However, if you're determined to attempt this yourself, here's a general outline. This is a simplified overview and doesn't cover every detail. Consult a repair manual specific to your 1999 Chevrolet Express van for detailed instructions, diagrams, and torque specifications.
1. Safety First:
* Disconnect the battery: This prevents accidental short circuits.
* Wear safety glasses and gloves: Protecting yourself from sharp edges, refrigerant, and other hazards is crucial.
* Recover the refrigerant: Before disconnecting anything, have a qualified technician or use a recovery machine to evacuate the refrigerant from the system. Releasing refrigerant into the atmosphere is illegal and harmful to the environment.
2. Preparation:
* Gather tools: You'll need various wrenches, sockets, a compressor clutch tool, possibly a serpentine belt tensioner tool, a vacuum pump, refrigerant charging equipment, and possibly a manifold gauge set.
* Consult your repair manual: This is essential for identifying the correct parts, torque specifications, and procedures.
* Obtain the correct replacement compressor: Make sure you get the exact replacement for your van's model and year to ensure proper fit and function.
3. Removal of the Old Compressor:
* Disconnect the electrical connector: Usually located on the compressor itself.
* Disconnect the refrigerant lines: Use a flare nut wrench and carefully disconnect the high-pressure and low-pressure lines. Immediately cap them to prevent contamination.
* Remove the compressor mounting bolts: These are usually located on the compressor's mounting bracket.
* Remove the serpentine belt: This may require using a belt tensioner tool.
* Remove the compressor: Once all connections are disconnected and bolts removed, carefully remove the old compressor.
4. Installation of the New Compressor:
* Install the new compressor: Carefully align the new compressor with its mounting bracket and secure it with the mounting bolts. Tighten to the manufacturer's specifications.
* Reconnect the serpentine belt: Ensure proper alignment and tension.
* Reconnect the refrigerant lines: Carefully connect the high-pressure and low-pressure lines, ensuring proper seating and tightening to specifications. Check for leaks using leak detection solution.
* Reconnect the electrical connector: Make sure the connection is secure.
5. System Evacuation and Charging:
* Evacuate the system: Use a vacuum pump to remove any air and moisture from the AC system. This is critical to prevent damage to the compressor.
* Charge the system: Use a refrigerant charging machine and follow the instructions in your repair manual to charge the system with the correct amount and type of refrigerant. This usually involves using a manifold gauge set to monitor pressure.
6. Testing:
* Turn on the AC: After charging, test the system thoroughly to ensure proper cooling and check for leaks.
Disclaimer: This is a general overview, and the specific steps may vary depending on your van's model and configuration. Always consult a repair manual for your specific vehicle and prioritize safety. If you are not comfortable with any of these steps, seek professional assistance from a qualified mechanic. Improper AC repair can lead to significant damage and expense.
