high pressure switch connector.
8. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
9. Install the drive belt. Refer to Drive Belt Replacement in Engine Mechanical-7.8L.
10. Install the air cleaner layer. Refer to Air Cleaner Replacement in Engine Controls-7.8L.
11. Leak test the fittings of the component using the J 39400-A .
12. Install the right wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.

Air Conditioning Compressor Replacement LLY

Tools Required

J 39400-A Halogen Leak Detector

1. Remove the left wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.
2. Remove the air cleaner. Refer to Air Cleaner Replacement in Engine Controls - 7.2L (Caterpillar).
3. Remove the drive belt. Refer to Drive Belt Replacement in Engine Mechanical - 6.6L (LLY).
4. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging .
5. Disconnect the compressor clutch electrical connector.
6. Disconnect the high pressure switch connector.




Important: When removing the sealing washers, prevent dirt and foreign material from getting on the following sealing surfaces:

•	The washers

•	The hose fitting

•	The compressor sealing surface

Use a lint-free cloth in order to clean all of the sealing surfaces.
7. Remove the compressor hose bolt (1).
8. Disconnect the compressor hose.
9. Remove the compressor sealing washers and discard.
10. Remove the refrigerant hoses (2) from the compressor (3).



11. Remove the compressor mounting bolts (1).
12. Remove the compressor (3) from the drive belt tensioner bracket (2).
13. If replacing the compressor, balance the refrigerant oil. Refer to Compressor Oil Balancing .

1. Install the compressor (3).

Notice: Refer to Fastener Notice in the Preface section.

2. Install the compressor mounting bolts.

Tighten
Tighten the bolts to 50 N·m (37 lb ft).

3. Install the new compressor sealing washers. Refer to Sealing Washer Replacement .



4. Connect the refrigerant hoses (2) to the compressor (3).
5. Install the compressor hose bolt.

Tighten
Tighten the bolt to 35 N·m (26 lb ft).

6. Connect the compressor clutch electrical connector.
7. Connect the high pressure switch connector.
8. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
9. Install the drive belt. Refer to Drive Belt Replacement in Engine Mechanical - 6.6L (LLY).
10. Install the air cleaner. Refer to Air Cleaner Replacement in Engine Controls - 7.2L (Caterpillar).
11. Leak test the fittings of the component using the J 39400-A .
12. Install the left wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Front End.